Add cst command.

# Conflicts:
#	src/name_analysis/gather.rs

Cargo.lock

@@ -169,6 +169,17 @@ dependencies = [
  "typenum",
 ]
 
+[[package]]
+name = "cst-test-generator"
+version = "0.1.0"
+dependencies = [
+ "convert_case",
+ "prettyplease",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "deimos"
 version = "0.1.0"
@@ -176,6 +187,7 @@ dependencies = [
  "ast-generator",
  "clap",
  "codespan-reporting",
+ "cst-test-generator",
  "indoc",
  "log",
  "pest",
@@ -271,28 +283,21 @@ version = "2.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "78ca9ab1a0babb1e7d5695e3530886289c18cf2f87ec19a575a0abdce112e3a3"
 
-[[package]]
-name = "once_cell"
-version = "1.20.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1261fe7e33c73b354eab43b1273a57c8f967d0391e80353e51f764ac02cf6775"
-
 [[package]]
 name = "pest"
-version = "2.8.0"
+version = "2.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "198db74531d58c70a361c42201efde7e2591e976d518caf7662a47dc5720e7b6"
+checksum = "cbcfd20a6d4eeba40179f05735784ad32bdaef05ce8e8af05f180d45bb3e7e22"
 dependencies = [
  "memchr",
- "thiserror",
  "ucd-trie",
 ]
 
 [[package]]
 name = "pest_derive"
-version = "2.8.0"
+version = "2.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d725d9cfd79e87dccc9341a2ef39d1b6f6353d68c4b33c177febbe1a402c97c5"
+checksum = "51f72981ade67b1ca6adc26ec221be9f463f2b5839c7508998daa17c23d94d7f"
 dependencies = [
  "pest",
  "pest_generator",
@@ -300,9 +305,9 @@ dependencies = [
 
 [[package]]
 name = "pest_generator"
-version = "2.8.0"
+version = "2.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "db7d01726be8ab66ab32f9df467ae8b1148906685bbe75c82d1e65d7f5b3f841"
+checksum = "dee9efd8cdb50d719a80088b76f81aec7c41ed6d522ee750178f83883d271625"
 dependencies = [
  "pest",
  "pest_meta",
@@ -313,11 +318,10 @@ dependencies = [
 
 [[package]]
 name = "pest_meta"
-version = "2.8.0"
+version = "2.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f9f832470494906d1fca5329f8ab5791cc60beb230c74815dff541cbd2b5ca0"
+checksum = "bf1d70880e76bdc13ba52eafa6239ce793d85c8e43896507e43dd8984ff05b82"
 dependencies = [
- "once_cell",
  "pest",
  "sha2",
 ]
@@ -407,26 +411,6 @@ dependencies = [
  "winapi-util",
 ]
 
-[[package]]
-name = "thiserror"
-version = "2.0.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "567b8a2dae586314f7be2a752ec7474332959c6460e02bde30d702a66d488708"
-dependencies = [
- "thiserror-impl",
-]
-
-[[package]]
-name = "thiserror-impl"
-version = "2.0.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f7cf42b4507d8ea322120659672cf1b9dbb93f8f2d4ecfd6e51350ff5b17a1d"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
-
 [[package]]
 name = "typenum"
 version = "1.17.0"

Cargo.toml

@@ -12,16 +12,17 @@ name = "dmc"
 path = "src/bin/dmc/main.rs"
 
 [dependencies]
-pest = { version = "2.8.0" }
+pest = { version = "2.8.4" }
 clap = { version = "4.5.23", features = ["derive"] }
-pest_derive = { version = "2.8.0", features = ["grammar-extras"] }
+pest_derive = { version = "2.8.4", features = ["grammar-extras"] }
 codespan-reporting = "0.12.0"
 log = "0.4.27"
 indoc = "2.0.6"
 
 [build-dependencies]
 ast-generator = { path = "ast-generator" }
+cst-test-generator = { path = "cst-test-generator" }
 
 [workspace]
 resolver = "3"
-members = ["ast-generator"]
+members = ["ast-generator", "cst-test-generator"]

ast-generator/src/ast_node/enum_ast_node.rs

@@ -0,0 +1,87 @@
+use crate::spec::tree_enum_spec::{EnumRuleChildKind, TreeEnumBuildSpec};
+use convert_case::{Case, Casing};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_enum_ast_node_impl(enum_spec: &TreeEnumBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", enum_spec.build());
+    let match_arms = enum_spec
+        .rules()
+        .map(|rule| {
+            let rule_ident = format_ident!("{}", rule.rule());
+            match rule.child() {
+                Some(child) => match child.kind() {
+                    EnumRuleChildKind::Node(node_child) => {
+                        let child_ident =
+                            format_ident!("{}", node_child.node_kind().to_case(Case::Snake));
+                        quote! {
+                            #type_ident::#rule_ident(#child_ident) => vec![
+                                #child_ident
+                            ]
+                        }
+                    }
+                    _ => quote! {
+                        #type_ident::#rule_ident(_) => vec![]
+                    },
+                },
+                None => {
+                    quote! {
+                        #type_ident::#rule_ident => vec![]
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let mut_match_arms = enum_spec
+        .rules()
+        .map(|rule| {
+            let rule_ident = format_ident!("{}", rule.rule());
+            match rule.child() {
+                Some(child) => match child.kind() {
+                    EnumRuleChildKind::Node(node_child) => {
+                        let child_ident =
+                            format_ident!("{}", node_child.node_kind().to_case(Case::Snake));
+                        quote! {
+                            #type_ident::#rule_ident(#child_ident) => {
+                                f(#child_ident as &'a mut dyn AstNode<'a>)
+                            }
+                        }
+                    }
+                    _ => quote! {
+                        #type_ident::#rule_ident(_) => {}
+                    },
+                },
+                None => {
+                    quote! {
+                        #type_ident::#rule_ident => {}
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        impl<'a> AstNode<'a> for #type_ident {
+            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>> {
+                match self {
+                    #(#match_arms,)*
+                }
+            }
+
+            fn for_each_child_mut(&'a mut self, mut f: &mut dyn FnMut(&'a mut dyn AstNode<'a>)) {
+                match self {
+                    #(#mut_match_arms,)*
+                }
+            }
+
+            fn as_node_ref(&'a self) -> AstNodeRef<'a> {
+                AstNodeRef::#type_ident(&self)
+            }
+
+            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a> {
+                AstNodeRefMut::#type_ident(self)
+            }
+        }
+    }
+}

ast-generator/src/ast_node/leaf_enum_ast_node.rs

@@ -0,0 +1,24 @@
+use crate::spec::leaf_enum_spec::LeafEnumBuildSpec;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_leaf_enum_ast_node_impl(spec: &LeafEnumBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.build());
+    quote! {
+        impl<'a> AstNode<'a> for #type_ident {
+            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>> {
+                vec![]
+            }
+
+            fn for_each_child_mut(&'a mut self, mut f: &mut dyn FnMut(&'a mut dyn AstNode<'a>)) {}
+
+            fn as_node_ref(&'a self) -> AstNodeRef<'a> {
+                AstNodeRef::#type_ident(&self)
+            }
+
+            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a> {
+                AstNodeRefMut::#type_ident(self)
+            }
+        }
+    }
+}

ast-generator/src/ast_node/leaf_struct_ast_node.rs

@@ -0,0 +1,24 @@
+use crate::spec::leaf_struct_spec::LeafStructBuildSpec;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_leaf_struct_ast_node_impl(spec: &LeafStructBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.build());
+    quote! {
+        impl<'a> AstNode<'a> for #type_ident {
+            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>> {
+                vec![]
+            }
+
+            fn for_each_child_mut(&'a mut self, mut f: &mut dyn FnMut(&'a mut dyn AstNode<'a>)) {}
+
+            fn as_node_ref(&'a self) -> AstNodeRef<'a> {
+                AstNodeRef::#type_ident(&self)
+            }
+
+            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a> {
+                AstNodeRefMut::#type_ident(self)
+            }
+        }
+    }
+}

ast-generator/src/ast_node/mod.rs

@@ -0,0 +1,96 @@
+mod enum_ast_node;
+mod leaf_enum_ast_node;
+mod leaf_struct_ast_node;
+mod polymorphic_enum_inner_build_ast_node;
+mod polymorphic_enum_loop_ast_node;
+mod polymorphic_type_ast_node;
+mod struct_ast_node;
+
+use crate::ast_node::enum_ast_node::make_enum_ast_node_impl;
+use crate::ast_node::leaf_enum_ast_node::make_leaf_enum_ast_node_impl;
+use crate::ast_node::leaf_struct_ast_node::make_leaf_struct_ast_node_impl;
+use crate::ast_node::polymorphic_enum_inner_build_ast_node::make_polymorphic_enum_inner_build_ast_node_impl;
+use crate::ast_node::polymorphic_enum_loop_ast_node::make_polymorphic_enum_loop_ast_node_impl;
+use crate::ast_node::polymorphic_type_ast_node::make_polymorphic_type_ast_node_impl;
+use crate::ast_node::struct_ast_node::make_struct_ast_node_impl;
+use crate::spec::BuildSpec;
+use proc_macro2::{Ident, TokenStream};
+use quote::{format_ident, quote};
+
+pub fn make_ast_node_impl(build_spec: &BuildSpec) -> Option<TokenStream> {
+    match build_spec {
+        BuildSpec::Enum(enum_spec) => Some(make_enum_ast_node_impl(enum_spec)),
+        BuildSpec::LeafEnum(leaf_enum) => Some(make_leaf_enum_ast_node_impl(leaf_enum)),
+        BuildSpec::Struct(struct_spec) => Some(make_struct_ast_node_impl(struct_spec)),
+        BuildSpec::LeafStruct(leaf_struct) => Some(make_leaf_struct_ast_node_impl(leaf_struct)),
+        BuildSpec::Production(_) => None,
+        BuildSpec::NodeProduction(_) => None,
+        BuildSpec::PolymorphicType(polymorphic_type) => {
+            Some(make_polymorphic_type_ast_node_impl(polymorphic_type))
+        }
+        BuildSpec::PolymorphicEnumLoop(polymorphic_enum_loop) => Some(
+            make_polymorphic_enum_loop_ast_node_impl(polymorphic_enum_loop),
+        ),
+        BuildSpec::PolymorphicPassThrough(_) => None,
+        BuildSpec::PolymorphicEnumInnerBuild(polymorphic_enum_inner_build) => Some(
+            make_polymorphic_enum_inner_build_ast_node_impl(polymorphic_enum_inner_build),
+        ),
+        BuildSpec::PolymorphicLeafEnum(_) => None,
+        BuildSpec::PolymorphicTreeEnum(_) => None,
+    }
+}
+
+fn make_type_ident(build_spec: &BuildSpec) -> Option<Ident> {
+    match build_spec {
+        BuildSpec::Struct(struct_spec) => Some(format_ident!("{}", struct_spec.build())),
+        BuildSpec::LeafStruct(leaf_struct) => Some(format_ident!("{}", leaf_struct.build())),
+        BuildSpec::Enum(enum_spec) => Some(format_ident!("{}", enum_spec.build())),
+        BuildSpec::LeafEnum(leaf_enum) => Some(format_ident!("{}", leaf_enum.build())),
+        BuildSpec::PolymorphicType(polymorphic_type) => {
+            Some(format_ident!("{}", polymorphic_type.name()))
+        }
+        BuildSpec::PolymorphicEnumLoop(polymorphic_enum_loop) => {
+            Some(format_ident!("{}", polymorphic_enum_loop.name()))
+        }
+        BuildSpec::PolymorphicPassThrough(_) => None,
+        BuildSpec::Production(_) => None,
+        BuildSpec::NodeProduction(_) => None,
+        BuildSpec::PolymorphicEnumInnerBuild(polymorphic_enum_inner_build) => {
+            Some(format_ident!("{}", polymorphic_enum_inner_build.name()))
+        }
+        BuildSpec::PolymorphicLeafEnum(_) => None,
+        BuildSpec::PolymorphicTreeEnum(_) => None,
+    }
+}
+
+pub fn make_ast_enum_member(build_spec: &BuildSpec) -> Option<TokenStream> {
+    make_type_ident(build_spec).map(|type_ident| {
+        quote! {
+            #type_ident(&'a #type_ident)
+        }
+    })
+}
+
+pub fn make_ast_enum_mut_member(build_spec: &BuildSpec) -> Option<TokenStream> {
+    make_type_ident(build_spec).map(|type_ident| {
+        quote! {
+            #type_ident(&'a mut #type_ident)
+        }
+    })
+}
+
+pub fn make_ast_node_ref_unwrapper(build_spec: &BuildSpec) -> Option<TokenStream> {
+    make_type_ident(build_spec).map(|type_ident| {
+        quote! {
+            AstNodeRef::#type_ident(inner) => *inner
+        }
+    })
+}
+
+pub fn make_ast_node_ref_mut_unwrapper(build_spec: &BuildSpec) -> Option<TokenStream> {
+    make_type_ident(build_spec).map(|type_ident| {
+        quote! {
+            AstNodeRefMut::#type_ident(inner) => *inner
+        }
+    })
+}

ast-generator/src/ast_node/polymorphic_enum_inner_build_ast_node.rs

@@ -0,0 +1,76 @@
+use convert_case::{Case, Casing};
+use crate::spec::polymorphic_enum_inner_build::{PolymorphicEnumInnerBuild, PolymorphicEnumInnerBuildMemberKind};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_enum_inner_build_ast_node_impl(
+    spec: &PolymorphicEnumInnerBuild,
+) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.name());
+
+    let match_arms = spec.members()
+        .map(|member| {
+            let member_ident = format_ident!("{}", member.name());
+            match member.kind() {
+                PolymorphicEnumInnerBuildMemberKind::Leaf => {
+                    quote! {
+                        #type_ident::#member_ident => vec![]
+                    }
+                }
+                PolymorphicEnumInnerBuildMemberKind::Struct => {
+                    let child_ident = format_ident!("{}", member.name().to_case(Case::Snake));
+                    quote! {
+                        #type_ident::#member_ident(#child_ident) => vec![
+                            #child_ident
+                        ]
+                    }
+                }
+            }    
+        })
+        .collect::<Vec<_>>();
+    
+    let mut_match_arms = spec.members()
+        .map(|member| {
+            let member_ident = format_ident!("{}", member.name());
+            match member.kind() {
+                PolymorphicEnumInnerBuildMemberKind::Leaf => {
+                    quote! {
+                        #type_ident::#member_ident => {}
+                    }
+                }
+                PolymorphicEnumInnerBuildMemberKind::Struct => {
+                    let child_ident = format_ident!("{}", member.name().to_case(Case::Snake));
+                    quote! {
+                        #type_ident::#member_ident(#child_ident) => {
+                            f(#child_ident as &'a mut dyn AstNode<'a>)
+                        }
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+    
+    quote! {
+        impl<'a> AstNode<'a> for #type_ident {
+            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>> {
+                match self {
+                    #(#match_arms,)*
+                }
+            }
+
+            fn for_each_child_mut(&'a mut self, mut f: &mut dyn FnMut(&'a mut dyn AstNode<'a>)) {
+                match self {
+                    #(#mut_match_arms,)*
+                }
+            }
+
+            fn as_node_ref(&'a self) -> AstNodeRef<'a> {
+                AstNodeRef::#type_ident(&self)
+            }
+
+            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a> {
+                AstNodeRefMut::#type_ident(self)
+            }
+        }
+    }
+}

ast-generator/src/ast_node/polymorphic_enum_loop_ast_node.rs

@@ -0,0 +1,62 @@
+use crate::spec::polymorphic_enum_loop_spec::{
+    PolymorphicEnumLoopBuildSpec, PolymorphicEnumLoopRule, PolymorphicEnumLoopRuleBuildChild,
+};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_enum_loop_ast_node_impl(
+    spec: &PolymorphicEnumLoopBuildSpec,
+) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.name());
+    let build_rule = spec
+        .rules()
+        .filter_map(|rule| match rule {
+            PolymorphicEnumLoopRule::PassThrough(_) => None,
+            PolymorphicEnumLoopRule::Build(build_rule) => Some(build_rule),
+        })
+        .next()
+        .unwrap();
+    let child_adders = build_rule
+        .children()
+        .map(|child| {
+            let child_ident = match child {
+                PolymorphicEnumLoopRuleBuildChild::UseCurrent(use_current) => {
+                    Some(format_ident!("{}", use_current.name()))
+                }
+                PolymorphicEnumLoopRuleBuildChild::OnEach(on_each) => {
+                    Some(format_ident!("{}", on_each.name()))
+                }
+                PolymorphicEnumLoopRuleBuildChild::Special(_) => None,
+            };
+            child_ident.map(|child_ident| {
+                quote! {
+                    children.push(self.#child_ident() as &dyn AstNode);
+                }
+            })
+        })
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    quote! {
+        impl<'a> AstNode<'a> for #type_ident {
+            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>> {
+                let mut children = vec![];
+                #(#child_adders;)*
+                children
+            }
+
+            fn for_each_child_mut(&'a mut self, mut f: &mut dyn FnMut(&'a mut dyn AstNode<'a>)) {
+                todo!()
+            }
+
+            fn as_node_ref(&'a self) -> AstNodeRef<'a> {
+                AstNodeRef::#type_ident(&self)
+            }
+
+            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a> {
+                AstNodeRefMut::#type_ident(self)
+            }
+        }
+    }
+}

ast-generator/src/ast_node/polymorphic_type_ast_node.rs

@@ -0,0 +1,55 @@
+use crate::spec::polymorphic_type_spec::PolymorphicTypeBuildSpec;
+use convert_case::{Case, Casing};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_type_ast_node_impl(spec: &PolymorphicTypeBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.name());
+    let match_arms = spec
+        .variants()
+        .map(|variant| {
+            let variant_ident = format_ident!("{}", variant.name());
+            let child_ident = format_ident!("{}", variant.inner_kind().to_case(Case::Snake));
+            quote! {
+                #type_ident::#variant_ident(#child_ident) => vec![#child_ident]
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let match_arms_mut = spec
+        .variants()
+        .map(|variant| {
+            let variant_ident = format_ident!("{}", variant.name());
+            let child_ident = format_ident!("{}", variant.inner_kind().to_case(Case::Snake));
+            quote! {
+                #type_ident::#variant_ident(#child_ident) => {
+                    f(#child_ident as &'a mut dyn AstNode)
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        impl<'a> AstNode<'a> for #type_ident {
+            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>> {
+                match self {
+                    #(#match_arms,)*
+                }
+            }
+
+            fn for_each_child_mut(&'a mut self, mut f: &mut dyn FnMut(&'a mut dyn AstNode<'a>)) {
+                match self {
+                    #(#match_arms_mut,)*
+                }
+            }
+
+            fn as_node_ref(&'a self) -> AstNodeRef<'a> {
+                AstNodeRef::#type_ident(&self)
+            }
+
+            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a> {
+                AstNodeRefMut::#type_ident(self)
+            }
+        }
+    }
+}

ast-generator/src/ast_node/struct_ast_node.rs

@@ -0,0 +1,86 @@
+use crate::spec::struct_spec::{MemberChildBuild, StructChild, StructSpec, VecChildBuild};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+fn make_child_adders(spec: &StructSpec, is_mut: bool) -> Vec<TokenStream> {
+    let as_clause = if is_mut {
+        quote! { as &mut dyn AstNode }
+    } else {
+        quote! { as &dyn AstNode }
+    };
+
+    spec.children()
+        .map(|child| match child {
+            StructChild::SkipChild(_) => None,
+            StructChild::VecChild(vec_child) => match vec_child.build() {
+                VecChildBuild::String(_) => None,
+                VecChildBuild::Node(_) => {
+                    let child_ident = if is_mut {
+                        format_ident!("{}_mut", vec_child.name())
+                    } else {
+                        format_ident!("{}", vec_child.name())
+                    };
+                    let children_stream = quote! {
+                        for child in self.#child_ident() {
+                            children.push(child #as_clause);
+                        }
+                    };
+                    Some(children_stream)
+                }
+            },
+            StructChild::MemberChild(member_child) => match member_child.build() {
+                MemberChildBuild::Node(_) => {
+                    let child_ident = if is_mut {
+                        format_ident!("{}_mut", member_child.name())
+                    } else {
+                        format_ident!("{}", member_child.name())
+                    };
+
+                    if member_child.optional() {
+                        Some(quote! {
+                            if let Some(#child_ident) = self.#child_ident() {
+                                children.push(#child_ident #as_clause);
+                            }
+                        })
+                    } else {
+                        Some(quote! {
+                            children.push(self.#child_ident() #as_clause)
+                        })
+                    }
+                }
+                MemberChildBuild::Boolean(_) => None,
+            },
+            StructChild::Special(_) => None,
+        })
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>()
+}
+
+pub fn make_struct_ast_node_impl(spec: &StructSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.build());
+    let child_adders = make_child_adders(spec, false);
+    let child_adders_mut = make_child_adders(spec, true);
+
+    quote! {
+        impl<'a> AstNode<'a> for #type_ident {
+            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>> {
+                let mut children = vec![];
+                #(#child_adders;)*
+                children
+            }
+
+            fn for_each_child_mut(&'a mut self, mut f: &mut dyn FnMut(&'a mut dyn AstNode<'a>)) {
+                todo!()
+            }
+
+            fn as_node_ref(&'a self) -> AstNodeRef<'a> {
+                AstNodeRef::#type_ident(&self)
+            }
+
+            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a> {
+                AstNodeRefMut::#type_ident(self)
+            }
+        }
+    }
+}

ast-generator/src/build_fn/leaf_enum_build_fn.rs

@@ -0,0 +1,30 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::leaf_enum_spec::LeafEnumBuildSpec;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_leaf_enum_build_fn(leaf_enum_build_spec: &LeafEnumBuildSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(leaf_enum_build_spec.build()));
+    let pair_ident = format_ident!("{}", make_build_pair(leaf_enum_build_spec.build()));
+    let return_type_ident = format_ident!("{}", leaf_enum_build_spec.build());
+
+    let rule_branches = leaf_enum_build_spec
+        .rules()
+        .map(|leaf_enum_rule| {
+            let rule_ident = format_ident!("{}", leaf_enum_rule);
+            quote! {
+                Rule::#rule_ident => #return_type_ident::#rule_ident
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            let inner_pair = #pair_ident.into_inner().next().unwrap();
+            match inner_pair.as_rule() {
+                #(#rule_branches,)*
+                _ => unreachable!()
+            }
+        }
+    }
+}

ast-generator/src/build_fn/leaf_struct_build_fn.rs

@@ -0,0 +1,54 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::leaf_struct_spec::{LeafStructBuildSpec, LeafStructMemberKind};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_leaf_struct_build_fn(build_spec: &LeafStructBuildSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(build_spec.build()));
+    let pair_ident = format_ident!("{}", make_build_pair(build_spec.build()));
+    let return_type_ident = format_ident!("{}", build_spec.build());
+
+    let child_builders = build_spec
+        .members()
+        .map(|member| {
+            let child_ident = format_ident!("{}", member.name());
+            match member.kind() {
+                LeafStructMemberKind::String => {
+                    quote! {
+                        let #child_ident = #pair_ident.as_str()
+                    }
+                }
+                LeafStructMemberKind::FileId => {
+                    quote! {
+                        let #child_ident = file_id
+                    }
+                }
+                LeafStructMemberKind::Range => {
+                    quote! {
+                        let #child_ident = {
+                            let as_span = #pair_ident.as_span();
+                            Range {
+                                start: as_span.start(),
+                                end: as_span.end()
+                            }
+                        }
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let child_args = build_spec
+        .members()
+        .map(|member| format_ident!("{}", member.name()))
+        .collect::<Vec<_>>();
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            #(#child_builders;)*
+            #return_type_ident::new(
+                #(#child_args,)*
+            )
+        }
+    }
+}

ast-generator/src/build_fn/mod.rs

@@ -0,0 +1,58 @@
+use crate::spec::BuildSpec;
+use leaf_enum_build_fn::make_leaf_enum_build_fn;
+use leaf_struct_build_fn::make_leaf_struct_build_fn;
+use node_production_build_fn::make_node_production_build_fn;
+use polymorphic_enum_inner_build_build_fn::make_polymorphic_enum_inner_build_build_fn;
+use polymorphic_enum_loop_build_fn::make_polymorphic_enum_loop_build_fn;
+use polymorphic_leaf_enum_build_fn::make_polymorphic_leaf_enum_build_fn;
+use polymorphic_pass_through_build_fn::make_polymorphic_pass_through_build_fn;
+use polymorphic_tree_enum_build_fn::make_polymorphic_tree_enum_build_fn;
+use polymorphic_type_build_fn::make_polymorphic_type_build_fn;
+use proc_macro2::TokenStream;
+use production_build_fn::make_production_build_fn;
+use struct_build_fn::make_struct_build_fn;
+use tree_enum_build_fn::make_enum_build_fn;
+
+mod leaf_enum_build_fn;
+mod leaf_struct_build_fn;
+mod node_production_build_fn;
+mod polymorphic_enum_inner_build_build_fn;
+mod polymorphic_enum_loop_build_fn;
+mod polymorphic_leaf_enum_build_fn;
+mod polymorphic_pass_through_build_fn;
+mod polymorphic_tree_enum_build_fn;
+mod polymorphic_type_build_fn;
+mod production_build_fn;
+mod struct_build_fn;
+mod tree_enum_build_fn;
+
+pub fn make_build_fn(build_spec: &BuildSpec) -> TokenStream {
+    match build_spec {
+        BuildSpec::Struct(struct_spec) => make_struct_build_fn(struct_spec),
+        BuildSpec::LeafStruct(leaf_struct_spec) => make_leaf_struct_build_fn(leaf_struct_spec),
+        BuildSpec::Enum(enum_spec) => make_enum_build_fn(enum_spec),
+        BuildSpec::LeafEnum(leaf_enum_spec) => make_leaf_enum_build_fn(leaf_enum_spec),
+        BuildSpec::Production(production_spec) => make_production_build_fn(production_spec),
+        BuildSpec::NodeProduction(node_production_spec) => {
+            make_node_production_build_fn(node_production_spec)
+        }
+        BuildSpec::PolymorphicType(polymorphic_type_spec) => {
+            make_polymorphic_type_build_fn(polymorphic_type_spec)
+        }
+        BuildSpec::PolymorphicEnumLoop(polymorphic_enum_loop_spec) => {
+            make_polymorphic_enum_loop_build_fn(polymorphic_enum_loop_spec)
+        }
+        BuildSpec::PolymorphicPassThrough(polymorphic_pass_through_spec) => {
+            make_polymorphic_pass_through_build_fn(polymorphic_pass_through_spec)
+        }
+        BuildSpec::PolymorphicEnumInnerBuild(polymorphic_enum_inner_build_spec) => {
+            make_polymorphic_enum_inner_build_build_fn(polymorphic_enum_inner_build_spec)
+        }
+        BuildSpec::PolymorphicLeafEnum(polymorphic_leaf_enum_spec) => {
+            make_polymorphic_leaf_enum_build_fn(polymorphic_leaf_enum_spec)
+        }
+        BuildSpec::PolymorphicTreeEnum(polymorphic_tree_enum_spec) => {
+            make_polymorphic_tree_enum_build_fn(polymorphic_tree_enum_spec)
+        }
+    }
+}

ast-generator/src/build_fn/node_production_build_fn.rs

@@ -0,0 +1,18 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::node_production_spec::NodeProductionBuildSpec;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_node_production_build_fn(spec: &NodeProductionBuildSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(spec.name()));
+    let pair_ident = format_ident!("{}", make_build_pair(spec.name()));
+    let return_type_ident = format_ident!("{}", spec.kind());
+    let inner_build_fn_ident = format_ident!("{}", spec.with());
+    
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            let inner_pair = #pair_ident.into_inner().next().unwrap();
+            #inner_build_fn_ident(file_id, inner_pair)
+        }
+    }
+}

ast-generator/src/build_fn/polymorphic_enum_inner_build_build_fn.rs

@@ -0,0 +1,30 @@
+use crate::spec::polymorphic_enum_inner_build::PolymorphicEnumInnerBuild;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+
+pub fn make_polymorphic_enum_inner_build_build_fn(spec: &PolymorphicEnumInnerBuild) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(spec.name()));
+    let pair_ident = format_ident!("{}", make_build_pair(spec.name()));
+    let return_type_ident = format_ident!("{}", spec.name());
+    
+    let rule_branches = spec.rules()
+        .map(|rule| {
+            let rule_ident = format_ident!("{}", rule.name());
+            let rule_build_fn_ident = format_ident!("{}", rule.with());
+            quote! {
+                Rule::#rule_ident => #rule_build_fn_ident(file_id, inner_pair)
+            }
+        })
+        .collect::<Vec<_>>();
+    
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            let inner_pair = #pair_ident.into_inner().next().unwrap();
+            match inner_pair.as_rule() {
+                #(#rule_branches,)*
+                _ => unreachable!()
+            }
+        }
+    }
+}

ast-generator/src/build_fn/polymorphic_enum_loop_build_fn.rs

@@ -0,0 +1,135 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::polymorphic_enum_loop_spec::{
+    PolymorphicEnumLoopBuildSpec, PolymorphicEnumLoopRule, PolymorphicEnumLoopRuleBuild,
+    PolymorphicEnumLoopRuleBuildChild, PolymorphicEnumLoopRuleChildOnEach,
+    PolymorphicEnumLoopRulePassThrough,
+};
+use crate::spec::SpecialChildKind;
+use proc_macro2::{Ident, TokenStream};
+use quote::{format_ident, quote};
+
+fn make_pass_through(pass_through: &PolymorphicEnumLoopRulePassThrough) -> TokenStream {
+    let rule_ident = format_ident!("{}", pass_through.name());
+    let inner_build_fn_ident = format_ident!("{}", pass_through.with());
+    quote! {
+        Rule::#rule_ident => {
+            result = Some(#inner_build_fn_ident(file_id, inner_pair))
+        }
+    }
+}
+
+fn make_on_each_child_build(child: &PolymorphicEnumLoopRuleChildOnEach) -> TokenStream {
+    let child_build_fn_ident = format_ident!("{}", make_build_fn_name(child.rule()));
+    quote! {
+        Box::new(#child_build_fn_ident(file_id, inner_pair))
+    }
+}
+
+fn make_build(
+    spec: &PolymorphicEnumLoopBuildSpec,
+    build: &PolymorphicEnumLoopRuleBuild,
+) -> TokenStream {
+    let rule_ident = format_ident!("{}", build.name());
+    let variant_type_ident = format_ident!("{}", spec.name());
+    let return_type_ident = format_ident!("{}", spec.kind());
+    let variant_ident = format_ident!("{}", build.variant());
+
+    let on_each_child = build
+        .children()
+        .find(|child| match child {
+            PolymorphicEnumLoopRuleBuildChild::OnEach(_) => true,
+            _ => false,
+        })
+        .map(|child| match child {
+            PolymorphicEnumLoopRuleBuildChild::OnEach(on_each) => on_each,
+            _ => unreachable!(),
+        })
+        .unwrap();
+
+    let build_on_each_child = make_on_each_child_build(on_each_child);
+
+    let child_args = build
+        .children()
+        .map(|child| match child {
+            PolymorphicEnumLoopRuleBuildChild::UseCurrent(_) => {
+                quote! { Box::new(result.unwrap()) }
+            }
+            PolymorphicEnumLoopRuleBuildChild::OnEach(_) => quote! { on_each_child },
+            PolymorphicEnumLoopRuleBuildChild::Special(special_child) => {
+                match special_child.kind() {
+                    SpecialChildKind::FileId => {
+                        quote! { file_id }
+                    }
+                    SpecialChildKind::Range => {
+                        quote! { Range { start: as_span.start(), end: as_span.end() } }
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        Rule::#rule_ident => {
+            let on_each_child = #build_on_each_child;
+            let built = #variant_type_ident::new(#(#child_args),*);
+            result = Some(#return_type_ident::#variant_ident(built))
+        }
+    }
+}
+
+fn make_match_arm(
+    spec: &PolymorphicEnumLoopBuildSpec,
+    rule: &PolymorphicEnumLoopRule,
+) -> TokenStream {
+    match rule {
+        PolymorphicEnumLoopRule::PassThrough(pass_through) => make_pass_through(pass_through),
+        PolymorphicEnumLoopRule::Build(build) => make_build(spec, build),
+    }
+}
+
+fn make_preamble(spec: &PolymorphicEnumLoopBuildSpec, pair_ident: &Ident) -> TokenStream {
+    if spec.rules().any(|rule| match rule {
+        PolymorphicEnumLoopRule::Build(build) => build.children().any(|child| match child {
+            PolymorphicEnumLoopRuleBuildChild::Special(_) => true,
+            _ => false,
+        }),
+        _ => false,
+    }) {
+        quote! { let as_span = #pair_ident.as_span(); }
+    } else {
+        quote! {}
+    }
+}
+
+pub fn make_polymorphic_enum_loop_build_fn(spec: &PolymorphicEnumLoopBuildSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(spec.name()));
+    let pair_ident = format_ident!("{}", make_build_pair(spec.name()));
+    let return_type_ident = format_ident!("{}", spec.kind());
+
+    let preamble = make_preamble(spec, &pair_ident);
+
+    let iter_expr = if spec.reverse() {
+        quote! { #pair_ident.into_inner().rev() }
+    } else {
+        quote! { #pair_ident.into_inner() }
+    };
+
+    let match_arms = spec
+        .rules()
+        .map(|rule| make_match_arm(spec, rule))
+        .collect::<Vec<_>>();
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            #preamble
+            let mut result: Option<#return_type_ident> = None;
+            for inner_pair in #iter_expr {
+                match inner_pair.as_rule() {
+                    #(#match_arms,)*
+                    _ => unreachable!("Unexpected parse rule: {:?} (inner pair: {:#?}", inner_pair.as_rule(), inner_pair),
+                }
+            }
+            result.unwrap()
+        }
+    }
+}

ast-generator/src/build_fn/polymorphic_leaf_enum_build_fn.rs

@@ -0,0 +1,29 @@
+use crate::spec::polymorphic_leaf_enum::PolymorphicLeafEnum;
+use convert_case::{Case, Casing};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_leaf_enum_build_fn(spec: &PolymorphicLeafEnum) -> TokenStream {
+    let build_fn_ident = format_ident!("build_{}", spec.name().to_case(Case::Snake));
+    let pair_ident = format_ident!("{}_pair", spec.name().to_case(Case::Snake));
+    let return_type_ident = format_ident!("{}", spec.kind());
+    
+    let child_matchers = spec.rules()
+        .map(|rule| {
+            let rule_ident = format_ident!("{}", rule);
+            quote! {
+                Rule::#rule_ident => #return_type_ident::#rule_ident
+            }    
+        })
+        .collect::<Vec<_>>();
+    
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            let inner_pair = #pair_ident.into_inner().next().unwrap();
+            match inner_pair.as_rule() {
+                #(#child_matchers,)*
+                _ => unreachable!()
+            }
+        }
+    }
+}

ast-generator/src/build_fn/polymorphic_pass_through_build_fn.rs

@@ -0,0 +1,51 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::polymorphic_pass_through_spec::{
+    PolymorphicPassThroughBuildSpec, PolymorphicPassThroughVariant,
+};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_pass_through_build_fn(
+    spec: &PolymorphicPassThroughBuildSpec,
+) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(spec.name()));
+    let pair_ident = format_ident!("{}", make_build_pair(spec.name()));
+    let return_type_ident = format_ident!("{}", spec.build_kind());
+
+    let match_arms = spec
+        .variants()
+        .map(|variant| match variant {
+            PolymorphicPassThroughVariant::Inner { name, kind } => {
+                let rule_ident = format_ident!("{}", kind);
+                let variant_ident = format_ident!("{}", name);
+                let inner_build_fn_ident = format_ident!("{}", make_build_fn_name(kind));
+
+                quote! {
+                    Rule::#rule_ident => {
+                        #return_type_ident::#variant_ident(
+                            #inner_build_fn_ident(file_id, inner_pair)
+                        )
+                    }
+                }
+            }
+            PolymorphicPassThroughVariant::PassThrough { name, kind: _kind } => {
+                let rule_ident = format_ident!("{}", name);
+                let inner_build_fn_ident = format_ident!("{}", make_build_fn_name(name));
+
+                quote! {
+                    Rule::#rule_ident => #inner_build_fn_ident(file_id, inner_pair)
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            let inner_pair = #pair_ident.into_inner().next().unwrap();
+            match inner_pair.as_rule() {
+                #(#match_arms,)*
+                _ => unreachable!(),
+            }
+        }
+    }
+}

ast-generator/src/build_fn/polymorphic_tree_enum_build_fn.rs

@@ -0,0 +1,33 @@
+use crate::spec::polymorphic_tree_enum_spec::PolymorphicTreeEnumSpec;
+use convert_case::{Case, Casing};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_tree_enum_build_fn(spec: &PolymorphicTreeEnumSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("build_{}", spec.name().to_case(Case::Snake));
+    let pair_ident = format_ident!("{}_pair", spec.name().to_case(Case::Snake));
+    let return_type_ident = format_ident!("{}", spec.kind());
+
+    let rule_matchers = spec
+        .rules()
+        .map(|rule| {
+            let rule_ident = format_ident!("{}", rule);
+            let inner_build_fn_ident = format_ident!("build_{}", rule.to_case(Case::Snake));
+            quote! {
+                Rule::#rule_ident => #return_type_ident::#rule_ident(
+                    #inner_build_fn_ident(file_id, inner_pair)
+                )
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            let inner_pair = #pair_ident.into_inner().next().unwrap();
+            match inner_pair.as_rule() {
+                #(#rule_matchers,)*
+                _ => unreachable!(),
+            }
+        }
+    }
+}

ast-generator/src/build_fn/polymorphic_type_build_fn.rs

@@ -0,0 +1,18 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::polymorphic_type_spec::PolymorphicTypeBuildSpec;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_type_build_fn(build_spec: &PolymorphicTypeBuildSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(build_spec.name()));
+    let pair_ident = format_ident!("{}", make_build_pair(&build_spec.name()));
+    let return_type_ident = format_ident!("{}", build_spec.name());
+    let inner_build_fn_ident = format_ident!("{}", make_build_fn_name(build_spec.kind()));
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            let inner_pair = #pair_ident.into_inner().next().unwrap();
+            #inner_build_fn_ident(file_id, inner_pair)
+        }
+    }
+}

ast-generator/src/build_fn/production_build_fn.rs

@@ -0,0 +1,87 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::production_spec::{ProductionBuildSpec, ProductionKind, ProductionStringFrom};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_production_build_fn(production_build_spec: &ProductionBuildSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(production_build_spec.name()));
+    let return_type_ident = match production_build_spec.kind() {
+        ProductionKind::Int => format_ident!("i32"),
+        ProductionKind::Long => format_ident!("i64"),
+        ProductionKind::Double => format_ident!("f64"),
+        ProductionKind::String(_) => format_ident!("String"),
+        ProductionKind::Boolean(_) => format_ident!("bool"),
+    };
+    let pair_ident = format_ident!("{}", make_build_pair(production_build_spec.name()));
+
+    let pair_mapper = match production_build_spec.kind() {
+        ProductionKind::Int => quote! {
+            let number_base_pair = #pair_ident.into_inner()
+                .next()
+                .unwrap();
+            let inner_number_base_pair = number_base_pair.into_inner()
+                .next()
+                .unwrap();
+            match inner_number_base_pair.as_rule() {
+                Rule::BinaryBase => {
+                    todo!()
+                }
+                Rule::HexadecimalBase => {
+                    todo!()
+                }
+                Rule::DecimalBase => {
+                    inner_number_base_pair.as_str().parse::<i32>().unwrap()
+                }
+                _ => panic!()
+            }
+        },
+        ProductionKind::Long => quote! {
+            let number_base_pair = #pair_ident.into_inner()
+                .next()
+                .unwrap();
+            let inner_number_base_pair = number_base_pair.into_inner()
+                .next()
+                .unwrap();
+            match inner_number_base_pair.as_rule() {
+                Rule::BinaryBase => {
+                    todo!()
+                }
+                Rule::HexadecimalBase => {
+                    todo!()
+                }
+                Rule::DecimalBase => {
+                    inner_number_base_pair.as_str().parse::<i64>().unwrap()
+                }
+                _ => panic!()
+            }
+        },
+        ProductionKind::Double => quote! {
+            #pair_ident.as_str().parse::<f64>().unwrap()
+        },
+        ProductionKind::String(from) => match from {
+            ProductionStringFrom::StringInner => {
+                quote! {
+                    #pair_ident.into_inner()
+                        .next()
+                        .unwrap()
+                        .as_str()
+                        .to_string()
+                }
+            }
+            ProductionStringFrom::WholePair => {
+                quote! {
+                    #pair_ident.as_str().to_string()
+                }
+            }
+        },
+        ProductionKind::Boolean(_) => quote! {
+            #pair_ident.as_str().parse::<bool>().unwrap()
+        },
+    };
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            #pair_mapper
+        }
+    }
+}

ast-generator/src/build_fn/struct_build_fn.rs

@@ -0,0 +1,273 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::struct_spec::{
+    MemberChildBuild, NodeMemberBuild, StructChild, StructSpec, VecChild, VecChildBuild,
+};
+use crate::spec::{SpecialChild, SpecialChildKind};
+use proc_macro2::{Ident, TokenStream};
+use quote::{format_ident, quote};
+
+fn make_preamble(spec: &StructSpec, pair_ident: &Ident) -> TokenStream {
+    if spec.children().any(StructChild::is_special) {
+        quote! {
+            let as_span = #pair_ident.as_span();
+        }
+    } else {
+        quote! {}
+    }
+}
+
+fn make_special_children(spec: &StructSpec) -> Vec<TokenStream> {
+    spec.children()
+        .map(StructChild::unwrap_special)
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .map(|special_child| {
+            let child_ident = format_ident!("{}", special_child.name());
+            match special_child.kind() {
+                SpecialChildKind::FileId => {
+                    quote! {
+                        let #child_ident = file_id
+                    }
+                }
+                SpecialChildKind::Range => {
+                    quote! {
+                        let #child_ident = Range {
+                            start: as_span.start(),
+                            end: as_span.end()
+                        }
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>()
+}
+
+fn make_vec_child_holder(vec_child: &VecChild) -> TokenStream {
+    let child_ident = format_ident!("{}", vec_child.name());
+    match vec_child.build() {
+        VecChildBuild::String(_) => {
+            quote! {
+                let mut #child_ident: Vec<String> = vec![]
+            }
+        }
+        VecChildBuild::Node(node_build) => {
+            let child_type_ident = format_ident!("{}", node_build.kind());
+            quote! {
+                let mut #child_ident: Vec<Box<#child_type_ident>> = vec![]
+            }
+        }
+    }
+}
+
+fn make_node_child_holder(name: &str, node_child: &NodeMemberBuild) -> TokenStream {
+    let child_ident = format_ident!("{}", name);
+    let child_type_ident = format_ident!("{}", node_child.kind());
+    quote! {
+        let mut #child_ident: Option<Box<#child_type_ident>> = None
+    }
+}
+
+fn make_boolean_child_holder(name: &str) -> TokenStream {
+    let child_ident = format_ident!("{}", name);
+    quote! {
+        let mut #child_ident: bool = false
+    }
+}
+
+fn make_child_holder(child_spec: &StructChild) -> Option<TokenStream> {
+    match child_spec {
+        StructChild::SkipChild(_) => None,
+        StructChild::VecChild(vec_child) => Some(make_vec_child_holder(vec_child)),
+        StructChild::MemberChild(member_child) => match member_child.build() {
+            MemberChildBuild::Node(node_child) => {
+                Some(make_node_child_holder(member_child.name(), node_child))
+            }
+            MemberChildBuild::Boolean(_) => Some(make_boolean_child_holder(member_child.name())),
+        },
+        StructChild::Special(_) => None,
+    }
+}
+
+fn make_vec_child_match_action(vec_child: &VecChild) -> TokenStream {
+    let child_name_ident = format_ident!("{}", vec_child.name());
+    match vec_child.build() {
+        VecChildBuild::String(string_build) => {
+            let build_fn_ident = format_ident!("{}", string_build.with());
+            quote! {
+                #child_name_ident.push(#build_fn_ident(file_id, inner_pair))
+            }
+        }
+        VecChildBuild::Node(node_build) => {
+            let build_fn_ident = format_ident!("{}", node_build.with());
+            quote! {
+                #child_name_ident.push(Box::new(#build_fn_ident(file_id, inner_pair)))
+            }
+        }
+    }
+}
+
+fn make_node_member_child_match_action(name: &str, node_child: &NodeMemberBuild) -> TokenStream {
+    let child_name_ident = format_ident!("{}", name);
+    let build_fn_ident = format_ident!("{}", node_child.with());
+    quote! {
+        #child_name_ident = Some(Box::new(#build_fn_ident(file_id, inner_pair)))
+    }
+}
+
+fn make_boolean_member_child_match_action(name: &str) -> TokenStream {
+    let child_name_ident = format_ident!("{}", name);
+    quote! {
+        #child_name_ident = true
+    }
+}
+
+fn make_rule_matcher(child_spec: &StructChild) -> Option<TokenStream> {
+    match child_spec {
+        StructChild::SkipChild(skip_child) => {
+            let rule_ident = format_ident!("{}", skip_child.rule());
+            Some(quote! {
+                Rule::#rule_ident => {}
+            })
+        }
+        StructChild::VecChild(vec_child) => {
+            let rule_ident = format_ident!("{}", vec_child.rule());
+            let action = make_vec_child_match_action(vec_child);
+            Some(quote! {
+                Rule::#rule_ident => { #action }
+            })
+        }
+        StructChild::MemberChild(member_child) => match member_child.build() {
+            MemberChildBuild::Node(node_member_build) => {
+                let rule_ident = format_ident!("{}", member_child.rule());
+                let action =
+                    make_node_member_child_match_action(member_child.name(), node_member_build);
+                Some(quote! {
+                    Rule::#rule_ident => { #action }
+                })
+            }
+            MemberChildBuild::Boolean(_) => {
+                let rule_ident = format_ident!("{}", member_child.rule());
+                let action = make_boolean_member_child_match_action(member_child.name());
+                Some(quote! {
+                    Rule::#rule_ident => { #action }
+                })
+            }
+        },
+        StructChild::Special(_) => None,
+    }
+}
+
+fn make_vec_child_arg(vec_child: &VecChild) -> TokenStream {
+    let child_ident = format_ident!("{}", vec_child.name());
+    quote! { #child_ident }
+}
+
+fn make_node_member_child_arg(
+    name: &str,
+    optional: bool,
+    node_child: &NodeMemberBuild,
+) -> TokenStream {
+    let child_ident = format_ident!("{}", name);
+    if optional {
+        quote! { #child_ident }
+    } else if let Some(or_else) = node_child.or_else() {
+        let child_type_ident = format_ident!("{}", node_child.kind());
+        let or_else_ident = format_ident!("{}", or_else);
+        quote! {
+            #child_ident.unwrap_or_else(|| Box::new(#child_type_ident::#or_else_ident()))
+        }
+    } else {
+        quote! { #child_ident.unwrap() }
+    }
+}
+
+fn make_boolean_member_child_arg(name: &str) -> TokenStream {
+    let child_ident = format_ident!("{}", name);
+    quote! { #child_ident }
+}
+
+fn make_special_child_arg(special_child: &SpecialChild) -> TokenStream {
+    let child_ident = format_ident!("{}", special_child.name());
+    quote! { #child_ident }
+}
+
+fn make_child_arg(child_spec: &StructChild, pair_ident: &Ident) -> Option<TokenStream> {
+    match child_spec {
+        StructChild::SkipChild(_) => None,
+        StructChild::VecChild(vec_child) => Some(make_vec_child_arg(vec_child)),
+        StructChild::MemberChild(member_child) => match member_child.build() {
+            MemberChildBuild::Node(node_member_build) => Some(make_node_member_child_arg(
+                member_child.name(),
+                member_child.optional(),
+                node_member_build,
+            )),
+            MemberChildBuild::Boolean(_) => {
+                Some(make_boolean_member_child_arg(member_child.name()))
+            }
+        },
+        StructChild::Special(special_child) => Some(make_special_child_arg(special_child)),
+    }
+}
+
+fn make_return_value_stream(build_spec: &StructSpec, pair_ident: &Ident) -> TokenStream {
+    let type_ident = format_ident!("{}", build_spec.build());
+    let child_args = build_spec
+        .children()
+        .map(|child| make_child_arg(child, pair_ident))
+        .filter(|child_arg| child_arg.is_some())
+        .map(|child_arg| child_arg.unwrap())
+        .collect::<Vec<_>>();
+
+    quote! {
+        #type_ident::new(
+            #(#child_args,)*
+        )
+    }
+}
+
+pub fn make_struct_build_fn(build_spec: &StructSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(build_spec.build()));
+    let pair_ident = format_ident!("{}", make_build_pair(build_spec.build()));
+    let return_type_ident = format_ident!("{}", build_spec.build());
+
+    let preamble = make_preamble(build_spec, &pair_ident);
+
+    let special_children = make_special_children(build_spec);
+
+    let child_holders = build_spec
+        .children()
+        .map(|child_spec| make_child_holder(child_spec))
+        .filter(|child_holder| child_holder.is_some())
+        .map(|child_holder| child_holder.unwrap())
+        .collect::<Vec<_>>();
+
+    let rule_matchers = build_spec
+        .children()
+        .map(|child_spec| make_rule_matcher(child_spec))
+        .collect::<Vec<_>>();
+
+    let iter_stream = quote! {
+        for inner_pair in #pair_ident.into_inner() {
+            match inner_pair.as_rule() {
+                #(#rule_matchers)*
+                _ => panic!("Unexpected rule: {:?}", inner_pair.as_rule())
+            }
+        }
+    };
+
+    let new_stream = make_return_value_stream(build_spec, &pair_ident);
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            #preamble
+
+            #(#special_children;)*
+
+            #(#child_holders;)*
+
+            #iter_stream
+
+            #new_stream
+        }
+    }
+}

ast-generator/src/build_fn/tree_enum_build_fn.rs

@@ -0,0 +1,63 @@
+use crate::deserialize::util::{make_build_fn_name, make_build_pair};
+use crate::spec::tree_enum_spec::{EnumRuleChildKind, TreeEnumBuildSpec};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_enum_build_fn(enum_build_spec: &TreeEnumBuildSpec) -> TokenStream {
+    let build_fn_ident = format_ident!("{}", make_build_fn_name(enum_build_spec.build()));
+    let pair_ident = format_ident!("{}", make_build_pair(enum_build_spec.build()));
+    let return_type_ident = format_ident!("{}", enum_build_spec.build());
+
+    let rule_branches = enum_build_spec
+        .rules()
+        .map(|enum_rule| {
+            let rule_ident = format_ident!("{}", enum_rule.rule());
+            if let Some(child) = enum_rule.child() {
+                let inner_builder = match child.kind() {
+                    EnumRuleChildKind::Node(node_child) => {
+                        let inner_build_fn_ident =
+                            format_ident!("{}", node_child.with());
+                        quote! { #inner_build_fn_ident(file_id, inner_pair) }
+                    }
+                    EnumRuleChildKind::Int(name_and_with) => {
+                        let inner_build_fn_ident = format_ident!("{}", name_and_with.with());
+                        quote! { #inner_build_fn_ident(file_id, inner_pair) }
+                    }
+                    EnumRuleChildKind::Long(name_and_with) => {
+                        let inner_build_fn_ident = format_ident!("{}", name_and_with.with());
+                        quote! { #inner_build_fn_ident(file_id, inner_pair) }
+                    }
+                    EnumRuleChildKind::Double(name_and_with) => {
+                        let inner_build_fn_ident = format_ident!("{}", name_and_with.with());
+                        quote! { #inner_build_fn_ident(file_id, inner_pair) }
+                    }
+                    EnumRuleChildKind::String(name_and_with) => {
+                        let inner_build_fn_ident = format_ident!("{}", name_and_with.with());
+                        quote! { #inner_build_fn_ident(file_id, inner_pair) }
+                    }
+                    EnumRuleChildKind::Boolean(name_and_with) => {
+                        let inner_build_fn_ident = format_ident!("{}", name_and_with.with());
+                        quote! { #inner_build_fn_ident(file_id, inner_pair) }
+                    }
+                };
+                quote! {
+                    Rule::#rule_ident => #return_type_ident::#rule_ident(#inner_builder)
+                }
+            } else {
+                quote! {
+                    Rule::#rule_ident => #return_type_ident::#rule_ident
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
+            let inner_pair = #pair_ident.into_inner().next().unwrap();
+            match inner_pair.as_rule() {
+                #(#rule_branches,)*
+                _ => unreachable!()
+            }
+        }
+    }
+}

ast-generator/src/build_fn_gen.rs

@@ -1,127 +0,0 @@
-use crate::spec::{
-    BuildBooleanOn, ChildSpec, SingleChildToBuild, StructBuildSpec, VecChildToBuild,
-};
-use convert_case::{Case, Casing};
-use proc_macro2::TokenStream;
-use quote::{format_ident, quote};
-
-pub fn make_build_fn_name(s: &str) -> String {
-    format!("build_{}", s.to_case(Case::Snake))
-}
-
-fn make_child_holder(child_spec: &ChildSpec) -> Option<TokenStream> {
-    match child_spec {
-        ChildSpec::SkipChild(_) => None,
-        ChildSpec::VecChild(vec_child) => {
-            let (child_ident, child_type_ident) = match vec_child.build() {
-                VecChildToBuild::Type(vec_type_child) => (
-                    format_ident!("{}", vec_type_child.var_name()),
-                    format_ident!("{}", vec_type_child.build()),
-                ),
-            };
-            Some(quote! {
-                let mut #child_ident: Vec<#child_type_ident> = vec![]
-            })
-        }
-        ChildSpec::SingleChild(single_child) => match single_child.build() {
-            SingleChildToBuild::Type(single_type_child) => {
-                let child_ident = format_ident!("{}", single_type_child.var_name());
-                let child_type_ident = format_ident!("{}", single_type_child.build());
-                Some(quote! {
-                    let mut #child_ident: Option<#child_type_ident> = None;
-                })
-            }
-            SingleChildToBuild::Boolean(boolean_child) => {
-                let child_ident = format_ident!("{}", boolean_child.var_name());
-                Some(quote! {
-                    let #child_ident: bool = false
-                })
-            }
-        },
-    }
-}
-
-fn make_match_action(child_spec: &ChildSpec) -> TokenStream {
-    match child_spec {
-        ChildSpec::SkipChild(_) => quote! {},
-        ChildSpec::VecChild(vec_child) => {
-            let (child_name_ident, build_fn_ident) = match vec_child.build() {
-                VecChildToBuild::Type(vec_type_child) => (
-                    format_ident!("{}", vec_type_child.var_name()),
-                    format_ident!("{}", vec_type_child.with()),
-                ),
-            };
-            quote! {
-                #child_name_ident.push(#build_fn_ident(inner_pair))
-            }
-        }
-        ChildSpec::SingleChild(single_child) => match single_child.build() {
-            SingleChildToBuild::Type(single_type_child) => {
-                let child_name_ident = format_ident!("{}", single_type_child.var_name());
-                let build_fn_ident = format_ident!("{}", single_type_child.with());
-                quote! {
-                    #child_name_ident = Some(#build_fn_ident(inner_pair))
-                }
-            }
-            SingleChildToBuild::Boolean(single_boolean_child) => {
-                let child_name_ident = format_ident!("{}", single_boolean_child.var_name());
-                match single_boolean_child.on() {
-                    BuildBooleanOn::RulePresent => quote! {
-                        #child_name_ident = true
-                    },
-                }
-            }
-        },
-    }
-}
-
-fn make_rule_matcher(child_spec: &ChildSpec) -> TokenStream {
-    let rule_ident = match child_spec {
-        ChildSpec::SkipChild(skip_child) => format_ident!("{}", skip_child.rule()),
-        ChildSpec::VecChild(vec_child) => format_ident!("{}", vec_child.rule()),
-        ChildSpec::SingleChild(single_child) => format_ident!("{}", single_child.rule()),
-    };
-    let action = make_match_action(child_spec);
-
-    quote! {
-        Rule::#rule_ident => {
-            #action;
-        }
-    }
-}
-
-pub fn make_struct_build_fn(build_spec: &StructBuildSpec) -> TokenStream {
-    let build_fn_ident = format_ident!("{}", build_spec.with());
-    let pair_ident = format_ident!("{}_pair", build_spec.build().to_case(Case::Snake));
-    let return_type_ident = format_ident!("{}", build_spec.build());
-
-    let child_holders = build_spec
-        .children()
-        .iter()
-        .map(|child_spec| make_child_holder(child_spec))
-        .filter(|child_holder| child_holder.is_some())
-        .map(|child_holder| child_holder.unwrap())
-        .collect::<Vec<_>>();
-
-    let rule_matchers = build_spec
-        .children()
-        .iter()
-        .map(|child_spec| make_rule_matcher(child_spec))
-        .collect::<Vec<_>>();
-
-    let iter_stream = quote! {
-        for inner_pair in #pair_ident.into_inner() {
-            match inner_pair.as_rule() {
-                #(#rule_matchers)*
-            }
-        }
-    };
-
-    quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
-            #(#child_holders;)*
-
-            #iter_stream
-        }
-    }
-}

ast-generator/src/deserialize.rs

@@ -1,168 +0,0 @@
-use crate::build_fn_gen::make_build_fn_name;
-use crate::spec::{
-    BuildBooleanOn, BuildSpec, ChildSpec, EnumBuildSpec, EnumRule, SingleBooleanChildToBuild,
-    SingleChild, SingleChildToBuild, SingleTypeChildToBuild, SkipChild, StructBuildSpec, VecChild,
-    VecChildToBuild, VecTypeChildToBuild,
-};
-use convert_case::{Case, Casing};
-use yaml_rust2::{Yaml, YamlLoader};
-
-fn get_skip(skip: &Yaml) -> bool {
-    skip.as_bool().unwrap_or_else(|| false)
-}
-
-fn get_vec(vec: &Yaml) -> bool {
-    vec.as_bool().unwrap_or_else(|| false)
-}
-
-fn get_vec_child_to_build(build: &Yaml, name: &str, rule: &str) -> VecChildToBuild {
-    if build.is_hash() {
-        let build_type = build["build"].as_str().unwrap();
-        let var_name = build["var"]
-            .as_str()
-            .map(|s| s.to_string())
-            .unwrap_or_else(|| build_type.to_case(Case::Snake));
-        let with = build["with"]
-            .as_str()
-            .map(|s| s.to_string())
-            .unwrap_or_else(|| make_build_fn_name(build_type));
-
-        VecChildToBuild::Type(VecTypeChildToBuild::new(build_type, &var_name, &with))
-    } else {
-        let build_as_str = build.as_str().unwrap_or(rule);
-        VecChildToBuild::Type(VecTypeChildToBuild::new(
-            build_as_str,
-            name,
-            make_build_fn_name(build_as_str).as_str(),
-        ))
-    }
-}
-
-fn get_vec_child(name: &str, rule: &str, build: &Yaml) -> ChildSpec {
-    ChildSpec::VecChild(VecChild::new(
-        name,
-        rule,
-        get_vec_child_to_build(build, name, rule),
-    ))
-}
-
-fn get_single_child_to_build(name: &str, rule: &str, build: &Yaml) -> SingleChildToBuild {
-    if build.is_hash() {
-        let r#type = build["type"].as_str().unwrap();
-        let var_name = build["var"]
-            .as_str()
-            .map(|s| s.to_string())
-            .unwrap_or(name.to_string());
-        let on = build["on"].as_str().unwrap();
-        if r#type.eq("boolean") && on.eq("rule_present") {
-            SingleChildToBuild::Boolean(SingleBooleanChildToBuild::new(
-                &var_name,
-                BuildBooleanOn::RulePresent,
-            ))
-        } else {
-            todo!("currently on boolean types with on: rule_present are supported")
-        }
-    } else {
-        match build.as_str() {
-            Some(s) => SingleChildToBuild::Type(SingleTypeChildToBuild::from_build_or_rule(s)),
-            None => SingleChildToBuild::Type(SingleTypeChildToBuild::from_build_or_rule(rule)),
-        }
-    }
-}
-
-fn get_single_child(name: &str, rule: &str, build: &Yaml) -> ChildSpec {
-    ChildSpec::SingleChild(SingleChild::new(
-        name,
-        rule,
-        get_single_child_to_build(name, rule, build),
-    ))
-}
-
-fn get_child_specs(children: &Yaml) -> Vec<ChildSpec> {
-    children
-        .as_vec()
-        .unwrap()
-        .iter()
-        .map(|child_spec| {
-            if child_spec.is_hash() {
-                let as_hash = child_spec.as_hash().unwrap();
-                let (name, props) = as_hash
-                    .iter()
-                    .next()
-                    .map(|(name, props)| (name.as_str().unwrap(), props))
-                    .unwrap();
-
-                let rule = props["rule"].as_str().unwrap();
-
-                if get_skip(&props["skip"]) {
-                    return ChildSpec::SkipChild(SkipChild::new(name, rule));
-                }
-
-                let build = &props["build"];
-
-                if get_vec(&props["vec"]) {
-                    get_vec_child(name, rule, build)
-                } else {
-                    get_single_child(name, rule, build)
-                }
-            } else {
-                ChildSpec::SingleChild(SingleChild::from_name_snake(child_spec.as_str().unwrap()))
-            }
-        })
-        .collect()
-}
-
-fn get_enum_rule_specs(rule_specs: &Yaml) -> Vec<EnumRule> {
-    rule_specs
-        .as_vec()
-        .unwrap()
-        .iter()
-        .map(|rule_spec| {
-            if rule_spec.is_hash() {
-                let rule = rule_spec["rule"].as_str().unwrap();
-                let build = rule_spec["build"].as_str().unwrap();
-                let with = if !rule_spec["with"].is_badvalue() {
-                    rule_spec.as_str().unwrap().to_string()
-                } else {
-                    make_build_fn_name(build)
-                };
-
-                EnumRule::new(rule, build, &with)
-            } else {
-                EnumRule::from_rule(rule_spec.as_str().unwrap())
-            }
-        })
-        .collect()
-}
-
-fn deserialize_build_spec(build_spec_name: &Yaml, build_spec: &Yaml) -> BuildSpec {
-    let build_spec_name_pascal = build_spec_name.as_str().unwrap();
-    let children = &build_spec["children"];
-
-    if children.is_array() {
-        let child_specs = get_child_specs(children);
-        BuildSpec::Struct(StructBuildSpec::from_name(
-            build_spec_name_pascal,
-            child_specs,
-        ))
-    } else {
-        let rule_specs = &build_spec["rules"];
-        if rule_specs.is_array() {
-            let enum_rules = get_enum_rule_specs(rule_specs);
-            BuildSpec::Enum(EnumBuildSpec::from_name(build_spec_name_pascal, enum_rules))
-        } else {
-            panic!("either children or rules must be present on the build spec");
-        }
-    }
-}
-
-pub fn deserialize_yaml_spec(yaml: &str) -> Vec<BuildSpec> {
-    let docs = YamlLoader::load_from_str(yaml).unwrap();
-    let doc = &docs[0];
-
-    doc.as_hash()
-        .unwrap()
-        .iter()
-        .map(|(build_spec_name, build_spec)| deserialize_build_spec(build_spec_name, build_spec))
-        .collect()
-}

ast-generator/src/deserialize/leaf_enum_spec.rs

@@ -0,0 +1,13 @@
+use yaml_rust2::Yaml;
+use crate::spec::leaf_enum_spec::LeafEnumBuildSpec;
+
+pub fn deserialize_leaf_enum(name: &str, props: &Yaml) -> LeafEnumBuildSpec {
+    let rules = props["rules"].as_vec()
+        .unwrap()
+        .iter()
+        .map(|rule_yaml| {
+            rule_yaml.as_str().unwrap().to_string()
+        })
+        .collect();
+    LeafEnumBuildSpec::new(name, rules)
+}

ast-generator/src/deserialize/leaf_struct_spec.rs

@@ -0,0 +1,37 @@
+use crate::deserialize::util::unwrap_single_member_hash;
+use yaml_rust2::Yaml;
+use crate::spec::leaf_struct_spec::{LeafStructBuildSpec, LeafStructMember, LeafStructMemberKind};
+
+fn deserialize_member(member_name: &str, member_props: &Yaml) -> LeafStructMember {
+    let kind = match member_props["kind"].as_str().unwrap() {
+        "string" => LeafStructMemberKind::String,
+        "file_id" => LeafStructMemberKind::FileId,
+        "range" => LeafStructMemberKind::Range,
+        _ => panic!()
+    };
+    LeafStructMember::new(member_name, kind)
+}
+
+pub fn deserialize_leaf_struct(name: &str, props: &Yaml) -> LeafStructBuildSpec {
+    let members = props["members"]
+        .as_vec()
+        .unwrap()
+        .iter()
+        .map(|member_hash| {
+            let (member_name, props) = unwrap_single_member_hash(member_hash);
+            deserialize_member(&member_name, props)
+        })
+        .map(Box::new)
+        .collect();
+    let derive = props["derive"]
+        .as_vec()
+        .map(|derive_yaml| {
+            derive_yaml.iter()
+                .map(|trait_yaml| { 
+                    trait_yaml.as_str().unwrap().to_string() 
+                }).collect::<Vec<_>>()
+        })
+        .unwrap_or_default();
+    
+    LeafStructBuildSpec::new(name, members, derive)
+}

ast-generator/src/deserialize/mod.rs

@@ -0,0 +1,108 @@
+mod leaf_enum_spec;
+mod leaf_struct_spec;
+mod node_production_spec;
+mod polymorphic_enum_build_inner;
+mod polymorphic_enum_loop_spec;
+mod polymorphic_leaf_enum;
+mod polymorphic_pass_through_spec;
+mod polymorphic_tree_enum;
+mod polymorphic_type_spec;
+mod production_spec;
+mod struct_spec;
+mod tree_enum_spec;
+pub(crate) mod util;
+
+use crate::deserialize::leaf_enum_spec::deserialize_leaf_enum;
+use crate::deserialize::leaf_struct_spec::deserialize_leaf_struct;
+use crate::deserialize::node_production_spec::deserialize_node_production;
+use crate::deserialize::polymorphic_enum_build_inner::deserialize_polymorphic_enum_inner_build;
+use crate::deserialize::polymorphic_enum_loop_spec::deserialize_polymorphic_enum_loop;
+use crate::deserialize::polymorphic_leaf_enum::deserialize_polymorphic_leaf_enum;
+use crate::deserialize::polymorphic_pass_through_spec::deserialize_polymorphic_pass_through;
+use crate::deserialize::polymorphic_type_spec::deserialize_polymorphic_type;
+use crate::deserialize::production_spec::deserialize_production;
+use crate::deserialize::struct_spec::deserialize_struct_spec;
+use crate::deserialize::tree_enum_spec::deserialize_tree_enum;
+use crate::spec::BuildSpec;
+use yaml_rust2::{Yaml, YamlLoader};
+use crate::deserialize::polymorphic_tree_enum::deserialize_polymorphic_tree_enum;
+
+fn deserialize_build_spec(build_spec_name: &str, build_spec: &Yaml) -> BuildSpec {
+    if build_spec["struct"].is_hash() {
+        BuildSpec::Struct(deserialize_struct_spec(
+            build_spec_name,
+            &build_spec["struct"],
+        ))
+    } else if build_spec["leaf_struct"].is_hash() {
+        BuildSpec::LeafStruct(deserialize_leaf_struct(
+            build_spec_name,
+            &build_spec["leaf_struct"],
+        ))
+    } else if build_spec["tree_enum"].is_hash() {
+        BuildSpec::Enum(deserialize_tree_enum(
+            build_spec_name,
+            &build_spec["tree_enum"],
+        ))
+    } else if build_spec["leaf_enum"].is_hash() {
+        BuildSpec::LeafEnum(deserialize_leaf_enum(
+            build_spec_name,
+            &build_spec["leaf_enum"],
+        ))
+    } else if build_spec["production"].is_hash() {
+        BuildSpec::Production(deserialize_production(
+            build_spec_name,
+            &build_spec["production"],
+        ))
+    } else if build_spec["node_production"].is_hash() {
+        BuildSpec::NodeProduction(deserialize_node_production(
+            build_spec_name,
+            &build_spec["node_production"],
+        ))
+    } else if build_spec["polymorphic_type"].is_hash() {
+        BuildSpec::PolymorphicType(deserialize_polymorphic_type(
+            build_spec_name,
+            &build_spec["polymorphic_type"],
+        ))
+    } else if build_spec["polymorphic_enum_loop_build"].is_hash() {
+        BuildSpec::PolymorphicEnumLoop(deserialize_polymorphic_enum_loop(
+            build_spec_name,
+            &build_spec["polymorphic_enum_loop_build"],
+        ))
+    } else if build_spec["polymorphic_pass_through"].is_hash() {
+        BuildSpec::PolymorphicPassThrough(deserialize_polymorphic_pass_through(
+            build_spec_name,
+            &build_spec["polymorphic_pass_through"],
+        ))
+    } else if build_spec["polymorphic_enum_inner_build"].is_hash() {
+        BuildSpec::PolymorphicEnumInnerBuild(deserialize_polymorphic_enum_inner_build(
+            build_spec_name,
+            &build_spec["polymorphic_enum_inner_build"],
+        ))
+    } else if build_spec["polymorphic_leaf_enum"].is_hash() {
+        BuildSpec::PolymorphicLeafEnum(deserialize_polymorphic_leaf_enum(
+            build_spec_name,
+            &build_spec["polymorphic_leaf_enum"],
+        ))
+    } else if build_spec["polymorphic_tree_enum"].is_hash() {
+        BuildSpec::PolymorphicTreeEnum(deserialize_polymorphic_tree_enum(
+            build_spec_name,
+            &build_spec["polymorphic_tree_enum"],
+        ))
+    } else {
+        panic!("Missing or incorrect build type for {}", build_spec_name);
+    }
+}
+
+pub fn deserialize_yaml_spec(yaml: &str) -> Vec<BuildSpec> {
+    let docs = YamlLoader::load_from_str(yaml).unwrap();
+    let doc = &docs[0];
+
+    doc.as_hash()
+        .unwrap()
+        .iter()
+        .map(|(build_spec_name, build_spec)| {
+            let name_as_str = build_spec_name.as_str().unwrap();
+            deserialize_build_spec(name_as_str, build_spec)
+        })
+        .collect()
+}

ast-generator/src/deserialize/node_production_spec.rs

@@ -0,0 +1,9 @@
+use crate::deserialize::util::make_build_fn_name;
+use crate::spec::node_production_spec::NodeProductionBuildSpec;
+use yaml_rust2::Yaml;
+
+pub fn deserialize_node_production(name: &str, props: &Yaml) -> NodeProductionBuildSpec {
+    let kind = props["kind"].as_str().unwrap();
+    let with = make_build_fn_name(props["with"].as_str().unwrap());
+    NodeProductionBuildSpec::new(name, kind, &with)
+}

ast-generator/src/deserialize/polymorphic_enum_build_inner.rs

@@ -0,0 +1,59 @@
+use crate::deserialize::util::{make_build_fn_name, unwrap_single_member_hash};
+use crate::spec::polymorphic_enum_inner_build::{
+    PolymorphicEnumInnerBuild, PolymorphicEnumInnerBuildMember,
+    PolymorphicEnumInnerBuildMemberKind, PolymorphicEnumInnerBuildRule,
+};
+use yaml_rust2::Yaml;
+
+pub fn deserialize_polymorphic_enum_inner_build(
+    name: &str,
+    props: &Yaml,
+) -> PolymorphicEnumInnerBuild {
+    let members = props["members"]
+        .as_vec()
+        .unwrap()
+        .iter()
+        .map(|member| {
+            if let Some(name) = member.as_str() {
+                PolymorphicEnumInnerBuildMember::new(
+                    name,
+                    PolymorphicEnumInnerBuildMemberKind::Struct,
+                )
+            } else if member.is_hash() {
+                let (name, props) = unwrap_single_member_hash(member);
+                if let Some(kind) = props["kind"].as_str() {
+                    match kind {
+                        "leaf" => PolymorphicEnumInnerBuildMember::new(
+                            &name,
+                            PolymorphicEnumInnerBuildMemberKind::Leaf,
+                        ),
+                        "struct" => PolymorphicEnumInnerBuildMember::new(
+                            &name,
+                            PolymorphicEnumInnerBuildMemberKind::Struct,
+                        ),
+                        _ => panic!(),
+                    }
+                } else {
+                    panic!()
+                }
+            } else {
+                panic!()
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let rules = props["rules"]
+        .as_vec()
+        .unwrap()
+        .iter()
+        .map(|rule| {
+            let rule_as_string = rule.as_str().unwrap().to_string();
+            PolymorphicEnumInnerBuildRule::new(
+                &rule_as_string,
+                &make_build_fn_name(&rule_as_string),
+            )
+        })
+        .collect::<Vec<_>>();
+
+    PolymorphicEnumInnerBuild::new(name, members, rules)
+}

ast-generator/src/deserialize/polymorphic_enum_loop_spec.rs

@@ -0,0 +1,102 @@
+use crate::deserialize::util::{get_as_bool, make_build_fn_name, unwrap_single_member_hash};
+use crate::spec::polymorphic_enum_loop_spec::{
+    PolymorphicEnumLoopBuildSpec, PolymorphicEnumLoopChildUseCurrent, PolymorphicEnumLoopRule,
+    PolymorphicEnumLoopRuleBuild, PolymorphicEnumLoopRuleBuildChild,
+    PolymorphicEnumLoopRuleChildOnEach, PolymorphicEnumLoopRulePassThrough,
+};
+use crate::spec::{SpecialChild, SpecialChildKind, StructField};
+use yaml_rust2::Yaml;
+
+fn deserialize_build_child(child_name: &str, props: &Yaml) -> PolymorphicEnumLoopRuleBuildChild {
+    if props["use_current"].is_hash() {
+        let kind = props["use_current"]["kind"].as_str().unwrap();
+        PolymorphicEnumLoopRuleBuildChild::UseCurrent(PolymorphicEnumLoopChildUseCurrent::new(
+            child_name, kind,
+        ))
+    } else if props["on_each"].is_hash() {
+        let rule = props["on_each"]["rule"].as_str().unwrap();
+        PolymorphicEnumLoopRuleBuildChild::OnEach(PolymorphicEnumLoopRuleChildOnEach::new(
+            child_name, rule,
+        ))
+    } else if props["special"].is_hash() {
+        let kind = match props["special"]["kind"].as_str().unwrap() {
+            "range" => SpecialChildKind::Range,
+            "file_id" => SpecialChildKind::FileId,
+            _ => panic!("Unknown special child kind"),
+        };
+        PolymorphicEnumLoopRuleBuildChild::Special(SpecialChild::new(child_name, kind))
+    } else {
+        panic!("Expected 'use_current' or 'on_each' hash for polymorphic enum loop build child");
+    }
+}
+
+fn deserialize_build(name: &str, props: &Yaml) -> PolymorphicEnumLoopRuleBuild {
+    let variant = props["variant"].as_str().unwrap();
+    let children = props["children"]
+        .as_vec()
+        .unwrap()
+        .iter()
+        .map(|child_yaml| {
+            let (child_name, child_props) = unwrap_single_member_hash(child_yaml);
+            deserialize_build_child(&child_name, child_props)
+        })
+        .map(Box::new)
+        .collect();
+
+    let fields = props["fields"]
+        .as_vec()
+        .map(|fields| {
+            fields.iter()
+                .map(|field_yaml| {
+                    let (field_name, field_props) = unwrap_single_member_hash(field_yaml);
+                    let kind = field_props["kind"].as_str().unwrap();
+                    StructField::new(
+                        &field_name,
+                        kind,
+                        None,
+                        false
+                    )
+                })
+                .collect::<Vec<_>>()
+        })
+        .unwrap_or_else(|| vec![]);
+    
+    PolymorphicEnumLoopRuleBuild::new(name, variant, children, fields)
+}
+
+fn deserialize_pass_through(name: &str, props: &Yaml) -> PolymorphicEnumLoopRulePassThrough {
+    let kind = props["kind"].as_str().unwrap();
+    let with = make_build_fn_name(props["with"].as_str().unwrap_or(kind));
+    PolymorphicEnumLoopRulePassThrough::new(name, kind, &with)
+}
+
+fn deserialize_rule(rule_name: &str, props: &Yaml) -> PolymorphicEnumLoopRule {
+    if props["pass_through"].is_hash() {
+        PolymorphicEnumLoopRule::PassThrough(deserialize_pass_through(
+            rule_name,
+            &props["pass_through"],
+        ))
+    } else if props["build"].is_hash() {
+        PolymorphicEnumLoopRule::Build(deserialize_build(rule_name, &props["build"]))
+    } else {
+        panic!("Polymorphic enum loop rule must have 'pass_through' or 'build' hash.");
+    }
+}
+
+pub fn deserialize_polymorphic_enum_loop(name: &str, props: &Yaml) -> PolymorphicEnumLoopBuildSpec {
+    let kind = props["kind"].as_str().unwrap();
+    let reverse = get_as_bool(&props["reverse"]);
+
+    let rules = props["rules"]
+        .as_vec()
+        .unwrap()
+        .iter()
+        .map(|rule_yaml| {
+            let (rule_name, rule_props) = unwrap_single_member_hash(rule_yaml);
+            deserialize_rule(&rule_name, rule_props)
+        })
+        .map(Box::new)
+        .collect();
+
+    PolymorphicEnumLoopBuildSpec::new(name, kind, reverse, rules)
+}

ast-generator/src/deserialize/polymorphic_leaf_enum.rs

@@ -0,0 +1,13 @@
+use yaml_rust2::Yaml;
+use crate::spec::polymorphic_leaf_enum::PolymorphicLeafEnum;
+
+pub fn deserialize_polymorphic_leaf_enum(name: &str, props: &Yaml) -> PolymorphicLeafEnum {
+    let kind = props["kind"].as_str().unwrap();
+    let rules = props["rules"].as_vec().unwrap()
+        .iter()
+        .map(|rule| {
+            rule.as_str().unwrap().to_string()
+        })
+        .collect::<Vec<_>>();
+    PolymorphicLeafEnum::new(name, kind, rules)
+}

ast-generator/src/deserialize/polymorphic_pass_through_spec.rs

@@ -0,0 +1,30 @@
+use crate::deserialize::util::unwrap_single_member_hash;
+use crate::spec::polymorphic_pass_through_spec::{PolymorphicPassThroughBuildSpec, PolymorphicPassThroughVariant};
+use yaml_rust2::Yaml;
+
+pub fn deserialize_polymorphic_pass_through(name: &str, props: &Yaml) -> PolymorphicPassThroughBuildSpec {
+    let build_kind = props["build"]["kind"].as_str().unwrap();
+    let variants = props["variants"].as_vec().unwrap()
+        .iter()
+        .map(|variant_yaml| {
+            let (variant_name, variant_props) = unwrap_single_member_hash(variant_yaml);
+            if variant_props["inner"].is_hash() {
+                let inner_kind = variant_props["inner"]["kind"].as_str().unwrap();
+                PolymorphicPassThroughVariant::Inner {
+                    name: variant_name,
+                    kind: inner_kind.to_string(),
+                }
+            } else if variant_props["pass_through"].is_hash() {
+                let pass_through_kind = variant_props["pass_through"]["kind"].is_hash();
+                PolymorphicPassThroughVariant::PassThrough {
+                    name: variant_name,
+                    kind: pass_through_kind.to_string(),
+                }
+            } else {
+                panic!()
+            }
+        })
+        .map(Box::new)
+        .collect();
+    PolymorphicPassThroughBuildSpec::new(name, build_kind, variants)
+}

ast-generator/src/deserialize/polymorphic_tree_enum.rs

@@ -0,0 +1,12 @@
+use yaml_rust2::Yaml;
+use crate::spec::polymorphic_tree_enum_spec::PolymorphicTreeEnumSpec;
+
+pub fn deserialize_polymorphic_tree_enum(name: &str, props: &Yaml) -> PolymorphicTreeEnumSpec {
+    let kind = props["kind"].as_str().unwrap();
+    let rules = props["rules"].as_vec().unwrap()
+        .iter()
+        .map(|rule| rule.as_str().unwrap())
+        .collect::<Vec<_>>();
+    
+    PolymorphicTreeEnumSpec::new(name, kind, &rules)
+}

ast-generator/src/deserialize/polymorphic_type_spec.rs

@@ -0,0 +1,23 @@
+use crate::deserialize::util::unwrap_single_member_hash;
+use crate::spec::polymorphic_type_spec::{PolymorphicTypeBuildSpec, PolymorphicTypeVariant};
+use yaml_rust2::Yaml;
+
+fn deserialize_variant(variant_name: &str, props: &Yaml) -> PolymorphicTypeVariant {
+    let inner_kind = props["inner"]["kind"].as_str().unwrap();
+    PolymorphicTypeVariant::new(variant_name, inner_kind)    
+}
+
+pub fn deserialize_polymorphic_type(name: &str, props: &Yaml) -> PolymorphicTypeBuildSpec {
+    let variants = props["variants"]
+        .as_vec()
+        .unwrap()
+        .iter()
+        .map(|variant_yaml| {
+            let (variant_name, variant_props) = unwrap_single_member_hash(variant_yaml);
+            deserialize_variant(&variant_name, variant_props)
+        })
+        .map(Box::new)
+        .collect();
+    let kind = props["build"]["kind"].as_str().unwrap();
+    PolymorphicTypeBuildSpec::new(name, variants, kind)
+}

ast-generator/src/deserialize/production_spec.rs

@@ -0,0 +1,21 @@
+use crate::spec::production_spec::{ProductionBooleanFrom, ProductionBuildSpec, ProductionKind, ProductionStringFrom};
+use yaml_rust2::Yaml;
+
+pub fn deserialize_production(name: &str, props: &Yaml) -> ProductionBuildSpec {
+    let kind = match props["kind"].as_str().unwrap() {
+        "int" => ProductionKind::Int,
+        "long" => ProductionKind::Long,
+        "double" => ProductionKind::Double,
+        "string" => {
+            let from = match props["from"].as_str().unwrap() {
+                "string_inner" => ProductionStringFrom::StringInner,
+                "whole_pair" => ProductionStringFrom::WholePair,
+                _ => panic!("Unknown string production from: {}", props["from"].as_str().unwrap())
+            };
+            ProductionKind::String(from)
+        },
+        "boolean" => ProductionKind::Boolean(ProductionBooleanFrom::ParseWholePair),
+        _ => panic!("Unknown production kind: {}", props["kind"].as_str().unwrap()),
+    };
+    ProductionBuildSpec::new(name, kind)
+}

ast-generator/src/deserialize/struct_spec.rs

@@ -0,0 +1,199 @@
+use crate::deserialize_error;
+use convert_case::{Case, Casing};
+
+use crate::deserialize::util::{get_as_bool, make_build_fn_name, unwrap_single_member_hash};
+use crate::spec::struct_spec::*;
+use crate::spec::{SpecialChild, SpecialChildKind, StructField, StructFieldWrap};
+use yaml_rust2::Yaml;
+
+fn deserialize_field(field_yaml: &Yaml) -> StructField {
+    let (name, props) = unwrap_single_member_hash(field_yaml);
+    let kind = props["kind"].as_str().unwrap();
+    let wrap = if let Some(wrap) = props["wrap"].as_str() {
+        match wrap {
+            "rc_ref_cell" => Some(StructFieldWrap::RcRefCell),
+            _ => panic!(),
+        }
+    } else {
+        None
+    };
+    let vec = get_as_bool(&props["vec"]);
+    StructField::new(&name, kind, wrap, vec)
+}
+
+fn deserialize_skip_child(props: &Yaml) -> StructChild {
+    let rule = props["rule"].as_str().unwrap();
+    StructChild::SkipChild(SkipChild::new(rule))
+}
+
+fn deserialize_vec_child(child_name: &str, props: &Yaml) -> StructChild {
+    let rule = props["rule"].as_str().unwrap();
+    let kind = props["kind"].as_str().unwrap_or(rule);
+    if kind == "string" {
+        let build = VecChildBuild::String(VecChildStringBuild::new(&make_build_fn_name(rule)));
+        StructChild::VecChild(VecChild::new(child_name, rule, Box::new(build)))
+    } else {
+        let build = VecChildBuild::Node(VecChildNodeBuild::new(rule, &make_build_fn_name(rule)));
+        StructChild::VecChild(VecChild::new(child_name, rule, Box::new(build)))
+    }
+}
+
+fn deserialize_member_build(child_name: &str, rule: &str, props: &Yaml) -> MemberChildBuild {
+    if props["node"].is_hash() {
+        let node_props = &props["node"];
+        let kind = node_props["kind"].as_str().unwrap_or(rule);
+        let with = node_props["with"]
+            .as_str()
+            .map(|with| make_build_fn_name(with))
+            .unwrap_or_else(|| make_build_fn_name(kind));
+
+        let or_else = if get_as_bool(&node_props["or_else_default"]) {
+            Some(String::from("default"))
+        } else if let Some(or_else) = node_props["or_else"].as_str() {
+            Some(or_else.to_string())
+        } else {
+            None
+        };
+
+        MemberChildBuild::Node(NodeMemberBuild::new(kind, &with, or_else))
+    } else if props["boolean"].is_hash() {
+        let boolean_props = &props["boolean"];
+        if let Some(on) = boolean_props["on"].as_str() {
+            if on == "rule_present" {
+                MemberChildBuild::Boolean(BooleanMemberBuild::new(
+                    BooleanMemberBuildOn::RulePresent,
+                ))
+            } else {
+                panic!(
+                    "Expected 'on' in 'boolean' in 'build' in {} to be 'rule_present'",
+                    child_name
+                );
+            }
+        } else {
+            panic!("Expected 'on' in 'boolean' in 'build' in {}", child_name);
+        }
+    } else {
+        panic!(
+            "Expected one of 'node', 'boolean', or 'special' in 'build' in {}",
+            child_name
+        );
+    }
+}
+
+fn deserialize_member_child(child_name: &str, props: &Yaml) -> StructChild {
+    let rule = props["rule"]
+        .as_str()
+        .map(ToString::to_string)
+        .unwrap_or_else(|| child_name.to_case(Case::Pascal));
+    let optional = get_as_bool(&props["optional"]);
+    if props["build"].is_hash() {
+        let build = deserialize_member_build(child_name, &rule, &props["build"]);
+        StructChild::MemberChild(MemberChild::new(
+            child_name,
+            &rule,
+            optional,
+            Box::new(build),
+        ))
+    } else {
+        StructChild::MemberChild(MemberChild::new(
+            child_name,
+            &rule,
+            optional,
+            Box::new(MemberChildBuild::Node(NodeMemberBuild::new(
+                &rule,
+                &make_build_fn_name(&rule),
+                None,
+            ))),
+        ))
+    }
+}
+
+fn deserialize_special_child(name: &str, props: &Yaml) -> StructChild {
+    match props["kind"].as_str().unwrap() {
+        "file_id" => StructChild::Special(SpecialChild::new(name, SpecialChildKind::FileId)),
+        "range" => StructChild::Special(SpecialChild::new(name, SpecialChildKind::Range)),
+        _ => panic!(
+            "Invalid special child kind {} in {}",
+            props["kind"].as_str().unwrap(),
+            name
+        ),
+    }
+}
+
+fn deserialize_hash_child(name: &str, props: &Yaml) -> StructChild {
+    if props["skip"].is_hash() {
+        deserialize_skip_child(&props["skip"])
+    } else if props["vec"].is_hash() {
+        deserialize_vec_child(name, &props["vec"])
+    } else if props["member"].is_hash() {
+        deserialize_member_child(name, &props["member"])
+    } else if props["special"].is_hash() {
+        deserialize_special_child(name, &props["special"])
+    } else {
+        panic!("Expected 'skip' or 'vec' in 'member' in {}", name);
+    }
+}
+
+fn deserialize_string_child(name: &str) -> StructChild {
+    let name_pascal = name.to_case(Case::Pascal);
+    StructChild::MemberChild(MemberChild::new(
+        name,
+        &name_pascal,
+        false,
+        Box::new(MemberChildBuild::Node(NodeMemberBuild::new(
+            &name_pascal,
+            &make_build_fn_name(name),
+            None,
+        ))),
+    ))
+}
+
+fn deserialize_children(children_yaml: &Yaml) -> Vec<Box<StructChild>> {
+    children_yaml
+        .as_vec()
+        .unwrap()
+        .iter()
+        .map(|child_yaml| {
+            if let Some(name) = child_yaml.as_str() {
+                deserialize_string_child(name)
+            } else {
+                let (child_name, child_props) = unwrap_single_member_hash(child_yaml);
+                deserialize_hash_child(&child_name, child_props)
+            }
+        })
+        .map(Box::new)
+        .collect()
+}
+
+pub fn deserialize_struct_spec(name: &str, struct_yaml: &Yaml) -> StructSpec {
+    let children = if struct_yaml["children"].is_array() {
+        deserialize_children(&struct_yaml["children"])
+    } else {
+        deserialize_error!("array", "children", name);
+    };
+
+    let fields = if struct_yaml["fields"].is_array() {
+        struct_yaml["fields"]
+            .as_vec()
+            .unwrap()
+            .iter()
+            .map(|field| deserialize_field(field))
+            .map(Box::new)
+            .collect()
+    } else {
+        vec![]
+    };
+
+    let derive = if struct_yaml["derive"].is_array() {
+        struct_yaml["derive"]
+            .as_vec()
+            .unwrap()
+            .iter()
+            .map(|derive| derive.as_str().unwrap().to_string())
+            .collect()
+    } else {
+        vec![]
+    };
+
+    StructSpec::new(name, children, fields, derive)
+}

ast-generator/src/deserialize/tree_enum_spec.rs

@@ -0,0 +1,56 @@
+use convert_case::{Case, Casing};
+use crate::deserialize::util::{get_as_bool_or, make_build_fn_name, unwrap_single_member_hash};
+use crate::spec::tree_enum_spec::{EnumRuleChild, EnumRuleChildKind, EnumRuleChildNodeKind, NameAndWith, TreeEnumBuildSpec, TreeEnumRule};
+use yaml_rust2::Yaml;
+
+fn deserialize_hash_enum_rule(rule: &str, props: &Yaml) -> TreeEnumRule {
+    if get_as_bool_or(&props["child"], true) {
+        let name_and_with = NameAndWith::new(
+            &rule.to_case(Case::Snake),
+            &make_build_fn_name(rule)
+        );
+        let kind = match props["kind"].as_str().unwrap() {
+            "int" => EnumRuleChildKind::Int(name_and_with),
+            "long" => EnumRuleChildKind::Long(name_and_with),
+            "double" => EnumRuleChildKind::Double(name_and_with),
+            "string" => EnumRuleChildKind::String(name_and_with),
+            "boolean" => EnumRuleChildKind::Boolean(name_and_with),
+            _ => panic!("Invalid kind: {}", props["kind"].as_str().unwrap()),
+        };
+        TreeEnumRule::new(rule, Some(Box::new(EnumRuleChild::new(Box::new(kind)))))
+    } else {
+        // no child
+        TreeEnumRule::new(rule, None)
+    }
+}
+
+fn deserialize_string_enum_rule(rule: &str) -> TreeEnumRule {
+    TreeEnumRule::new(
+        rule,
+        Some(Box::new(EnumRuleChild::new(Box::new(
+            EnumRuleChildKind::Node(EnumRuleChildNodeKind::new(
+                rule,
+                &make_build_fn_name(rule)
+            )),
+        )))),
+    )
+}
+
+pub fn deserialize_tree_enum(name: &str, props: &Yaml) -> TreeEnumBuildSpec {
+    let rules = props["rules"]
+        .as_vec()
+        .unwrap()
+        .iter()
+        .map(|rule_yaml| {
+            if let Some(rule) = rule_yaml.as_str() {
+                deserialize_string_enum_rule(rule)
+            } else {
+                let (rule, props) = unwrap_single_member_hash(rule_yaml);
+                deserialize_hash_enum_rule(&rule, props)
+            }
+        })
+        .map(Box::new)
+        .collect();
+
+    TreeEnumBuildSpec::new(name, rules)
+}

ast-generator/src/deserialize/util.rs

@@ -0,0 +1,37 @@
+use convert_case::{Case, Casing};
+use yaml_rust2::Yaml;
+
+#[macro_export]
+macro_rules! deserialize_error {
+    ($kind:expr, $key:expr, $name:expr) => {
+        panic!("Expected {} '{}' in {}.", $kind, $key, $name);
+    };
+}
+
+pub fn make_build_fn_name(s: &str) -> String {
+    format!("build_{}", s.to_case(Case::Snake))
+}
+
+pub fn make_build_pair(s: &str) -> String {
+    format!("{}_pair", s.to_case(Case::Snake))
+}
+
+pub fn unwrap_single_member_hash(hash: &Yaml) -> (String, &Yaml) {
+    let as_hash = hash.as_hash().unwrap();
+    if as_hash.is_empty() {
+        panic!("empty hash");
+    } else if as_hash.len() > 1 {
+        panic!("hash contains more than one key");
+    }
+    let (member_key, member_value) = as_hash.iter().collect::<Vec<(&Yaml, &Yaml)>>()[0];
+    let key_as_string = member_key.as_str().unwrap().to_string();
+    (key_as_string, member_value)
+}
+
+pub fn get_as_bool(yaml: &Yaml) -> bool {
+    yaml.as_bool().unwrap_or(false)
+}
+
+pub fn get_as_bool_or(yaml: &Yaml, or: bool) -> bool {
+    yaml.as_bool().unwrap_or(or)
+}

ast-generator/src/lib.rs

@@ -1,10 +1,20 @@
-mod build_fn_gen;
+mod ast_node;
+mod build_fn;
 mod deserialize;
+mod pretty_print;
 mod spec;
 mod type_gen;
+mod walk;
 
-use crate::build_fn_gen::make_struct_build_fn;
+use crate::ast_node::{
+    make_ast_enum_member, make_ast_enum_mut_member, make_ast_node_impl,
+    make_ast_node_ref_mut_unwrapper, make_ast_node_ref_unwrapper,
+};
+use crate::build_fn::make_build_fn;
+use crate::deserialize::deserialize_yaml_spec;
+use crate::pretty_print::make_pretty_print_impl;
 use crate::type_gen::make_type;
+use crate::walk::make_walk_fn;
 use proc_macro2::TokenStream;
 use quote::quote;
 use spec::BuildSpec;
@@ -14,10 +24,64 @@ fn debug_built_spec(build_spec: &BuildSpec, token_stream: &TokenStream) {
     println!("*** BuildSpec ***");
     match build_spec {
         BuildSpec::Enum(enum_build_spec) => {
-            println!("Spec name: {}", enum_build_spec.name());
+            println!("Enum Spec - build: {}", enum_build_spec.build());
+        }
+        BuildSpec::LeafEnum(leaf_enum_build_spec) => {
+            println!("Leaf Enum Spec - build: {}", leaf_enum_build_spec.build());
         }
         BuildSpec::Struct(struct_build_spec) => {
-            println!("Spec name: {}", struct_build_spec.name());
+            println!("Struct Spec - build: {}", struct_build_spec.build());
+        }
+        BuildSpec::LeafStruct(leaf_struct_build_spec) => {
+            println!(
+                "Leaf Struct Spec - build: {}",
+                leaf_struct_build_spec.build()
+            );
+        }
+        BuildSpec::Production(production_build_spec) => {
+            println!("Production Spec - name: {}", production_build_spec.name());
+        }
+        BuildSpec::NodeProduction(node_production_build_spec) => {
+            println!(
+                "Node Production Spec - name: {}",
+                node_production_build_spec.name()
+            );
+        }
+        BuildSpec::PolymorphicType(polymorphic_build_spec) => {
+            println!(
+                "Polymorphic Type Spec - name: {}",
+                polymorphic_build_spec.name()
+            );
+        }
+        BuildSpec::PolymorphicEnumLoop(polymorphic_enum_loop_build_spec) => {
+            println!(
+                "Polymorphic Enum Loop Spec - name: {}",
+                polymorphic_enum_loop_build_spec.name()
+            );
+        }
+        BuildSpec::PolymorphicPassThrough(pass_through_build_spec) => {
+            println!(
+                "Polymorphic Pass Through Spec - name: {}",
+                pass_through_build_spec.name()
+            );
+        }
+        BuildSpec::PolymorphicEnumInnerBuild(polymorphic_enum_inner_build_spec) => {
+            println!(
+                "Polymorphic Enum Inner Build Spec - name: {}",
+                polymorphic_enum_inner_build_spec.name()
+            );
+        }
+        BuildSpec::PolymorphicLeafEnum(polymorphic_leaf_enum) => {
+            println!(
+                "Polymorphic Leaf Enum Build Spec - name: {}",
+                polymorphic_leaf_enum.name()
+            );
+        }
+        BuildSpec::PolymorphicTreeEnum(polymorphic_tree_enum) => {
+            println!(
+                "Polymorphic Tree Enum Build Spec - name: {}",
+                polymorphic_tree_enum.name()
+            );
         }
     }
     println!("{:#?}", token_stream);
@@ -25,30 +89,191 @@ fn debug_built_spec(build_spec: &BuildSpec, token_stream: &TokenStream) {
     println!("{}", prettyplease::unparse(&parsed));
 }
 
-pub fn test_dump() -> String {
-    let build_specs = deserialize::deserialize_yaml_spec(include_str!("../../src/parser/ast.yaml"));
-    let mut streams: Vec<TokenStream> = vec![];
+pub struct AstGeneratedFile {
+    pub name: String,
+    pub contents: String,
+}
 
-    for build_spec in &build_specs {
-        let type_stream = make_type(build_spec);
-        debug_built_spec(build_spec, &type_stream);
-        streams.push(type_stream);
-    }
-
-    for build_spec in &build_specs {
-        match build_spec {
-            BuildSpec::Enum(_) => {}
-            BuildSpec::Struct(struct_spec) => {
-                let struct_build_fn_stream = make_struct_build_fn(struct_spec);
-                debug_built_spec(build_spec, &struct_build_fn_stream);
-                streams.push(struct_build_fn_stream);
-            }
-        }
-    }
-
-    let combined = quote! {
-        #(#streams)*
-    };
-    let file: File = syn::parse2(combined).unwrap();
+fn token_stream_to_string(token_stream: TokenStream) -> String {
+    let file: File = syn::parse2(token_stream).unwrap();
     prettyplease::unparse(&file)
 }
+
+fn generate_build_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
+    let build_fns = build_specs
+        .iter()
+        .map(|build_spec| {
+            let build_fn = make_build_fn(build_spec);
+            debug_built_spec(build_spec, &build_fn);
+            build_fn
+        })
+        .collect::<Vec<_>>();
+
+    let combined = quote! {
+        use crate::parser::Rule;
+        use pest::iterators::Pair;
+        use crate::ast::node::*;
+        use std::range::Range;
+
+        #(#build_fns)*
+    };
+
+    AstGeneratedFile {
+        name: String::from("build.rs"),
+        contents: token_stream_to_string(combined),
+    }
+}
+
+fn generate_node_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
+    let types = build_specs
+        .iter()
+        .map(|build_spec| make_type(build_spec))
+        .filter(Option::is_some)
+        .collect::<Vec<_>>();
+    let combined = quote! {
+        use std::range::Range;
+        use std::rc::Rc;
+        use std::cell::RefCell;
+        use crate::name_analysis::symbol::*;
+        use crate::type_analysis::kinds::*;
+
+        #(#types)*
+    };
+    AstGeneratedFile {
+        name: String::from("node.rs"),
+        contents: token_stream_to_string(combined),
+    }
+}
+
+fn generate_pretty_print_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
+    let impls = build_specs
+        .iter()
+        .map(|build_spec| {
+            let maybe_stream = make_pretty_print_impl(build_spec);
+            if let Some(stream) = &maybe_stream {
+                debug_built_spec(build_spec, &stream);
+            }
+            maybe_stream
+        })
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let combined = quote! {
+        use crate::ast::node::*;
+        #(#impls)*
+    };
+    AstGeneratedFile {
+        name: String::from("pretty_print.rs"),
+        contents: token_stream_to_string(combined),
+    }
+}
+
+fn generate_ast_node_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
+    let impls = build_specs
+        .iter()
+        .map(|build_spec| {
+            let maybe_stream = make_ast_node_impl(build_spec);
+            if let Some(stream) = &maybe_stream {
+                debug_built_spec(build_spec, &stream);
+            }
+            maybe_stream
+        })
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let ast_enum_members = build_specs
+        .iter()
+        .map(|build_spec| make_ast_enum_member(build_spec))
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let ast_enum_mut_members = build_specs
+        .iter()
+        .map(|build_spec| make_ast_enum_mut_member(build_spec))
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let inner_unwrappers = build_specs
+        .iter()
+        .map(|build_spec| make_ast_node_ref_unwrapper(build_spec))
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let inner_mut_unwrappers = build_specs
+        .iter()
+        .map(|build_spec| make_ast_node_ref_mut_unwrapper(build_spec))
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let combined = quote! {
+        use crate::ast::node::*;
+
+        pub enum AstNodeRef<'a> {
+            #(#ast_enum_members,)*
+        }
+
+        impl<'a> AstNodeRef<'a> {
+            pub fn inner(&self) -> &dyn AstNode<'a> {
+                match self {
+                    #(#inner_unwrappers,)*
+                }
+            }
+        }
+
+        pub enum AstNodeRefMut<'a> {
+            #(#ast_enum_mut_members,)*
+        }
+
+        impl<'a> AstNodeRefMut<'a> {
+            pub fn inner(&mut self) -> &mut dyn AstNode<'a> {
+                match self {
+                    #(#inner_mut_unwrappers,)*
+                }
+            }
+        }
+
+        pub trait AstNode<'a> {
+            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>>;
+
+            fn for_each_child_mut(&'a mut self, f: &mut dyn FnMut(&'a mut dyn AstNode<'a>));
+
+            fn as_node_ref(&'a self) -> AstNodeRef<'a>;
+
+            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a>;
+        }
+
+        #(#impls)*
+    };
+    AstGeneratedFile {
+        name: String::from("ast_node.rs"),
+        contents: token_stream_to_string(combined),
+    }
+}
+
+fn generate_walk_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
+    let stream = make_walk_fn(build_specs);
+    AstGeneratedFile {
+        name: String::from("walk.rs"),
+        contents: token_stream_to_string(stream),
+    }
+}
+
+pub fn get_build_specs(yaml: &str) -> Vec<BuildSpec> {
+    deserialize_yaml_spec(yaml)
+}
+
+pub fn generate_files(build_specs: &[BuildSpec]) -> Vec<AstGeneratedFile> {
+    vec![
+        generate_build_file(build_specs),
+        generate_node_file(build_specs),
+        generate_pretty_print_file(build_specs),
+        generate_ast_node_file(build_specs),
+        generate_walk_file(build_specs),
+    ]
+}

ast-generator/src/main.rs

@@ -1,6 +0,0 @@
-use ast_generator::test_dump;
-
-fn main() {
-    let s = test_dump();
-    println!("{}", s);
-}

ast-generator/src/pretty_print.rs

@@ -0,0 +1,347 @@
+use crate::spec::leaf_enum_spec::LeafEnumBuildSpec;
+use crate::spec::leaf_struct_spec::{LeafStructBuildSpec, LeafStructMemberKind};
+use crate::spec::polymorphic_enum_inner_build::{
+    PolymorphicEnumInnerBuild, PolymorphicEnumInnerBuildMemberKind,
+};
+use crate::spec::polymorphic_enum_loop_spec::{
+    PolymorphicEnumLoopBuildSpec, PolymorphicEnumLoopRule, PolymorphicEnumLoopRuleBuildChild,
+};
+use crate::spec::polymorphic_type_spec::PolymorphicTypeBuildSpec;
+use crate::spec::struct_spec::{MemberChildBuild, StructChild, StructSpec, VecChildBuild};
+use crate::spec::tree_enum_spec::{EnumRuleChildKind, TreeEnumBuildSpec};
+use crate::spec::BuildSpec;
+use convert_case::{Case, Casing};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+fn make_result() -> TokenStream {
+    quote! { std::fmt::Result }
+}
+
+fn make_polymorphic_enum_inner_build_p2_impl(spec: &PolymorphicEnumInnerBuild) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.name());
+    let result = make_result();
+
+    let type_string = spec.name();
+
+    let child_matchers = spec
+        .members()
+        .map(|member| {
+            let variant_ident = format_ident!("{}", member.name());
+            match member.kind() {
+                PolymorphicEnumInnerBuildMemberKind::Leaf => {
+                    let variant_string = member.name();
+                    quote! {
+                        #type_ident::#variant_ident => writer.writeln_indented(#variant_string)?
+                    }
+                }
+                PolymorphicEnumInnerBuildMemberKind::Struct => {
+                    let child_ident = format_ident!("{}", member.name().to_case(Case::Snake));
+                    quote! {
+                        #type_ident::#variant_ident(#child_ident) => {
+                            #child_ident.pretty_print(writer)?;
+                        }
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        impl PrettyPrint for #type_ident {
+            fn pretty_print(&self, writer: &mut IndentWriter) -> #result {
+                writer.writeln_indented(#type_string)?;
+                writer.increase_indent();
+                match self {
+                    #(#child_matchers,)*
+                    _ => {}
+                }
+                writer.decrease_indent();
+                Ok(())
+            }
+        }
+    }
+}
+
+fn make_polymorphic_enum_loop_p2_impl(spec: &PolymorphicEnumLoopBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.name());
+    let type_string = spec.name();
+
+    let build = spec
+        .rules()
+        .find(|rule| match rule {
+            PolymorphicEnumLoopRule::Build(_) => true,
+            _ => false,
+        })
+        .map(|rule| match rule {
+            PolymorphicEnumLoopRule::Build(build) => build,
+            _ => unreachable!(),
+        })
+        .unwrap();
+
+    let child_print_statements = build
+        .children()
+        .filter(|child| match child {
+            PolymorphicEnumLoopRuleBuildChild::Special(_) => false,
+            _ => true,
+        })
+        .map(|child| {
+            let child_ident = match child {
+                PolymorphicEnumLoopRuleBuildChild::UseCurrent(use_current) => {
+                    format_ident!("{}", use_current.name())
+                }
+                PolymorphicEnumLoopRuleBuildChild::OnEach(on_each) => {
+                    format_ident!("{}", on_each.name())
+                }
+                _ => unreachable!(),
+            };
+            quote! {
+                self.#child_ident().pretty_print(writer)?;
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let result = make_result();
+
+    quote! {
+        impl PrettyPrint for #type_ident {
+            fn pretty_print(&self, writer: &mut IndentWriter) -> #result {
+                writer.writeln_indented(#type_string)?;
+                writer.increase_indent();
+                #(#child_print_statements)*
+                writer.decrease_indent();
+                Ok(())
+            }
+        }
+    }
+}
+
+fn make_polymorphic_type_p2_impl(spec: &PolymorphicTypeBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.name());
+    let child_matchers = spec
+        .variants()
+        .map(|member| {
+            let enum_member_ident = format_ident!("{}", member.name());
+            let inner_name = format_ident!("{}", member.inner_kind().to_case(Case::Snake));
+            quote! {
+                #type_ident::#enum_member_ident(#inner_name) => #inner_name.pretty_print(writer)
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let result = make_result();
+
+    quote! {
+        impl PrettyPrint for #type_ident {
+            fn pretty_print(&self, writer: &mut IndentWriter) -> #result {
+                match self {
+                    #(#child_matchers,)*
+                }
+            }
+        }
+    }
+}
+
+fn make_leaf_enum_p2_impl(spec: &LeafEnumBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.build());
+    let child_matchers = spec
+        .rules()
+        .map(|rule| {
+            let enum_variant_ident = format_ident!("{}", rule);
+            let name_str = rule;
+            quote! {
+                #type_ident::#enum_variant_ident => writer.writeln_indented(#name_str)
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let result = make_result();
+
+    quote! {
+        impl PrettyPrint for #type_ident {
+            fn pretty_print(&self, writer: &mut IndentWriter) -> #result {
+                match self {
+                    #(#child_matchers,)*
+                }
+            }
+        }
+    }
+}
+
+fn make_tree_enum_p2_impl(spec: &TreeEnumBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.build());
+    let type_str = spec.build();
+
+    let child_matchers = spec
+        .rules()
+        .map(|rule| {
+            let enum_variant_ident = format_ident!("{}", rule.rule());
+            if let Some(child) = rule.child() {
+                match child.kind() {
+                    EnumRuleChildKind::Node(node_child) => {
+                        let child_name_ident =
+                            format_ident!("{}", node_child.node_kind().to_case(Case::Snake));
+                        Some(quote! {
+                            #type_ident::#enum_variant_ident(#child_name_ident) => {
+                                #child_name_ident.pretty_print(writer)?;
+                            }
+                        })
+                    }
+                    _ => None,
+                }
+            } else {
+                let variant_str = rule.rule();
+                Some(quote! {
+                    #type_ident::#enum_variant_ident => writer.writeln_indented(#variant_str)?
+                })
+            }
+        })
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let result = make_result();
+
+    quote! {
+        impl PrettyPrint for #type_ident {
+            fn pretty_print(&self, writer: &mut IndentWriter) -> #result {
+                writer.writeln_indented(#type_str)?;
+                writer.increase_indent();
+                match self {
+                    #(#child_matchers,)*
+                    _ => {}
+                }
+                writer.decrease_indent();
+                Ok(())
+            }
+        }
+    }
+}
+
+fn make_leaf_struct_p2_impl(leaf_struct_build_spec: &LeafStructBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", leaf_struct_build_spec.build());
+    let member_formatters = leaf_struct_build_spec
+        .members()
+        .map(|member| match member.kind() {
+            LeafStructMemberKind::String => Some("{}"),
+            LeafStructMemberKind::FileId => None,
+            LeafStructMemberKind::Range => None,
+        })
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>()
+        .join(", ");
+
+    let format_string = format!("{}({})", leaf_struct_build_spec.build(), member_formatters);
+
+    let members = leaf_struct_build_spec
+        .members()
+        .map(|member| match member.kind() {
+            LeafStructMemberKind::String => {
+                let member_ident = format_ident!("{}", member.name());
+                Some(quote! {
+                    self.#member_ident()
+                })
+            }
+            _ => None,
+        })
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let result = make_result();
+
+    quote! {
+        impl PrettyPrint for #type_ident {
+            fn pretty_print(&self, writer: &mut IndentWriter) -> #result {
+                writer.writeln_indented(&format!(#format_string, #(#members),*))
+            }
+        }
+    }
+}
+
+fn make_struct_p2_impl(struct_build_spec: &StructSpec) -> TokenStream {
+    let child_print_statements = struct_build_spec
+        .children()
+        .map(|child| match child {
+            StructChild::SkipChild(_) => None,
+            StructChild::VecChild(vec_child) => match vec_child.build() {
+                VecChildBuild::Node(_) => {
+                    let child_ident = format_ident!("{}", vec_child.name());
+                    Some(quote! {
+                        for child in self.#child_ident() {
+                            child.pretty_print(writer)?;
+                        }
+                    })
+                }
+                VecChildBuild::String(_) => None,
+            },
+            StructChild::MemberChild(member_child) => match member_child.build() {
+                MemberChildBuild::Node(_) => {
+                    let child_ident = format_ident!("{}", member_child.name());
+                    if member_child.optional() {
+                        Some(quote! {
+                            if let Some(child) = self.#child_ident() {
+                                child.pretty_print(writer)?;
+                            }
+                        })
+                    } else {
+                        Some(quote! {
+                            self.#child_ident().pretty_print(writer)?;
+                        })
+                    }
+                }
+                MemberChildBuild::Boolean(_) => {
+                    let format_string = format!("{}({})", member_child.name(), "{}");
+                    let child_ident = format_ident!("{}", member_child.name());
+                    Some(quote! {
+                        writer.writeln_indented(&format!(#format_string, self.#child_ident()))?;
+                    })
+                }
+            },
+            StructChild::Special(_) => None,
+        })
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let type_ident = format_ident!("{}", struct_build_spec.build());
+    let type_string = struct_build_spec.build();
+
+    let result = make_result();
+
+    quote! {
+        impl PrettyPrint for #type_ident {
+            fn pretty_print(&self, writer: &mut IndentWriter) -> #result {
+                writer.writeln_indented(#type_string)?;
+                writer.increase_indent();
+                #(#child_print_statements)*
+                writer.decrease_indent();
+                Ok(())
+            }
+        }
+    }
+}
+
+pub fn make_pretty_print_impl(build_spec: &BuildSpec) -> Option<TokenStream> {
+    match build_spec {
+        BuildSpec::Struct(struct_spec) => Some(make_struct_p2_impl(struct_spec)),
+        BuildSpec::LeafStruct(leaf_struct) => Some(make_leaf_struct_p2_impl(leaf_struct)),
+        BuildSpec::Enum(enum_spec) => Some(make_tree_enum_p2_impl(enum_spec)),
+        BuildSpec::LeafEnum(leaf_enum) => Some(make_leaf_enum_p2_impl(leaf_enum)),
+        BuildSpec::Production(_) => None,
+        BuildSpec::NodeProduction(_) => None,
+        BuildSpec::PolymorphicType(polymorphic_type) => {
+            Some(make_polymorphic_type_p2_impl(polymorphic_type))
+        }
+        BuildSpec::PolymorphicPassThrough(_) => None,
+        BuildSpec::PolymorphicEnumLoop(polymorphic_enum_loop) => {
+            Some(make_polymorphic_enum_loop_p2_impl(polymorphic_enum_loop))
+        }
+        BuildSpec::PolymorphicEnumInnerBuild(polymorphic_enum_inner_build) => Some(
+            make_polymorphic_enum_inner_build_p2_impl(polymorphic_enum_inner_build),
+        ),
+        BuildSpec::PolymorphicLeafEnum(_) => None,
+        BuildSpec::PolymorphicTreeEnum(_) => None,
+    }
+}

ast-generator/src/spec.rs

@@ -1,328 +0,0 @@
-use crate::build_fn_gen::make_build_fn_name;
-use convert_case::{Case, Casing};
-
-pub enum BuildSpec {
-    Enum(EnumBuildSpec),
-    Struct(StructBuildSpec),
-}
-
-pub struct EnumBuildSpec {
-    name: String,
-    build: String,
-    rules: Vec<EnumRule>,
-}
-
-impl EnumBuildSpec {
-    pub fn from_name(name: &str, rules: Vec<EnumRule>) -> Self {
-        EnumBuildSpec {
-            name: name.to_string(),
-            build: name.to_string(),
-            rules,
-        }
-    }
-
-    /// The top-level key for the build spec in the yaml file.
-    pub fn name(&self) -> &str {
-        &self.name
-    }
-
-    /// The enum type to be built, in Pascal case.
-    pub fn build(&self) -> &str {
-        &self.build
-    }
-
-    /// The individual rule specs.
-    pub fn rules(&self) -> &[EnumRule] {
-        &self.rules
-    }
-}
-
-pub struct EnumRule {
-    rule: String,
-    build: String,
-    with: String,
-}
-
-impl EnumRule {
-    pub fn from_rule(rule: &str) -> Self {
-        Self {
-            rule: rule.to_string(),
-            build: rule.to_string(),
-            with: make_build_fn_name(rule),
-        }
-    }
-
-    pub fn new(rule: &str, build: &str, with: &str) -> Self {
-        Self {
-            rule: rule.to_string(),
-            build: build.to_string(),
-            with: with.to_string(),
-        }
-    }
-
-    /// The enum rule to match, in Pascal case.
-    pub fn rule(&self) -> &str {
-        &self.rule
-    }
-
-    /// The type to build, in Pascal case.
-    pub fn build(&self) -> &str {
-        &self.build
-    }
-
-    /// The build-fn name, in snake case.
-    pub fn with(&self) -> &str {
-        &self.with
-    }
-}
-
-pub struct StructBuildSpec {
-    name: String,
-    build: String,
-    var_name: String,
-    with: String,
-    children: Vec<ChildSpec>,
-}
-
-impl StructBuildSpec {
-    pub fn from_name(name: &str, child_specs: Vec<ChildSpec>) -> Self {
-        Self {
-            name: name.to_string(),
-            build: name.to_string(),
-            var_name: name.to_case(Case::Snake),
-            with: make_build_fn_name(name),
-            children: child_specs,
-        }
-    }
-
-    /// The top-level name of this build spec.
-    pub fn name(&self) -> &str {
-        &self.name
-    }
-
-    /// The type to be built, in Pascal case.
-    pub fn build(&self) -> &str {
-        &self.build
-    }
-
-    /// The name of the variable to be built, in snake case.
-    pub fn var_name(&self) -> &str {
-        &self.var_name
-    }
-
-    /// The build-fn name, in snake case.
-    pub fn with(&self) -> &str {
-        &self.with
-    }
-
-    /// The children for this build spec.
-    pub fn children(&self) -> &[ChildSpec] {
-        &self.children
-    }
-}
-
-pub enum ChildSpec {
-    SkipChild(SkipChild),
-    VecChild(VecChild),
-    SingleChild(SingleChild),
-}
-
-pub struct SkipChild {
-    name: String,
-    rule: String,
-}
-
-impl SkipChild {
-    pub fn new(name: &str, rule: &str) -> Self {
-        Self {
-            name: name.to_string(),
-            rule: rule.to_string(),
-        }
-    }
-
-    /// The name of this child spec.
-    pub fn name(&self) -> &str {
-        &self.name
-    }
-
-    /// The grammar rule to match.
-    pub fn rule(&self) -> &str {
-        &self.rule
-    }
-}
-
-pub struct VecChild {
-    name: String,
-    rule: String,
-    build: VecChildToBuild,
-}
-
-impl VecChild {
-    pub fn new(name: &str, rule: &str, build: VecChildToBuild) -> Self {
-        Self {
-            name: name.to_string(),
-            rule: rule.to_string(),
-            build,
-        }
-    }
-
-    /// The name of this child.
-    pub fn name(&self) -> &str {
-        &self.name
-    }
-
-    /// The rule to match to build this child.
-    pub fn rule(&self) -> &str {
-        &self.rule
-    }
-
-    /// The build info for this child.
-    pub fn build(&self) -> &VecChildToBuild {
-        &self.build
-    }
-}
-
-#[derive(Debug)]
-pub enum VecChildToBuild {
-    Type(VecTypeChildToBuild),
-}
-
-#[derive(Debug)]
-pub struct VecTypeChildToBuild {
-    build: String,
-    var_name: String,
-    with: String,
-}
-
-impl VecTypeChildToBuild {
-    pub fn new(build: &str, var_name: &str, with: &str) -> Self {
-        Self {
-            build: build.to_string(),
-            var_name: var_name.to_string(),
-            with: with.to_string(),
-        }
-    }
-
-    /// The type to build, in Pascal case.
-    pub fn build(&self) -> &str {
-        &self.build
-    }
-
-    /// The name of the variable to build, in snake case.
-    pub fn var_name(&self) -> &str {
-        &self.var_name
-    }
-
-    /// The build-fn name.
-    pub fn with(&self) -> &str {
-        &self.with
-    }
-}
-
-#[derive(Debug)]
-pub struct SingleChild {
-    name: String,
-    rule: String,
-    build: SingleChildToBuild,
-}
-
-impl SingleChild {
-    pub fn from_name_snake(name: &str) -> Self {
-        Self {
-            name: name.to_string(),
-            rule: name.to_case(Case::Pascal),
-            build: SingleChildToBuild::Type(SingleTypeChildToBuild::from_build_or_rule(
-                &name.to_case(Case::Pascal),
-            )),
-        }
-    }
-
-    pub fn new(name: &str, rule: &str, build: SingleChildToBuild) -> Self {
-        Self {
-            name: name.to_string(),
-            rule: rule.to_string(),
-            build,
-        }
-    }
-
-    /// The name of this child in the yaml file, in snake case.
-    pub fn name(&self) -> &str {
-        &self.name
-    }
-
-    /// The grammar rule to match to build this child.
-    pub fn rule(&self) -> &str {
-        &self.rule
-    }
-
-    /// The specification for what to actually build.
-    pub fn build(&self) -> &SingleChildToBuild {
-        &self.build
-    }
-}
-
-#[derive(Debug)]
-pub enum SingleChildToBuild {
-    Type(SingleTypeChildToBuild),
-    Boolean(SingleBooleanChildToBuild),
-}
-
-#[derive(Debug)]
-pub struct SingleTypeChildToBuild {
-    build: String,
-    var_name: String,
-    with: String,
-}
-
-impl SingleTypeChildToBuild {
-    pub fn from_build_or_rule(build_or_rule: &str) -> Self {
-        Self {
-            build: build_or_rule.to_string(),
-            var_name: build_or_rule.to_case(Case::Snake),
-            with: make_build_fn_name(build_or_rule),
-        }
-    }
-
-    /// The type to build, in Pascal case.
-    pub fn build(&self) -> &str {
-        &self.build
-    }
-
-    /// The variable name to build, in snake case.
-    pub fn var_name(&self) -> &str {
-        &self.var_name
-    }
-
-    /// The build-fn name.
-    pub fn with(&self) -> &str {
-        &self.with
-    }
-}
-
-#[derive(Debug)]
-pub struct SingleBooleanChildToBuild {
-    var_name: String,
-    on: BuildBooleanOn,
-}
-
-impl SingleBooleanChildToBuild {
-    pub fn new(var_name: &str, on: BuildBooleanOn) -> Self {
-        Self {
-            var_name: var_name.to_string(),
-            on,
-        }
-    }
-
-    pub fn var_name(&self) -> &str {
-        &self.var_name
-    }
-
-    pub fn on(&self) -> &BuildBooleanOn {
-        &self.on
-    }
-}
-
-#[derive(Debug)]
-pub enum BuildBooleanOn {
-    RulePresent,
-}

ast-generator/src/spec/leaf_enum_spec.rs

@@ -0,0 +1,21 @@
+pub struct LeafEnumBuildSpec {
+    build: String,
+    rules: Vec<String>,
+}
+
+impl LeafEnumBuildSpec {
+    pub fn new(build: &str, rules: Vec<String>) -> Self {
+        Self {
+            build: build.to_string(),
+            rules,
+        }
+    }
+
+    pub fn build(&self) -> &str {
+        &self.build
+    }
+
+    pub fn rules(&self) -> impl Iterator<Item = &str> {
+        self.rules.iter().map(AsRef::as_ref)
+    }
+}

ast-generator/src/spec/leaf_struct_spec.rs

@@ -0,0 +1,55 @@
+pub struct LeafStructBuildSpec {
+    build: String,
+    members: Vec<Box<LeafStructMember>>,
+    derive: Vec<String>,
+}
+
+impl LeafStructBuildSpec {
+    pub fn new(build: &str, members: Vec<Box<LeafStructMember>>, derive: Vec<String>) -> Self {
+        Self {
+            build: build.to_string(),
+            members,
+            derive,
+        }
+    }
+
+    pub fn build(&self) -> &str {
+        &self.build
+    }
+
+    pub fn members(&self) -> impl Iterator<Item = &LeafStructMember> {
+        self.members.iter().map(Box::as_ref)
+    }
+    
+    pub fn derive(&self) -> impl Iterator<Item = &str> {
+        self.derive.iter().map(String::as_str)
+    }
+}
+
+pub struct LeafStructMember {
+    name: String,
+    kind: LeafStructMemberKind,
+}
+
+impl LeafStructMember {
+    pub fn new(name: &str, kind: LeafStructMemberKind) -> Self {
+        Self {
+            name: name.to_string(),
+            kind,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> &LeafStructMemberKind {
+        &self.kind
+    }
+}
+
+pub enum LeafStructMemberKind {
+    String,
+    FileId,
+    Range
+}

ast-generator/src/spec/mod.rs

@@ -0,0 +1,109 @@
+use leaf_enum_spec::LeafEnumBuildSpec;
+use leaf_struct_spec::LeafStructBuildSpec;
+use node_production_spec::NodeProductionBuildSpec;
+use polymorphic_enum_inner_build::PolymorphicEnumInnerBuild;
+use polymorphic_enum_loop_spec::PolymorphicEnumLoopBuildSpec;
+use polymorphic_leaf_enum::PolymorphicLeafEnum;
+use polymorphic_pass_through_spec::PolymorphicPassThroughBuildSpec;
+use polymorphic_tree_enum_spec::PolymorphicTreeEnumSpec;
+use polymorphic_type_spec::PolymorphicTypeBuildSpec;
+use production_spec::ProductionBuildSpec;
+use struct_spec::StructSpec;
+use tree_enum_spec::TreeEnumBuildSpec;
+
+pub(crate) mod leaf_enum_spec;
+pub(crate) mod leaf_struct_spec;
+pub(crate) mod node_production_spec;
+pub(crate) mod polymorphic_enum_inner_build;
+pub(crate) mod polymorphic_enum_loop_spec;
+pub(crate) mod polymorphic_leaf_enum;
+pub(crate) mod polymorphic_pass_through_spec;
+pub(crate) mod polymorphic_tree_enum_spec;
+pub(crate) mod polymorphic_type_spec;
+pub(crate) mod production_spec;
+pub(crate) mod struct_spec;
+pub(crate) mod tree_enum_spec;
+
+pub enum BuildSpec {
+    Enum(TreeEnumBuildSpec),
+    LeafEnum(LeafEnumBuildSpec),
+    Struct(StructSpec),
+    LeafStruct(LeafStructBuildSpec),
+    Production(ProductionBuildSpec),
+    NodeProduction(NodeProductionBuildSpec),
+    PolymorphicType(PolymorphicTypeBuildSpec),
+    PolymorphicEnumLoop(PolymorphicEnumLoopBuildSpec),
+    PolymorphicPassThrough(PolymorphicPassThroughBuildSpec),
+    PolymorphicEnumInnerBuild(PolymorphicEnumInnerBuild),
+    PolymorphicLeafEnum(PolymorphicLeafEnum),
+    PolymorphicTreeEnum(PolymorphicTreeEnumSpec),
+}
+
+#[derive(Debug)]
+pub struct SpecialChild {
+    name: String,
+    kind: SpecialChildKind,
+}
+
+impl SpecialChild {
+    pub fn new(name: &str, kind: SpecialChildKind) -> Self {
+        Self {
+            name: name.to_string(),
+            kind,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> &SpecialChildKind {
+        &self.kind
+    }
+}
+
+#[derive(Debug)]
+pub enum SpecialChildKind {
+    FileId,
+    Range,
+}
+
+#[derive(Debug)]
+pub struct StructField {
+    name: String,
+    kind: String,
+    wrap: Option<StructFieldWrap>,
+    vec: bool,
+}
+
+impl StructField {
+    pub fn new(name: &str, kind: &str, wrap: Option<StructFieldWrap>, vec: bool) -> Self {
+        Self {
+            name: name.to_string(),
+            kind: kind.to_string(),
+            wrap,
+            vec,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+
+    pub fn wrap(&self) -> Option<&StructFieldWrap> {
+        self.wrap.as_ref()
+    }
+
+    pub fn vec(&self) -> bool {
+        self.vec
+    }
+}
+
+#[derive(Debug)]
+pub enum StructFieldWrap {
+    RcRefCell,
+}

ast-generator/src/spec/node_production_spec.rs

@@ -0,0 +1,27 @@
+pub struct NodeProductionBuildSpec {
+    name: String,
+    kind: String,
+    with: String
+}
+
+impl NodeProductionBuildSpec {
+    pub fn new(name: &str, kind: &str, with: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            kind: kind.to_string(),
+            with: with.to_string()
+        }
+    }
+    
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+    
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+    
+    pub fn with(&self) -> &str {
+        &self.with
+    }
+}

ast-generator/src/spec/polymorphic_enum_inner_build.rs

@@ -0,0 +1,76 @@
+pub struct PolymorphicEnumInnerBuild {
+    name: String,
+    members: Vec<PolymorphicEnumInnerBuildMember>,
+    rules: Vec<PolymorphicEnumInnerBuildRule>,
+}
+
+impl PolymorphicEnumInnerBuild {
+    pub fn new(name: &str, members: Vec<PolymorphicEnumInnerBuildMember>, rules: Vec<PolymorphicEnumInnerBuildRule>) -> Self {
+        Self {
+            name: name.to_string(),
+            members,
+            rules,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn members(&self) -> impl Iterator<Item = &PolymorphicEnumInnerBuildMember> {
+        self.members.iter()
+    }
+
+    pub fn rules(&self) -> impl Iterator<Item = &PolymorphicEnumInnerBuildRule> {
+        self.rules.iter()
+    }
+}
+
+pub struct PolymorphicEnumInnerBuildMember {
+    name: String,
+    kind: PolymorphicEnumInnerBuildMemberKind
+}
+
+impl PolymorphicEnumInnerBuildMember {
+    pub fn new(name: &str, kind: PolymorphicEnumInnerBuildMemberKind) -> Self {
+        Self {
+            name: name.to_string(),
+            kind
+        }
+    }
+    
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+    
+    pub fn kind(&self) -> &PolymorphicEnumInnerBuildMemberKind {
+        &self.kind
+    }
+}
+
+pub enum PolymorphicEnumInnerBuildMemberKind {
+    Leaf,
+    Struct
+}
+
+pub struct PolymorphicEnumInnerBuildRule {
+    name: String,
+    with: String,
+}
+
+impl PolymorphicEnumInnerBuildRule {
+    pub fn new(name: &str, with: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            with: with.to_string(),
+        }
+    }
+    
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+    
+    pub fn with(&self) -> &str {
+        &self.with
+    }
+}

ast-generator/src/spec/polymorphic_enum_loop_spec.rs

@@ -0,0 +1,162 @@
+use crate::spec::{SpecialChild, StructField};
+
+pub struct PolymorphicEnumLoopBuildSpec {
+    name: String,
+    kind: String,
+    reverse: bool,
+    rules: Vec<Box<PolymorphicEnumLoopRule>>,
+}
+
+impl PolymorphicEnumLoopBuildSpec {
+    pub fn new(
+        name: &str,
+        kind: &str,
+        reverse: bool,
+        rules: Vec<Box<PolymorphicEnumLoopRule>>,
+    ) -> Self {
+        Self {
+            name: name.to_string(),
+            kind: kind.to_string(),
+            reverse,
+            rules,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+
+    pub fn reverse(&self) -> bool {
+        self.reverse
+    }
+
+    pub fn rules(&self) -> impl Iterator<Item = &PolymorphicEnumLoopRule> {
+        self.rules.iter().map(Box::as_ref)
+    }
+}
+
+pub enum PolymorphicEnumLoopRule {
+    PassThrough(PolymorphicEnumLoopRulePassThrough),
+    Build(PolymorphicEnumLoopRuleBuild),
+}
+
+pub struct PolymorphicEnumLoopRulePassThrough {
+    name: String,
+    kind: String,
+    with: String,
+}
+
+impl PolymorphicEnumLoopRulePassThrough {
+    pub fn new(name: &str, kind: &str, with: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            kind: kind.to_string(),
+            with: with.to_string(),
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+
+    pub fn with(&self) -> &str {
+        &self.with
+    }
+}
+
+pub struct PolymorphicEnumLoopRuleBuild {
+    name: String,
+    variant: String,
+    children: Vec<Box<PolymorphicEnumLoopRuleBuildChild>>,
+    fields: Vec<StructField>,
+}
+
+impl PolymorphicEnumLoopRuleBuild {
+    pub fn new(
+        name: &str,
+        variant: &str,
+        children: Vec<Box<PolymorphicEnumLoopRuleBuildChild>>,
+        fields: Vec<StructField>,
+    ) -> Self {
+        Self {
+            name: name.to_string(),
+            variant: variant.to_string(),
+            children,
+            fields,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn variant(&self) -> &str {
+        &self.variant
+    }
+
+    pub fn children(&self) -> impl Iterator<Item = &PolymorphicEnumLoopRuleBuildChild> {
+        self.children.iter().map(Box::as_ref)
+    }
+    
+    pub fn fields(&self) -> &[StructField] {
+        &self.fields
+    }
+}
+
+pub enum PolymorphicEnumLoopRuleBuildChild {
+    UseCurrent(PolymorphicEnumLoopChildUseCurrent),
+    OnEach(PolymorphicEnumLoopRuleChildOnEach),
+    Special(SpecialChild),
+}
+
+pub struct PolymorphicEnumLoopChildUseCurrent {
+    name: String,
+    kind: String,
+}
+
+impl PolymorphicEnumLoopChildUseCurrent {
+    pub fn new(name: &str, kind: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            kind: kind.to_string(),
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+}
+
+pub struct PolymorphicEnumLoopRuleChildOnEach {
+    name: String,
+    rule: String,
+}
+
+impl PolymorphicEnumLoopRuleChildOnEach {
+    pub fn new(name: &str, rule: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            rule: rule.to_string(),
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn rule(&self) -> &str {
+        &self.rule
+    }
+}

ast-generator/src/spec/polymorphic_leaf_enum.rs

@@ -0,0 +1,27 @@
+pub struct PolymorphicLeafEnum {
+    name: String,
+    kind: String,
+    rules: Vec<String>,
+}
+
+impl PolymorphicLeafEnum {
+    pub fn new(name: &str, kind: &str, rules: Vec<String>) -> Self {
+        Self {
+            name: name.to_string(),
+            kind: kind.to_string(),
+            rules,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+
+    pub fn rules(&self) -> impl Iterator<Item = &str> {
+        self.rules.iter().map(AsRef::as_ref)
+    }
+}

ast-generator/src/spec/polymorphic_pass_through_spec.rs

@@ -0,0 +1,36 @@
+pub struct PolymorphicPassThroughBuildSpec {
+    name: String,
+    build_kind: String,
+    variants: Vec<Box<PolymorphicPassThroughVariant>>,
+}
+
+impl PolymorphicPassThroughBuildSpec {
+    pub fn new(
+        name: &str,
+        build_kind: &str,
+        variants: Vec<Box<PolymorphicPassThroughVariant>>,
+    ) -> Self {
+        Self {
+            name: name.to_string(),
+            build_kind: build_kind.to_string(),
+            variants,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn build_kind(&self) -> &str {
+        &self.build_kind
+    }
+
+    pub fn variants(&self) -> impl Iterator<Item = &PolymorphicPassThroughVariant> {
+        self.variants.iter().map(Box::as_ref)
+    }
+}
+
+pub enum PolymorphicPassThroughVariant {
+    Inner { name: String, kind: String },
+    PassThrough { name: String, kind: String },
+}

ast-generator/src/spec/polymorphic_tree_enum_spec.rs

@@ -0,0 +1,27 @@
+pub struct PolymorphicTreeEnumSpec {
+    name: String,
+    kind: String,
+    rules: Vec<String>,
+}
+
+impl PolymorphicTreeEnumSpec {
+    pub fn new(name: &str, kind: &str, rules: &[&str]) -> Self {
+        Self {
+            name: name.to_string(),
+            kind: kind.to_string(),
+            rules: rules.iter().map(ToString::to_string).collect(),
+        }
+    }
+    
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+    
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+    
+    pub fn rules(&self) -> impl Iterator<Item = &str> {
+        self.rules.iter().map(AsRef::as_ref)
+    }
+}

ast-generator/src/spec/polymorphic_type_spec.rs

@@ -0,0 +1,49 @@
+pub struct PolymorphicTypeBuildSpec {
+    name: String,
+    variants: Vec<Box<PolymorphicTypeVariant>>,
+    kind: String,
+}
+
+impl PolymorphicTypeBuildSpec {
+    pub fn new(name: &str, variants: Vec<Box<PolymorphicTypeVariant>>, kind: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            variants,
+            kind: kind.to_string(),
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn variants(&self) -> impl Iterator<Item = &PolymorphicTypeVariant> {
+        self.variants.iter().map(Box::as_ref)
+    }
+
+    pub fn kind(&self) -> &str {
+        self.kind.as_str()
+    }
+}
+
+pub struct PolymorphicTypeVariant {
+    name: String,
+    inner_kind: String,
+}
+
+impl PolymorphicTypeVariant {
+    pub fn new(name: &str, inner_kind: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            inner_kind: inner_kind.to_string(),
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn inner_kind(&self) -> &str {
+        &self.inner_kind
+    }
+}

ast-generator/src/spec/production_spec.rs

@@ -0,0 +1,38 @@
+pub struct ProductionBuildSpec {
+    name: String,
+    kind: ProductionKind,
+}
+
+impl ProductionBuildSpec {
+    pub fn new(name: &str, kind: ProductionKind) -> Self {
+        Self {
+            name: name.to_string(),
+            kind,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> &ProductionKind {
+        &self.kind
+    }
+}
+
+pub enum ProductionKind {
+    Int,
+    Long,
+    Double,
+    String(ProductionStringFrom),
+    Boolean(ProductionBooleanFrom),
+}
+
+pub enum ProductionStringFrom {
+    StringInner,
+    WholePair,
+}
+
+pub enum ProductionBooleanFrom {
+    ParseWholePair,
+}

ast-generator/src/spec/struct_spec.rs

@@ -0,0 +1,250 @@
+use crate::spec::{SpecialChild, StructField};
+
+pub struct StructSpec {
+    build: String,
+    children: Vec<Box<StructChild>>,
+    fields: Vec<Box<StructField>>,
+    derive: Vec<String>,
+}
+
+impl StructSpec {
+    pub fn new(
+        build: &str,
+        children: Vec<Box<StructChild>>,
+        fields: Vec<Box<StructField>>,
+        derive: Vec<String>,
+    ) -> Self {
+        Self {
+            build: build.to_string(),
+            children,
+            fields,
+            derive,
+        }
+    }
+
+    /// The type to be built, in Pascal case.
+    pub fn build(&self) -> &str {
+        &self.build
+    }
+
+    /// The children for this build spec.
+    pub fn children(&self) -> impl Iterator<Item = &StructChild> {
+        self.children.iter().map(Box::as_ref)
+    }
+
+    pub fn fields(&self) -> impl Iterator<Item = &StructField> {
+        self.fields.iter().map(Box::as_ref)
+    }
+
+    pub fn derive(&self) -> &[String] {
+        &self.derive
+    }
+}
+
+pub enum StructChild {
+    SkipChild(SkipChild),
+    VecChild(VecChild),
+    MemberChild(MemberChild),
+    Special(SpecialChild),
+}
+
+impl StructChild {
+    pub fn is_special(&self) -> bool {
+        match self {
+            StructChild::Special(_) => true,
+            _ => false,
+        }
+    }
+
+    pub fn unwrap_special(&self) -> Option<&SpecialChild> {
+        match self {
+            StructChild::Special(special_child) => Some(special_child),
+            _ => None,
+        }
+    }
+}
+
+pub struct SkipChild {
+    rule: String,
+}
+
+impl SkipChild {
+    pub fn new(rule: &str) -> Self {
+        Self {
+            rule: rule.to_string(),
+        }
+    }
+
+    /// The grammar rule to match.
+    pub fn rule(&self) -> &str {
+        &self.rule
+    }
+}
+
+pub struct VecChild {
+    name: String,
+    rule: String,
+    build: Box<VecChildBuild>,
+}
+
+impl VecChild {
+    pub fn new(name: &str, rule: &str, build: Box<VecChildBuild>) -> Self {
+        Self {
+            name: name.to_string(),
+            rule: rule.to_string(),
+            build,
+        }
+    }
+
+    /// The name of this child.
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    /// The rule to match to build this child.
+    pub fn rule(&self) -> &str {
+        &self.rule
+    }
+
+    pub fn build(&self) -> &VecChildBuild {
+        &self.build
+    }
+}
+
+pub enum VecChildBuild {
+    String(VecChildStringBuild),
+    Node(VecChildNodeBuild),
+}
+
+pub struct VecChildStringBuild {
+    with: String,
+}
+
+impl VecChildStringBuild {
+    pub fn new(with: &str) -> Self {
+        Self {
+            with: with.to_string(),
+        }
+    }
+
+    pub fn with(&self) -> &str {
+        &self.with
+    }
+}
+
+pub struct VecChildNodeBuild {
+    kind: String,
+    with: String,
+}
+
+impl VecChildNodeBuild {
+    pub fn new(kind: &str, with: &str) -> Self {
+        Self {
+            kind: kind.to_string(),
+            with: with.to_string(),
+        }
+    }
+
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+
+    pub fn with(&self) -> &str {
+        &self.with
+    }
+}
+
+#[derive(Debug)]
+pub struct MemberChild {
+    name: String,
+    rule: String,
+    optional: bool,
+    build: Box<MemberChildBuild>,
+}
+
+impl MemberChild {
+    pub fn new(name: &str, rule: &str, optional: bool, build: Box<MemberChildBuild>) -> Self {
+        Self {
+            name: name.to_string(),
+            rule: rule.to_string(),
+            optional,
+            build,
+        }
+    }
+
+    /// The name of this child in the yaml file, in snake case.
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    /// The grammar rule to match to build this child.
+    pub fn rule(&self) -> &str {
+        &self.rule
+    }
+
+    pub fn optional(&self) -> bool {
+        self.optional
+    }
+
+    /// The specification for what to actually build.
+    pub fn build(&self) -> &MemberChildBuild {
+        &self.build
+    }
+}
+
+#[derive(Debug)]
+pub enum MemberChildBuild {
+    Node(NodeMemberBuild),
+    Boolean(BooleanMemberBuild),
+}
+
+#[derive(Debug)]
+pub struct NodeMemberBuild {
+    kind: String,
+    with: String,
+    or_else: Option<String>,
+}
+
+impl NodeMemberBuild {
+    pub fn new(kind: &str, with: &str, or_else: Option<String>) -> Self {
+        Self {
+            kind: kind.to_string(),
+            with: with.to_string(),
+            or_else,
+        }
+    }
+
+    /// The type to build, in Pascal case.
+    pub fn kind(&self) -> &str {
+        &self.kind
+    }
+
+    pub fn with(&self) -> &str {
+        &self.with
+    }
+
+    /// The default fn to call when unwrapping the child (before passing as arg to new).
+    pub fn or_else(&self) -> Option<&str> {
+        self.or_else.as_deref()
+    }
+}
+
+#[derive(Debug)]
+pub struct BooleanMemberBuild {
+    on: BooleanMemberBuildOn,
+}
+
+impl BooleanMemberBuild {
+    pub fn new(on: BooleanMemberBuildOn) -> Self {
+        Self { on }
+    }
+
+    pub fn on(&self) -> &BooleanMemberBuildOn {
+        &self.on
+    }
+}
+
+#[derive(Debug)]
+pub enum BooleanMemberBuildOn {
+    RulePresent,
+}

ast-generator/src/spec/tree_enum_spec.rs

@@ -0,0 +1,117 @@
+pub struct TreeEnumBuildSpec {
+    build: String,
+    rules: Vec<Box<TreeEnumRule>>,
+}
+
+impl TreeEnumBuildSpec {
+    pub fn new(build: &str, rules: Vec<Box<TreeEnumRule>>) -> Self {
+        TreeEnumBuildSpec {
+            build: build.to_string(),
+            rules,
+        }
+    }
+
+    /// The enum type to be built, in Pascal case.
+    pub fn build(&self) -> &str {
+        &self.build
+    }
+
+    /// The individual rule specs.
+    pub fn rules(&self) -> impl Iterator<Item = &TreeEnumRule> {
+        self.rules.iter().map(Box::as_ref)
+    }
+}
+
+pub struct TreeEnumRule {
+    rule: String,
+    child: Option<Box<EnumRuleChild>>,
+}
+
+impl TreeEnumRule {
+    pub fn new(rule: &str, child: Option<Box<EnumRuleChild>>) -> Self {
+        Self {
+            rule: rule.to_string(),
+            child,
+        }
+    }
+
+    /// The enum rule to match, in Pascal case.
+    pub fn rule(&self) -> &str {
+        &self.rule
+    }
+
+    pub fn child(&self) -> Option<&EnumRuleChild> {
+        if let Some(child) = &self.child {
+            Some(child.as_ref())
+        } else {
+            None
+        }
+    }
+}
+
+pub struct EnumRuleChild {
+    kind: Box<EnumRuleChildKind>,
+}
+
+impl EnumRuleChild {
+    pub fn new(kind: Box<EnumRuleChildKind>) -> Self {
+        Self { kind }
+    }
+
+    pub fn kind(&self) -> &EnumRuleChildKind {
+        &self.kind
+    }
+}
+
+pub enum EnumRuleChildKind {
+    Node(EnumRuleChildNodeKind),
+    Int(NameAndWith),
+    Long(NameAndWith),
+    Double(NameAndWith),
+    String(NameAndWith),
+    Boolean(NameAndWith),
+}
+
+pub struct EnumRuleChildNodeKind {
+    node_kind: String,
+    with: String,
+}
+
+impl EnumRuleChildNodeKind {
+    pub fn new(node_kind: &str, with: &str) -> Self {
+        Self {
+            node_kind: node_kind.to_string(),
+            with: with.to_string(),
+        }
+    }
+
+    pub fn node_kind(&self) -> &str {
+        &self.node_kind
+    }
+    
+    pub fn with(&self) -> &str {
+        &self.with
+    }
+}
+
+pub struct NameAndWith {
+    name: String,
+    with: String,
+}
+
+impl NameAndWith {
+    pub fn new(name: &str, with: &str) -> Self {
+        Self {
+            name: name.to_string(),
+            with: with.to_string(),
+        }
+    }
+    
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+    
+    pub fn with(&self) -> &str {
+        &self.with
+    }
+}

ast-generator/src/type_gen.rs

@@ -1,162 +0,0 @@
-use crate::spec::{
-    BuildSpec, ChildSpec, EnumBuildSpec, SingleBooleanChildToBuild, SingleChildToBuild,
-    SingleTypeChildToBuild, StructBuildSpec, VecChild, VecChildToBuild,
-};
-use proc_macro2::{Ident, TokenStream};
-use quote::{format_ident, quote};
-
-fn make_enum_type(build_spec: &EnumBuildSpec) -> TokenStream {
-    let children: Vec<TokenStream> = build_spec
-        .rules()
-        .iter()
-        .map(|rule| {
-            let member_name_ident = format_ident!("{}", rule.rule());
-            let child_name_ident = format_ident!("{}", rule.build());
-            quote! {
-                #member_name_ident(#child_name_ident)
-            }
-        })
-        .collect();
-    let type_name_ident = format_ident!("{}", build_spec.build());
-    quote! {
-        pub enum #type_name_ident {
-            #(#children),*
-        }
-    }
-}
-
-fn handle_vec_child(
-    vec_child: &VecChild,
-    member_names: &mut Vec<Ident>,
-    annotated_members: &mut Vec<TokenStream>,
-    accessors: &mut Vec<TokenStream>,
-) {
-    let (child_ident, child_ident_mut, child_type_ident) = match vec_child.build() {
-        VecChildToBuild::Type(vec_type_child) => (
-            format_ident!("{}", vec_type_child.var_name()),
-            format_ident!("{}_mut", vec_type_child.var_name()),
-            format_ident!("{}", vec_type_child.build()),
-        ),
-    };
-
-    member_names.push(child_ident.clone());
-    annotated_members.push(quote! {
-        #child_ident: Vec<Box<#child_type_ident>>
-    });
-    accessors.push(quote! {
-        pub fn #child_ident(&self) -> impl Iterator<Item = &#child_type_ident> {
-            self.#child_ident.iter().map(Box::as_ref)
-        }
-
-        pub fn #child_ident_mut(&mut self) -> impl Iterator<Item = &mut #child_type_ident> {
-            self.#child_ident.iter_mut().map(Box::as_mut)
-        }
-    });
-}
-
-fn handle_single_type_child(
-    single_type_child: &SingleTypeChildToBuild,
-    member_names: &mut Vec<Ident>,
-    annotated_members: &mut Vec<TokenStream>,
-    accessors: &mut Vec<TokenStream>,
-) {
-    let child_ident = format_ident!("{}", single_type_child.var_name());
-    let child_ident_mut = format_ident!("{}_mut", single_type_child.var_name());
-    let child_type_ident = format_ident!("{}", single_type_child.build());
-    member_names.push(child_ident.clone());
-    annotated_members.push(quote! {
-        #child_ident: Box<#child_type_ident>
-    });
-    accessors.push(quote! {
-        pub fn #child_ident(&self) -> &#child_type_ident {
-            self.#child_ident.as_ref()
-        }
-
-        pub fn #child_ident_mut(&mut self) -> &mut #child_type_ident {
-            self.#child_ident.as_mut()
-        }
-    });
-}
-
-fn handle_single_boolean_child(
-    single_boolean_child: &SingleBooleanChildToBuild,
-    member_names: &mut Vec<Ident>,
-    annotated_members: &mut Vec<TokenStream>,
-    accessors: &mut Vec<TokenStream>,
-) {
-    let child_ident = format_ident!("{}", single_boolean_child.var_name());
-    member_names.push(child_ident.clone());
-    annotated_members.push(quote! {
-        #child_ident: bool
-    });
-    accessors.push(quote! {
-        pub fn #child_ident(&self) -> bool {
-            self.#child_ident
-        }
-    })
-}
-
-fn make_struct_type(build_spec: &StructBuildSpec) -> TokenStream {
-    let mut member_names: Vec<Ident> = vec![];
-    let mut annotated_members: Vec<TokenStream> = vec![];
-    let mut accessors: Vec<TokenStream> = vec![];
-
-    for child_spec in build_spec.children().iter() {
-        match child_spec {
-            ChildSpec::SkipChild(_) => {}
-            ChildSpec::VecChild(vec_child) => {
-                handle_vec_child(
-                    vec_child,
-                    &mut member_names,
-                    &mut annotated_members,
-                    &mut accessors,
-                );
-            }
-            ChildSpec::SingleChild(single_child) => {
-                match single_child.build() {
-                    SingleChildToBuild::Type(single_type_child) => {
-                        handle_single_type_child(
-                            single_type_child,
-                            &mut member_names,
-                            &mut annotated_members,
-                            &mut accessors,
-                        );
-                    }
-                    SingleChildToBuild::Boolean(single_boolean_child) => {
-                        handle_single_boolean_child(
-                            single_boolean_child,
-                            &mut member_names,
-                            &mut annotated_members,
-                            &mut accessors,
-                        );
-                    }
-                };
-            }
-        }
-    }
-
-    let type_ident = format_ident!("{}", build_spec.build());
-
-    quote! {
-        pub struct #type_ident {
-            #(#annotated_members),*
-        }
-
-        impl #type_ident {
-            pub fn new(#(#annotated_members),*) -> Self {
-                Self {
-                    #(#member_names),*
-                }
-            }
-
-            #(#accessors)*
-        }
-    }
-}
-
-pub fn make_type(build_spec: &BuildSpec) -> TokenStream {
-    match build_spec {
-        BuildSpec::Enum(enum_build_spec) => make_enum_type(enum_build_spec),
-        BuildSpec::Struct(struct_build_spec) => make_struct_type(struct_build_spec),
-    }
-}

ast-generator/src/type_gen/enum_type.rs

@@ -0,0 +1,37 @@
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+use crate::spec::tree_enum_spec::{EnumRuleChildKind, TreeEnumBuildSpec};
+
+pub fn make_enum_type(build_spec: &TreeEnumBuildSpec) -> TokenStream {
+    let children: Vec<TokenStream> = build_spec
+        .rules()
+        .map(|enum_rule| {
+            let member_name_ident = format_ident!("{}", enum_rule.rule());
+            if let Some(enum_rule_child) = enum_rule.child() {
+                let child_type_ident = match enum_rule_child.kind() {
+                    EnumRuleChildKind::Node(node_child) => {
+                        format_ident!("{}", node_child.node_kind())
+                    }
+                    EnumRuleChildKind::Int(_) => format_ident!("i32"),
+                    EnumRuleChildKind::Long(_) => format_ident!("i64"),
+                    EnumRuleChildKind::Double(_) => format_ident!("f64"),
+                    EnumRuleChildKind::String(_) => format_ident!("String"),
+                    EnumRuleChildKind::Boolean(_) => format_ident!("bool"),
+                };
+                quote! {
+                    #member_name_ident(#child_type_ident)
+                }
+            } else {
+                quote! {
+                    #member_name_ident
+                }
+            }
+        })
+        .collect();
+    let type_name_ident = format_ident!("{}", build_spec.build());
+    quote! {
+        pub enum #type_name_ident {
+            #(#children),*
+        }
+    }
+}

ast-generator/src/type_gen/leaf_enum_type.rs

@@ -0,0 +1,22 @@
+use crate::spec::leaf_enum_spec::LeafEnumBuildSpec;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_leaf_enum_type(build_spec: &LeafEnumBuildSpec) -> TokenStream {
+    let type_name_ident = format_ident!("{}", build_spec.build());
+    let children = build_spec
+        .rules()
+        .map(|leaf_enum_rule| {
+            let rule_name_ident = format_ident!("{}", leaf_enum_rule);
+            quote! {
+                #rule_name_ident
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        pub enum #type_name_ident {
+            #(#children),*
+        }
+    }
+}

ast-generator/src/type_gen/leaf_struct_type.rs

@@ -0,0 +1,118 @@
+use crate::spec::leaf_struct_spec::{LeafStructBuildSpec, LeafStructMemberKind};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_leaf_struct_type(build_spec: &LeafStructBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", build_spec.build());
+
+    let annotated_members = build_spec
+        .members()
+        .map(|member| {
+            let name_ident = format_ident!("{}", member.name());
+            let type_ident = match member.kind() {
+                LeafStructMemberKind::String => quote! { String },
+                LeafStructMemberKind::FileId => quote! { usize },
+                LeafStructMemberKind::Range => quote! { Range<usize> },
+            };
+            quote! {
+                #name_ident: #type_ident
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let member_args = build_spec.members().map(|member| {
+        let name_ident = format_ident!("{}", member.name());
+        let type_stream = match member.kind() {
+            LeafStructMemberKind::String => {
+                quote! { &str }
+            }
+            LeafStructMemberKind::FileId => {
+                quote! { usize }
+            }
+            LeafStructMemberKind::Range => {
+                quote! { Range<usize> }
+            }
+        };
+        quote! {
+            #name_ident: #type_stream
+        }
+    });
+
+    let initializers = build_spec
+        .members()
+        .map(|leaf_struct_member| {
+            let member_ident = format_ident!("{}", leaf_struct_member.name());
+            match leaf_struct_member.kind() {
+                LeafStructMemberKind::String => {
+                    quote! {
+                        #member_ident: #member_ident.to_string()
+                    }
+                }
+                _ => quote! { #member_ident },
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let accessors = build_spec
+        .members()
+        .map(|member| {
+            let name_ident = format_ident!("{}", member.name());
+            match member.kind() {
+                LeafStructMemberKind::String => {
+                    quote! {
+                        pub fn #name_ident(&self) -> &str {
+                            &self.#name_ident
+                        }
+                    }
+                }
+                LeafStructMemberKind::FileId => {
+                    quote! {
+                        pub fn #name_ident(&self) -> usize {
+                            self.#name_ident
+                        }
+                    }
+                }
+                LeafStructMemberKind::Range => {
+                    quote! {
+                        pub fn #name_ident(&self) -> Range<usize> {
+                            self.#name_ident
+                        }
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let struct_stream = if build_spec.derive().count() > 0 {
+        let derives = build_spec.derive().map(|derive| {
+            format_ident!("{}", derive)
+        }).collect::<Vec<_>>();
+        
+        quote! {
+            #[derive(#(#derives),*)]
+            pub struct #type_ident {
+                #(#annotated_members),*
+            }
+        }
+    } else {
+        quote! {
+            pub struct #type_ident {
+                #(#annotated_members),*
+            }
+        }
+    };
+    
+    quote! {
+        #struct_stream
+
+        impl #type_ident {
+            pub fn new(#(#member_args),*) -> Self {
+                Self {
+                    #(#initializers),*
+                }
+            }
+
+            #(#accessors)*
+        }
+    }
+}

ast-generator/src/type_gen/mod.rs

@@ -0,0 +1,44 @@
+mod enum_type;
+mod leaf_enum_type;
+mod leaf_struct_type;
+mod polymorphic_enum_inner_build_type;
+mod polymorphic_enum_loop_type;
+mod polymorphic_type_type;
+mod struct_type;
+
+use crate::spec::BuildSpec;
+use crate::type_gen::enum_type::make_enum_type;
+use crate::type_gen::leaf_enum_type::make_leaf_enum_type;
+use crate::type_gen::leaf_struct_type::make_leaf_struct_type;
+use crate::type_gen::polymorphic_enum_inner_build_type::make_polymorphic_enum_inner_build_type;
+use crate::type_gen::polymorphic_enum_loop_type::make_polymorphic_enum_loop_type;
+use crate::type_gen::polymorphic_type_type::make_polymorphic_type_type;
+use crate::type_gen::struct_type::make_struct_type;
+use proc_macro2::TokenStream;
+
+pub fn make_type(build_spec: &BuildSpec) -> Option<TokenStream> {
+    match build_spec {
+        BuildSpec::Struct(struct_build_spec) => Some(make_struct_type(struct_build_spec)),
+        BuildSpec::LeafStruct(leaf_struct_build_spec) => {
+            Some(make_leaf_struct_type(leaf_struct_build_spec))
+        }
+        BuildSpec::Enum(enum_build_spec) => Some(make_enum_type(enum_build_spec)),
+        BuildSpec::LeafEnum(leaf_enum_build_spec) => {
+            Some(make_leaf_enum_type(leaf_enum_build_spec))
+        }
+        BuildSpec::Production(_) => None,
+        BuildSpec::NodeProduction(_) => None,
+        BuildSpec::PolymorphicType(polymorphic_build_spec) => {
+            Some(make_polymorphic_type_type(polymorphic_build_spec))
+        }
+        BuildSpec::PolymorphicEnumLoop(polymorphic_enum_loop_spec) => {
+            Some(make_polymorphic_enum_loop_type(polymorphic_enum_loop_spec))
+        }
+        BuildSpec::PolymorphicPassThrough(_) => None,
+        BuildSpec::PolymorphicEnumInnerBuild(polymorphic_enum_inner_build_spec) => Some(
+            make_polymorphic_enum_inner_build_type(polymorphic_enum_inner_build_spec),
+        ),
+        BuildSpec::PolymorphicLeafEnum(_) => None,
+        BuildSpec::PolymorphicTreeEnum(_) => None,
+    }
+}

ast-generator/src/type_gen/polymorphic_enum_inner_build_type.rs

@@ -0,0 +1,25 @@
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+use crate::spec::polymorphic_enum_inner_build::{PolymorphicEnumInnerBuild, PolymorphicEnumInnerBuildMemberKind};
+
+pub fn make_polymorphic_enum_inner_build_type(spec: &PolymorphicEnumInnerBuild) -> TokenStream {
+    let members = spec.members()
+        .map(|member| {
+            let name_ident = format_ident!("{}", member.name());
+            match member.kind() {
+                PolymorphicEnumInnerBuildMemberKind::Leaf => {
+                    quote! { #name_ident }
+                }
+                PolymorphicEnumInnerBuildMemberKind::Struct => {
+                    quote! { #name_ident(#name_ident) }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+    let type_name_ident = format_ident!("{}", spec.name());
+    quote! {
+        pub enum #type_name_ident {
+            #(#members,)*
+        }
+    }
+}

ast-generator/src/type_gen/polymorphic_enum_loop_type.rs

@@ -0,0 +1,193 @@
+use crate::spec::polymorphic_enum_loop_spec::{
+    PolymorphicEnumLoopBuildSpec, PolymorphicEnumLoopRule, PolymorphicEnumLoopRuleBuildChild,
+};
+use crate::spec::SpecialChildKind;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_enum_loop_type(spec: &PolymorphicEnumLoopBuildSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", spec.name());
+
+    let build = spec
+        .rules()
+        .find(|rule| match rule {
+            PolymorphicEnumLoopRule::Build(_) => true,
+            _ => false,
+        })
+        .map(|rule| match rule {
+            PolymorphicEnumLoopRule::Build(build) => build,
+            _ => unreachable!(),
+        })
+        .unwrap();
+
+    let annotated_members = build
+        .children()
+        .map(|child| match child {
+            PolymorphicEnumLoopRuleBuildChild::UseCurrent(use_current) => {
+                let child_ident = format_ident!("{}", use_current.name());
+                let child_type_ident = format_ident!("{}", use_current.kind());
+                quote! {
+                    #child_ident: Box<#child_type_ident>
+                }
+            }
+            PolymorphicEnumLoopRuleBuildChild::OnEach(on_each) => {
+                let child_ident = format_ident!("{}", on_each.name());
+                let child_type_ident = format_ident!("{}", on_each.rule());
+                quote! {
+                    #child_ident: Box<#child_type_ident>
+                }
+            }
+            PolymorphicEnumLoopRuleBuildChild::Special(special_child) => {
+                let child_ident = format_ident!("{}", special_child.name());
+                let child_type_ident = match special_child.kind() {
+                    SpecialChildKind::FileId => {
+                        quote! { usize }
+                    }
+                    SpecialChildKind::Range => {
+                        quote! { Range<usize> }
+                    }
+                };
+                quote! {
+                    #child_ident: #child_type_ident
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let annotated_fields = build
+        .fields()
+        .iter()
+        .map(|field| {
+            let field_ident = format_ident!("{}", field.name());
+            let field_type = format_ident!("{}", field.kind());
+            quote! {
+                #field_ident: Option<#field_type>
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let member_names = build
+        .children()
+        .map(|child| match child {
+            PolymorphicEnumLoopRuleBuildChild::UseCurrent(use_current) => {
+                format_ident!("{}", use_current.name())
+            }
+            PolymorphicEnumLoopRuleBuildChild::OnEach(on_each) => {
+                format_ident!("{}", on_each.name())
+            }
+            PolymorphicEnumLoopRuleBuildChild::Special(special_child) => {
+                format_ident!("{}", special_child.name())
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let field_initializers = build
+        .fields()
+        .iter()
+        .map(|field| {
+            let field_ident = format_ident!("{}", field.name());
+            quote! { #field_ident: None }
+        })
+        .collect::<Vec<_>>();
+
+    let accessors = build
+        .children()
+        .map(|child| {
+            let (child_ident, child_type_ident) = match child {
+                PolymorphicEnumLoopRuleBuildChild::UseCurrent(use_current) => {
+                    let child_ident = format_ident!("{}", use_current.name());
+                    let child_type_ident = format_ident!("{}", use_current.kind());
+                    (child_ident, quote! { #child_type_ident })
+                }
+                PolymorphicEnumLoopRuleBuildChild::OnEach(on_each) => {
+                    let child_ident = format_ident!("{}", on_each.name());
+                    let child_type_ident = format_ident!("{}", on_each.rule());
+                    (child_ident, quote! { #child_type_ident })
+                }
+                PolymorphicEnumLoopRuleBuildChild::Special(special_child) => {
+                    let child_ident = format_ident!("{}", special_child.name());
+                    let child_type_ident = match special_child.kind() {
+                        SpecialChildKind::FileId => {
+                            quote! { usize }
+                        }
+                        SpecialChildKind::Range => {
+                            quote! { Range<usize> }
+                        }
+                    };
+                    (child_ident, child_type_ident)
+                }
+            };
+            let child_mut_ident = format_ident!("{}_mut", child_ident);
+
+            let as_ref = match child {
+                PolymorphicEnumLoopRuleBuildChild::Special(_) => {
+                    quote! { &self.#child_ident }
+                }
+                _ => quote! { self.#child_ident.as_ref() },
+            };
+
+            let as_mut = match child {
+                PolymorphicEnumLoopRuleBuildChild::Special(_) => {
+                    quote! { &mut self.#child_ident }
+                }
+                _ => quote! { self.#child_ident.as_mut() },
+            };
+
+            quote! {
+                pub fn #child_ident(&self) -> &#child_type_ident {
+                    #as_ref
+                }
+
+                pub fn #child_mut_ident(&mut self) -> &mut #child_type_ident {
+                    #as_mut
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let field_accessors = build
+        .fields()
+        .iter()
+        .map(|field| {
+            let field_ident = format_ident!("{}", field.name());
+            let field_ident_mut = format_ident!("{}_mut", field.name());
+            let field_type = format_ident!("{}", field.kind());
+
+            let set_ident = format_ident!("set_{}", field.name());
+
+            quote! {
+                pub fn #field_ident(&self) -> Option<&#field_type> {
+                    self.#field_ident.as_ref()
+                }
+
+                pub fn #field_ident_mut(&mut self) -> Option<&mut #field_type> {
+                    self.#field_ident.as_mut()
+                }
+
+                pub fn #set_ident(&mut self, #field_ident: #field_type) {
+                    self.#field_ident = Some(#field_ident);
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    quote! {
+        pub struct #type_ident {
+            #(#annotated_members,)*
+            #(#annotated_fields,)*
+        }
+
+        impl #type_ident {
+            pub fn new(#(#annotated_members),*) -> Self {
+                Self {
+                    #(#member_names,)*
+                    #(#field_initializers,)*
+                }
+            }
+
+            #(#accessors)*
+
+            #(#field_accessors)*
+        }
+    }
+}

ast-generator/src/type_gen/polymorphic_type_type.rs

@@ -0,0 +1,22 @@
+use crate::spec::polymorphic_type_spec::PolymorphicTypeBuildSpec;
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+pub fn make_polymorphic_type_type(build_spec: &PolymorphicTypeBuildSpec) -> TokenStream {
+    let members = build_spec
+        .variants()
+        .map(|enum_member| {
+            let member_ident = format_ident!("{}", enum_member.name());
+            let inner_type_ident = format_ident!("{}", enum_member.inner_kind());
+            quote! {
+                #member_ident(#inner_type_ident)
+            }
+        })
+        .collect::<Vec<_>>();
+    let type_name_ident = format_ident!("{}", build_spec.name());
+    quote! {
+        pub enum #type_name_ident {
+            #(#members),*
+        }
+    }
+}

ast-generator/src/type_gen/struct_type.rs

@@ -0,0 +1,339 @@
+use crate::spec::struct_spec::{
+    MemberChild, MemberChildBuild, StructChild, StructSpec, VecChild, VecChildBuild,
+};
+use crate::spec::{SpecialChild, SpecialChildKind, StructField, StructFieldWrap};
+use proc_macro2::{Ident, TokenStream};
+use quote::{format_ident, quote};
+
+fn make_field_accessors(field: &StructField) -> TokenStream {
+    let field_ident = format_ident!("{}", field.name());
+    let field_type = {
+        let inner = format_ident!("{}", field.kind());
+        if let Some(wrap) = field.wrap() {
+            match wrap {
+                StructFieldWrap::RcRefCell => {
+                    quote! { Rc<RefCell<#inner>> }
+                }
+            }
+        } else {
+            quote! { #inner }
+        }
+    };
+    let field_ident_mut = format_ident!("{}_mut", field.name());
+
+    if field.vec() {
+        quote! {
+            pub fn #field_ident(&self) -> &[#field_type] {
+                self.#field_ident.as_slice()
+            }
+
+            pub fn #field_ident_mut(&mut self) -> &mut Vec<#field_type> {
+                &mut self.#field_ident
+            }
+        }
+    } else {
+        let set_field_ident = format_ident!("set_{}", field.name());
+        quote! {
+            pub fn #field_ident(&self) -> Option<&#field_type> {
+                self.#field_ident.as_ref()
+            }
+
+            pub fn #field_ident_mut(&mut self) -> Option<&mut #field_type> {
+                self.#field_ident.as_mut()
+            }
+
+            pub fn #set_field_ident(&mut self, #field_ident: #field_type) {
+                self.#field_ident = Some(#field_ident);
+            }
+        }
+    }
+}
+
+fn make_field_initializer(field: &StructField) -> TokenStream {
+    let field_ident = format_ident!("{}", field.name());
+    if field.vec() {
+        quote! { #field_ident: vec![] }
+    } else {
+        quote! { #field_ident: None }
+    }
+}
+
+fn make_annotated_field(field: &StructField) -> TokenStream {
+    let field_ident = format_ident!("{}", field.name());
+    let field_type = if let Some(wrap) = field.wrap() {
+        let inner = format_ident!("{}", field.kind());
+        match wrap {
+            StructFieldWrap::RcRefCell => {
+                quote! { Rc<RefCell<#inner>> }
+            }
+        }
+    } else {
+        let inner = format_ident!("{}", field.kind());
+        quote! { #inner }
+    };
+
+    if field.vec() {
+        quote! {
+            #field_ident: Vec<#field_type>
+        }
+    } else {
+        quote! {
+            #field_ident: Option<#field_type>
+        }
+    }
+}
+
+fn make_vec_child_accessors(vec_child: &VecChild) -> TokenStream {
+    let child_ident = format_ident!("{}", vec_child.name());
+    match vec_child.build() {
+        VecChildBuild::String(_) => {
+            quote! {
+                pub fn #child_ident(&self) -> impl Iterator<Item = &str> {
+                    self.#child_ident.iter().map(String::as_str)
+                }
+            }
+        }
+        VecChildBuild::Node(vec_child_node_build) => {
+            let child_type_ident = format_ident!("{}", vec_child_node_build.kind());
+            let child_ident_mut = format_ident!("{}_mut", vec_child.name());
+
+            quote! {
+                pub fn #child_ident(&self) -> impl Iterator<Item = &#child_type_ident> {
+                    self.#child_ident.iter().map(Box::as_ref)
+                }
+
+                pub fn #child_ident_mut(&mut self) -> impl Iterator<Item = &mut #child_type_ident> {
+                    self.#child_ident.iter_mut().map(Box::as_mut)
+                }
+            }
+        }
+    }
+}
+
+fn make_member_child_accessors(member_child: &MemberChild) -> TokenStream {
+    let child_ident = format_ident!("{}", member_child.name());
+    match member_child.build() {
+        MemberChildBuild::Node(node_member_build) => {
+            let return_type_ident = format_ident!("{}", node_member_build.kind());
+            let child_ident_mut = format_ident!("{}_mut", member_child.name());
+
+            if member_child.optional() {
+                quote! {
+                    pub fn #child_ident(&self) -> Option<&#return_type_ident> {
+                        if let Some(#child_ident) = &self.#child_ident {
+                            Some(#child_ident.as_ref())
+                        } else {
+                            None
+                        }
+                    }
+
+                    pub fn #child_ident_mut(&mut self) -> Option<&mut #return_type_ident> {
+                        if let Some(#child_ident) = &mut self.#child_ident {
+                            Some(#child_ident.as_mut())
+                        } else {
+                            None
+                        }
+                    }
+                }
+            } else {
+                quote! {
+                    pub fn #child_ident(&self) -> &#return_type_ident {
+                        self.#child_ident.as_ref()
+                    }
+
+                    pub fn #child_ident_mut(&mut self) -> &mut #return_type_ident {
+                        self.#child_ident.as_mut()
+                    }
+                }
+            }
+        }
+        MemberChildBuild::Boolean(_) => {
+            quote! {
+                pub fn #child_ident(&self) -> bool {
+                    self.#child_ident
+                }
+            }
+        }
+    }
+}
+
+fn make_special_child_accessors(special_child: &SpecialChild) -> TokenStream {
+    let child_ident = format_ident!("{}", special_child.name());
+    match special_child.kind() {
+        SpecialChildKind::FileId => {
+            quote! {
+                pub fn #child_ident(&self) -> usize {
+                    self.#child_ident
+                }
+            }
+        }
+        SpecialChildKind::Range => {
+            quote! {
+                pub fn #child_ident(&self) -> Range<usize> {
+                    self.#child_ident
+                }
+            }
+        }
+    }
+}
+
+fn make_accessors(child: &StructChild) -> Option<TokenStream> {
+    match child {
+        StructChild::SkipChild(_) => None,
+        StructChild::VecChild(vec_child) => Some(make_vec_child_accessors(vec_child)),
+        StructChild::MemberChild(member_child) => Some(make_member_child_accessors(member_child)),
+        StructChild::Special(special_child) => Some(make_special_child_accessors(special_child)),
+    }
+}
+
+fn make_member_ident(child: &StructChild) -> Option<Ident> {
+    match child {
+        StructChild::SkipChild(_) => None,
+        StructChild::VecChild(vec_child) => Some(format_ident!("{}", vec_child.name())),
+        StructChild::MemberChild(member_child) => Some(format_ident!("{}", member_child.name())),
+        StructChild::Special(special_child) => Some(format_ident!("{}", special_child.name())),
+    }
+}
+
+fn make_vec_child_annotated_member(vec_child: &VecChild) -> TokenStream {
+    let child_ident = format_ident!("{}", vec_child.name());
+    let type_stream = match vec_child.build() {
+        VecChildBuild::String(_) => quote! { String },
+        VecChildBuild::Node(vec_child_node_build) => {
+            let type_ident = format_ident!("{}", vec_child_node_build.kind());
+            quote! { Box<#type_ident> }
+        }
+    };
+
+    quote! {
+        #child_ident: Vec<#type_stream>
+    }
+}
+
+fn make_member_child_type_ident(member_child: &MemberChild) -> TokenStream {
+    match member_child.build() {
+        MemberChildBuild::Node(node_member_build) => {
+            let type_ident = format_ident!("{}", node_member_build.kind());
+            quote! { Box<#type_ident> }
+        }
+        MemberChildBuild::Boolean(_) => {
+            quote! { bool }
+        }
+    }
+}
+
+fn make_member_child_annotated_member(member_child: &MemberChild) -> TokenStream {
+    let child_name_ident = format_ident!("{}", member_child.name());
+    let type_ident = make_member_child_type_ident(member_child);
+    let type_stream = if member_child.optional() {
+        quote! { Option<#type_ident> }
+    } else {
+        quote! { #type_ident }
+    };
+
+    quote! {
+        #child_name_ident: #type_stream
+    }
+}
+
+fn make_special_child_annotated_member(special_child: &SpecialChild) -> TokenStream {
+    let child_ident = format_ident!("{}", special_child.name());
+    let child_type_ident = match special_child.kind() {
+        SpecialChildKind::FileId => quote! { usize },
+        SpecialChildKind::Range => quote! { Range<usize> },
+    };
+    quote! {
+        #child_ident: #child_type_ident
+    }
+}
+
+fn make_annotated_member(child: &StructChild) -> Option<TokenStream> {
+    match child {
+        StructChild::SkipChild(_) => None,
+        StructChild::VecChild(vec_child) => Some(make_vec_child_annotated_member(vec_child)),
+        StructChild::MemberChild(member_child) => {
+            Some(make_member_child_annotated_member(member_child))
+        }
+        StructChild::Special(special_child) => {
+            Some(make_special_child_annotated_member(special_child))
+        }
+    }
+}
+
+pub fn make_struct_type(build_spec: &StructSpec) -> TokenStream {
+    let type_ident = format_ident!("{}", build_spec.build());
+    let annotated_children_members = build_spec
+        .children()
+        .map(|child| make_annotated_member(child))
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let annotated_fields = build_spec
+        .fields()
+        .map(|field| make_annotated_field(field))
+        .collect::<Vec<_>>();
+
+    let member_names = build_spec
+        .children()
+        .map(|child| make_member_ident(child))
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let field_initializers = build_spec
+        .fields()
+        .map(|field| make_field_initializer(field))
+        .collect::<Vec<_>>();
+
+    let child_accessors = build_spec
+        .children()
+        .map(|child| make_accessors(child))
+        .filter(Option::is_some)
+        .map(Option::unwrap)
+        .collect::<Vec<_>>();
+
+    let field_accessors = build_spec
+        .fields()
+        .map(|field| make_field_accessors(field))
+        .collect::<Vec<_>>();
+
+    let struct_stream = {
+        let base = quote! {
+            pub struct #type_ident {
+                #(#annotated_children_members,)*
+                #(#annotated_fields,)*
+            }
+        };
+        if !build_spec.derive().is_empty() {
+            let derives = build_spec
+                .derive()
+                .iter()
+                .map(|derive| format_ident!("{}", derive))
+                .collect::<Vec<_>>();
+
+            quote! {
+                #[derive(#(#derives,)*)]
+                #base
+            }
+        } else {
+            base
+        }
+    };
+
+    quote! {
+        #struct_stream
+
+        impl #type_ident {
+            pub fn new(#(#annotated_children_members),*) -> Self {
+                Self {
+                    #(#member_names,)*
+                    #(#field_initializers,)*
+                }
+            }
+
+            #(#child_accessors)*
+            #(#field_accessors)*
+        }
+    }
+}

ast-generator/src/walk.rs

@@ -0,0 +1,18 @@
+use crate::spec::BuildSpec;
+use proc_macro2::TokenStream;
+use quote::quote;
+
+pub fn make_walk_fn(specs: &[BuildSpec]) -> TokenStream {
+    quote! {
+        use crate::ast::node::*;
+        use crate::ast::ast_node::*;
+
+        pub fn walk_depth_first<'a>(node: &'a dyn AstNode<'a>, f: &mut impl FnMut(AstNodeRef<'a>)) {
+            use AstNodeRef::*;
+            for child in node.children() {
+                walk_depth_first(child, f);
+            }
+            f(node.as_node_ref());
+        }
+    }
+}

build.rs

@@ -1,9 +1,40 @@
-fn main() -> std::io::Result<()> {
-    println!("cargo:rerun-if-changed=src/parser/deimos.pest");
-    // let out_dir = env::var("OUT_DIR").unwrap();
-    // let out_dir_path = Path::new(&out_dir);
-    // let testing_txt_path = out_dir_path.join("testing.rs");
-    // let output = test_dump();
-    // write(&testing_txt_path, output)?;
+use ast_generator::{get_build_specs, generate_files};
+use cst_test_generator::generate_test_files;
+use std::env;
+use std::fs;
+use std::io;
+use std::path::Path;
+
+fn generate_parser_tests(out_dir: &Path) -> io::Result<()> {
+    let parser_tests_dir = out_dir.join("src").join("parser").join("tests");
+    fs::create_dir_all(&parser_tests_dir)?;
+    let test_suites_file = generate_test_files(Path::new("src/parser/tests"))?;
+    let file_path = parser_tests_dir.join(&test_suites_file.file_name);
+    fs::write(file_path, &test_suites_file.contents)?;
+    Ok(())
+}
+
+fn generate_ast_files(out_dir: &Path) -> io::Result<()> {
+    let gen_ast_dir = out_dir.join("src").join("ast");
+    fs::create_dir_all(&gen_ast_dir)?;
+
+    let ast_yaml = include_str!("src/parser/ast.yaml");
+    let build_specs = get_build_specs(ast_yaml);
+    let generated_files = generate_files(&build_specs);
+    for generated_file in &generated_files {
+        let path = gen_ast_dir.join(&generated_file.name);
+        fs::write(path, &generated_file.contents)?;
+    }
+    Ok(())
+}
+
+fn main() -> io::Result<()> {
+    println!("cargo:rerun-if-changed=src/parser/tests");
+    println!("cargo:rerun-if-changed=src/parser/ast.yaml");
+    println!("cargo:rerun-if-changed=src/parser/deimos.pest");
+    let out_dir = env::var_os("OUT_DIR").unwrap();
+    let out_dir_path = Path::new(&out_dir);
+    generate_parser_tests(out_dir_path)?;
+    generate_ast_files(out_dir_path)?;
     Ok(())
 }

cst-test-generator/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "cst-test-generator"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+convert_case = "0.8.0"
+prettyplease = "0.2.37"
+proc-macro2 = "1.0.101"
+quote = "1.0.40"
+syn = "2.0.106"

cst-test-generator/src/lib.rs

@@ -0,0 +1,72 @@
+use convert_case::{Case, Casing};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+use std::path::Path;
+use std::{fs, io};
+use syn::File;
+
+pub struct ParserTestSuitesFile {
+    pub file_name: String,
+    pub contents: String,
+}
+
+pub fn generate_test_files(tests_dir: &Path) -> io::Result<ParserTestSuitesFile> {
+    let mut test_suites: Vec<TokenStream> = vec![];
+
+    // generate test file for each sub dir
+    for sub_dir in fs::read_dir(tests_dir)? {
+        let sub_dir = sub_dir?;
+        let sub_dir_path = sub_dir.path();
+        if sub_dir_path.is_dir() {
+            let sub_dir_file_name = sub_dir.file_name();
+            let sub_dir_string = sub_dir_file_name.to_string_lossy();
+
+            let sub_dir_pascal = sub_dir_string.to_case(Case::Pascal);
+            let rule_ident = format_ident!("{}", sub_dir_pascal);
+
+            let mut tests: Vec<TokenStream> = vec![];
+            for test_file in fs::read_dir(sub_dir_path)? {
+                let test_file = test_file?;
+                let test_file_name = test_file.file_name();
+                let test_ident = format_ident!("{}", test_file_name.to_string_lossy());
+
+                let src_input = fs::read_to_string(test_file.path())?;
+
+                let test = quote! {
+                    #[test]
+                    fn #test_ident() {
+                        parses_to(Rule::#rule_ident, #src_input)
+                    }
+                };
+
+                tests.push(test);
+            }
+
+            let tests_mod_ident = format_ident!("{}_tests", sub_dir.file_name().to_string_lossy());
+            let test_suite = quote! {
+                mod #tests_mod_ident {
+                    use super::*;
+
+                    #(#tests)*
+                }
+            };
+            test_suites.push(test_suite);
+        } else {
+            println!("Warning: not a directory: {:?}", sub_dir_path);
+        }
+    }
+
+    // generate main test_suites file
+    let test_suites = quote! {
+        use super::*;
+
+        #(#test_suites)*
+    };
+    let test_suites_file: File = syn::parse2(test_suites).unwrap();
+    let test_suites_file_contents = prettyplease::unparse(&test_suites_file);
+
+    Ok(ParserTestSuitesFile {
+        file_name: String::from("test_suites.rs"),
+        contents: test_suites_file_contents,
+    })
+}

examples/array_return.dm

@@ -0,0 +1,4 @@
+fn test()
+    println(42)
+    [0, 1, 2]
+end

examples/forty_two.dm

@@ -0,0 +1,3 @@
+fn main()
+    println(42)
+end

examples/hello_42.dm

@@ -0,0 +1,8 @@
+use std::core::println
+
+fn main(args: Array<String>)
+    let hello = 42
+    let world = hello + 16
+    println(hello)
+    println(world)
+end

examples/incompat.dm

@@ -0,0 +1,3 @@
+fn main()
+    let x = 1 + 2L
+end

examples/op_prec.dm

@@ -0,0 +1,4 @@
+fn main()
+    let n = 1 + 2 * 3 + 4
+    println(n)
+end

examples/op_prec.dvm_ir

@@ -0,0 +1,5 @@
+fn main() -> Void
+    $0 = 2 * 3
+    $1 = 1 + $0
+    $2 = $1 + 4
+    call std::core::println($2)

examples/worlds.dm

@@ -0,0 +1,19 @@
+class World(pub name: String, pub color: String) end
+
+fn getWorlds() -> List<World> = [
+    World('Mercury', 'Red'),
+    World('Earth', 'Blue'),
+    World('Jupiter', 'Orange')
+]
+
+fn findWorldByColor(worlds: List<World>, color: String) -> String
+    worlds.find { it -> it.color == color }
+        .map { it -> it.name }
+        .expect("No world has the given color ${color}")
+end
+
+fn main()
+    let worlds = getWorlds()
+    let blueWorld = findWorldByColor(worlds, 'Blue')
+    println("Hello, ${blueWorld}!")
+end

examples/worlds.dvm_ir

@@ -0,0 +1,89 @@
+struct World
+    pub String* name
+    pub String* color
+end
+
+void World::ctor(World *self, String* name, String* color)
+    self.name = move name
+    self.color = move color
+end
+
+const String %s0 = 'Mercury'
+const String %s1 = 'Red'
+const String %s2 = 'Earth'
+const String %s3 = 'Blue'
+const String %s4 = 'Jupiter'
+const String %s5 = 'Orange'
+
+List<World> *getWorlds()
+    List<World> *$0 = alloc std::list::ArrayList
+    call std::list::ArrayList::ctor($0)
+    World *$1 = alloc World
+    call World::ctor($1, %s0, %s1)
+    call std::list::ArrayList::add($0, $1)
+    World *$2 = alloc World
+    call World::ctor($2, %s2, %s3)
+    call std::list::ArrayList::add($0, $2)
+    World *$3 = alloc World
+    call World::ctor($3, %s4, %s5)
+    call std::list::ArrayList::add($0, $3)
+    ret $0
+end
+
+struct __findWorldByColor__cl0_captures
+    pub String* color
+end
+
+Boolean __findWorldByColor_cl0(__findWorldByColor__cl0_captures *__captures, World *it)
+    String *$0 = it.color
+    String *$1 = __captures.color
+    Boolean $2 = *$0 == *$1
+    ret $2
+end
+
+String* __findWorldByColor_cl1(World* it)
+    $0 = it.name
+    ret $0
+end
+
+
+String *findWorldByColor(List<World> *worlds, String *color)
+    __findWorldByColor__cl0_captures *$0 = alloc __findWorldByColor__cl0_captures
+    $0.color = color
+    Closure(__findWorldByColor__cl0_captures*)(World*)<Boolean> $1
+        = closure(__findWorldByColor_cl0, $0)
+    List<World> $2 = call std::list::ArrayList_impl_Find::find(worlds, $1)
+    Closure()(World*)<String*> $3 = closure(__findWorldByColor_cl1)
+    Option<String*> $4 = call std::list::ArrayList_impl_Monad($2, $3)
+
+    Display*[1] $5 = alloc Display[1]
+    $5[0] = color
+    DString *$6 = alloc DString
+    call DString::ctor($6, { }, $5)
+    String *$7 = call DString::toString($6)
+
+    String* $8 = call option::Option::expect($4, $7)
+
+    drop $0
+    drop $1
+    drop $2
+    drop $3
+    drop $5
+    drop $6
+
+    ret $8
+end
+
+const String %s7 = 'Blue'
+const String[2] %sa0 = { 'Hello, ', '!' }
+
+void main()
+    List<World> *$0 = call getWorlds()
+    World *$1 = call findWorldByColor($0, %s7)
+    Display[1] $2 = alloc Display[1]
+    $2[0] = move $1
+    std::string::DString *$3 = alloc std::string::DString
+    call std::string::DString::ctor($3, %sa0, $2)
+    String *$4 = call std::DString::toString($3)
+    call std::core::println($4)
+end

sketching/november_2025/json.dm

@@ -0,0 +1,211 @@
+ns jsonexample
+
+fn main()
+    let o: obj = match parseJsonObj('{ "a": { "b": { "c": [42] }} }')
+        Success(o) => o,
+        Failure(err) => panic!("There was an error during Json parsing: ${err}")
+    end
+    assertEq!(o.a.b.c[0], 42)
+end
+
+fn parseJsonObj(s: String) -> Result<obj, JsonParseError>
+    let lexer = JsonLexer(s)
+    let parser = JsonParser(lexer)
+    try
+        parser.object()
+    catch (parseError: JsonParseError)
+        Failure(parseError)
+    end
+end
+
+enum JsonToken
+    LBrace,
+    RBrace,
+    LSquare,
+    RSquare,
+    Comma,
+    String(String),
+    Number(Number),
+    Boolean(Boolean)
+end
+
+platform class String
+    pub fn <R> matchAt(startIndex: Int, matchers: Map<Regex, R | fn (match: String) -> R), opts: obj + { ignoreWhitespace: Boolean }) -> Option<R>
+        let slice: String = if opts.ignoreWhitespace then
+            /[\t\n\r ]*(<rest>.*)/.match(self[startIndex..]).rest as String
+        else
+            self[startIndex..]
+        end
+        for [regex, result] in matchers do
+            if regex.test(slice) is Some(match) then
+                if result is Fn then
+                    Some(result(match))
+                else
+                    Some(result)
+                end
+            end
+        end
+        None
+    end
+end
+
+platform class Regex
+
+    int RegexMatchBase
+        val match: String
+        val groups: [String],
+        val namedGroups: Map<String, String>
+    end
+
+    pub int RegexMatch
+        props!::<RegexMatchBase>()
+    end
+
+    platform fn doMatch(s) -> Option<RegexMatchBase>
+
+    pub fn match(s: String) -> Option<obj : RegexMatch>
+        doMatch(s).map { base ->
+            dyn obj {
+                ...base,
+                propertyMissing: { name: String ->
+                    base.namedGroups.get(name).unwrap()
+                }
+            }
+        }
+    end
+
+end
+
+class JsonLexer(val source: String)
+    var index: Int
+
+    fn matchCurrent() -> Option<JsonToken>
+        source.matchAt(index, [
+            /\{/ => JsonToken::LBrace,
+            /}/ => JsonToken::RBrace,
+            /\[/ => JsonToken::LSquare,
+            /]/ => JsonToken::RSquare,
+            /[0-9]+/ => { rawNumber: String => JsonToken::Number(number::parse(rawNumber))) }
+            /true/ => JsonToken::Boolean(true),
+            /false/ => JsonToken::False(false),
+            // The following is not a good way for matching strings but whatever
+            /"%w*"/ => { stringWithQuotes => JsonToken::String(stringWithQuotes[1..-1]) }
+        ], obj { ignoreWhitespace: true })
+    end
+
+    pub fn nextToken() -> Option<JsonToken>
+        matchCurrent().ifSome { token ->
+            match token
+                JsonToken::LBrace | JsonToken::RBrace | JsonToken::LSquare | JsonToken::RSquare | JsonToken::Comma => index++,
+                JsonToken::String(s) => index += s.len() + 2,
+                JsonToken::Number(n) => index += n.toString().len(),
+                JsonToken::Boolean(b) => match b
+                    true => index += 4,
+                    false => index += 5,
+                end
+            end
+        }
+    end
+
+    pub fn peek() -> Option<JsonToken> alias matchCurrent
+end
+
+class JsonParser(val lexer: JsonLexer)
+
+    macro parseError!($message)
+        throw JsonParserError($message)
+    end
+
+    macro expect!($tokenType)
+        match lexer.nextToken()
+            Some(token) => match token
+                JsonToken::$tokenType => do end,
+                _ => parseError!("Expected ${$tokenType}")
+            end,
+            _ => parseError!("Expected ${$tokenType}")
+        end
+    end
+
+    macro peek!($tokenType)
+        match lexer.peek()
+            Some(token) => match token
+                JsonToken::$tokenType => true,
+                _ => false
+            end,
+            None => false
+        end
+    end
+
+    pub fn object() -> obj
+        expect!(LBrace)
+        let result = obj {}
+        while keyValue() is Some((key, value)) do
+            result[key] = value
+        end
+        expect!(RBrace)
+        result
+    end
+
+    fn keyValue() -> Option<(String, Any)>
+        let key = match lexer.peek()
+            Some(token) => do
+                match token
+                    JsonToken::String(s) => s,
+                    _ => parseError!("Expected String")
+                end
+            end,
+            _ => do return None end
+        end
+        let value = value()
+        Some((key, value))
+    end
+
+    fn value() -> Any
+        match lexer.peek()
+            Some(token) => match token
+                JsonToken::LBrace => object(),
+                JsonToken::LSquare => array(),
+                _ => do
+                    match lexer.nextToken()
+                        JsonToken::String(s) => s,
+                        JsonToken::Number(n) => n,
+                        JsonToken::Boolean(b) => b,
+                        _ => parseError!("Expected String, Number, or Boolean")
+                    end
+                end
+            end,
+            None => parseError!("Expected LBrace, LSquare, String, Number, or Boolean")
+        end
+    end
+
+    fn array() -> [Any]
+        expect!(LSquare)
+        let results: List<Any> = []
+        while true do
+            match lexer.peek()
+                Some(token) => match token
+                    JsonToken::LBrace => results << object(),
+                    JsonToken::LSquare => results << array(),
+                    _ => do
+                        match lexer.nextToken()
+                            JsonToken::String(s) => results << s,
+                            JsonToken::Number(n) => results << n,
+                            JsonToken::Boolean(b) => results << b,
+                            _ => parseError!("Expected String, Number, or Boolean")
+                        end
+                    end
+                end,
+                None => panic! "Expected LBrace, LSquare, String, Number, or Boolean"
+            end
+            match lexer.nextToken()
+                Some(token) => match token
+                    JsonToken::Comma => continue,
+                    JsonToken::RSquare => break
+                end
+                _ => panic! "Expected Comma or RSquare"
+            end
+        end
+        expect!(RSquare)
+    end
+
+end

sketching/november_2025/rail.dm

@@ -0,0 +1,128 @@
+ns nr::train
+
+use object::{assign, Props, props!}
+
+pub int Train
+    name: String
+    primaryColor: Color
+
+    fld destination: String
+    fld volume: Int
+
+    fn blowHorn() -> IO
+end
+
+pub enum Color
+    White,
+    Blue,
+    Red
+end
+
+pub type Printer = fn (message: String) -> IO
+
+pub fn create(props: obj Props<Train> + { printer: Printer }) -> Train =
+    SimpleTrain(props).with {
+        volume = 80
+    }
+
+class SimpleTrain : Train
+    props!::<Train>()
+    printer: Printer
+
+    ctor(props: obj Props<Train> + { printer: Printer })
+        assign(self, props)
+    end
+
+    impl fn blowHorn() -> IO
+        printer("Train ${name} is blowing its horn at volume ${volume}!")
+    end
+end
+
+pub fn createViaObj(props: obj Props<Train>, printer: Printer) -> obj Train
+    obj {
+        ...props,
+        printer,
+        blowHorn: fn () -> IO
+            printer("Dynamic object Train ${train} is blowing its horn at volume ${self.volume}!")
+        end
+    }
+end
+
+// props lib file
+ns std::core::object
+
+pub fn assign(target: obj, source: obj)
+    for [key, value] source.props() do
+        target[key] = value
+    end
+end
+
+pub type Props<T> = obj {
+    [K in keyof T]: T[K]
+}
+
+pub macro fn <T> props!(_: TokenStream) -> TokenStream
+    let result = TokenStream()
+    for [key, type] in std::intrinsics::propsAndTypes::<T>() do
+        result << quote! {
+            #key: #type
+        }
+    end
+    result
+end
+
+// io lib file
+ns std::core
+
+pub enum IO<S : Stream = Stream, E = Error> : fn () -> IO<S, E>
+    Success(stream: S)
+        impl ()
+            try
+                doCall(stream)
+            catch (e: E)
+                Failure(e)
+            end
+        end
+    end,
+    Failure(_)
+        impl ()
+            self
+        end
+    end;
+
+    int
+        fn <Z : Stream = S> doCall(stream: S) -> IO<Z, E>
+    end
+end
+
+// main example file
+ns nr::example
+
+use nr::train::{create, createViaObj, Train, Color}
+
+fn main()
+    let train = create(obj {
+        name: 'Test Train',
+        primaryColor: Color::Blue,
+        destination: 'Nonavosa Central',
+        printer: println
+    })
+    train.blowHorn()
+    train.volume = 100
+    train.blowHorn()
+
+    let objTrain: obj Train = createViaObj(obj {
+        name: 'Obj Train',
+        primaryColor: Color::Red,
+        destination: 'Durandana',
+        printer: println
+    })
+    // Since it's an obj, we can dynamically add properties and override methods, similar to JS
+    objTrain.secondaryColor = Color::White
+    let originalBlowHorn = objTrain.blowHorn
+    objTrain.blowHorn = fn ()
+        originalBlowHorn()
+        println "Hello again! The train's colors are ${self.primaryColor} and ${self.secondaryColor}!"
+    end
+    objTrain.blowHorn()
+end

sketching/september_2025/adder/adder.dm

@@ -0,0 +1,5 @@
+use math::add
+
+fn main()
+    println add(1, 2) // 3
+end

sketching/september_2025/adder/math/add.dm

@@ -0,0 +1,3 @@
+mod math
+
+pub fn add(a: Int, b: Int) = a + b

sketching/september_2025/dll_rc/dll_rc.dm

@@ -0,0 +1,81 @@
+pub class Rc<T> : Drop, Copy
+
+    class Inner<T>(t: T)
+        mut count = 1
+    end
+
+    inner: &weak Inner = Null
+
+    pub ctor(t: T)
+        inner = Inner(t)
+    end
+
+    ctor(parent: &Self)
+        parent.inner++
+        inner = &weak parent.inner
+    end
+
+    pub fn copy() -> Self
+        Self(self)
+    end
+
+    impl fn drop(self)
+        if inner.upgrade() is Some(inner) then
+            inner.count--
+            if inner.count == 0 then
+                drop inner
+            end
+        else
+            throw Exception('rc.inner could not be converted from a weak reference')
+        end
+    end
+
+end
+
+class Game(player: Player) end
+
+class Player
+    pub mut game: &weak Game = Null
+end
+
+fn circular()
+    let player = Player()
+    let game = Game(player)
+
+    expectThrows(EmptyWeakReferenceException) {
+        player.game.upgrade()
+    }
+
+    player.game = &weak game
+
+    expectDoesNotThrow {
+        player.game.upgrade()
+    }
+end
+
+class Board
+    pub fn flip()
+        println 'Flipped!'
+    end
+end
+
+class ChessGame(pub board: rc Board) end
+
+class ChessPlayer(pub board: rc Board) end
+
+fn getGameAndPlayer() -> (ChessGame, ChessPlayer)
+    let board = rc Board() // Rc<Board> count is 1
+    let game = ChessGame(board) // Rc<Board> copied, count is 2
+    let player = ChessPlayer(board) // Rc<Board> copied, count is 3
+    (game, player) // initial Rc<Board> dropped before fn return, count now 2
+end
+
+fn playChess()
+    let (game, player) = getGameAndPlayer()
+    // Rc<Board> count is 2
+    let board = game.board // Copy, so count is now 3
+    board.flip()
+    drop board // count now 2
+    drop game // count now 1
+    drop player // count now 0, board memory finally dropped
+end

sketching/september_2025/hkt/functor.dm

@@ -0,0 +1,236 @@
+pub trait Functor[*T]
+    fn <U> map(ftu: fn (t: &*T) -> U) -> Self<U>
+end
+
+pub trait Functor[*L -> *R]
+    fn mapLeft(flr: fn (l: &*L) -> *R) -> Self<*L, *R>
+end
+
+pub enum Option<T>
+    Some(T),
+    None
+end
+
+pub enum Either<L, R>
+    Left(L),
+    Right(R)
+end
+
+pub impl Functor[*T] for Option<T>
+    fn <U> map(ftu: fn (t: &*T) -> U) -> Self<U>
+        if self is Some(t) then
+            Some(ftu(t))
+        else
+            None
+        end
+    end
+end
+
+pub impl Functor[*R] for Either<_, *R>
+    fn <U> map(f: fn (t: &*R) -> U) -> Self<_, U>
+        if self is Right(t) then
+            Right(f(t))
+        else
+            self
+        end
+    end
+end
+
+pub impl Functor[*L -> *R] for Either<L, R>
+    fn mapLeft(f: fn (l: &*L) -> *R) -> Self<*L, *R>
+        if self is Left(l) then
+            Right(f(l))
+        else
+            self
+        end
+    end
+end
+
+pub trait Monad[*T]
+    static fn lift(t: *T) -> Self<*T>
+    fn <U> flatMap(f: fn (t: &*T) -> Self<U>) -> Self<U>
+end
+
+pub trait Default
+    static fn default() -> Self
+end
+
+pub trait Empty[*T]
+    static fn empty() -> Self<*T>
+end
+
+pub trait Semigroup[*T]
+    type Other<*T>
+
+    fn concat(other: &Other<*T>) -> Self<&*T>
+    cons fn consConcat(other: Other<*T>) -> Self<*T>
+end
+
+pub int Iterable<T>
+    fn iter() -> Iterator<T> ref self
+    cons fn consIter() -> ConsIterator<T>
+end
+
+pub int Iterator<T>
+    fn next() -> Option<&T ref self>
+end
+
+pub int ConsIterator<T>
+    fn next() -> Option<T>
+end
+
+pub impl Semigroup[*T] for Iterable<*T>
+    type Other = Iterable<*T>
+
+    fn concat(other: &Other<*T>) -> Self<*T>
+        let result: Self<*T> = ArrayList(count())
+        for t in self do
+            result.add(t)
+        end
+        for t in other do
+            result.add(t)
+        end
+        result
+    end
+
+    cons fn consConcat(other: Other<*T>) -> Self<*T>
+        let result: Self<*T> = ArrayList(count())
+        for t in self do
+            result.add(t)
+        end
+        for t in other do
+            result.add(t)
+        end
+        result
+    end
+end
+
+pub int List<T> : Iterable<T>
+    fn add(t: T) -> Void
+end
+
+pub impl Functor[*T] for List<*T>
+    fn <U> map(f: (t: &*T) -> U) -> Self<U>
+        let mut result: Self<U> = ArrayList(count())
+        for t in self do
+            result.add(f(t))
+        end
+        result
+    end
+end
+
+pub impl Empty[*T] for List<*T>
+    static fn empty() -> List<*T> = ArrayList()
+end
+
+pub inst Monad[*T] for List<*T>
+    static fn lift(t: *T) -> List<*T>
+        let result: List<*T> = ArrayList()
+        result.add(t)
+        result
+    end
+
+    fn <U> flatMap(f: fn (t: &*T) -> List<U>) -> List<U>
+        let result: List<U> = ArrayList(count())
+        for t in self do
+            for u in f(t).consIter() do
+                result.add(u)
+            end
+        end
+        result
+    end
+end
+
+pub class ArrayList<T> : List<T>
+
+    let capacity: USize
+    let mut ts: Array<Option<T>>
+    let count: USize = 0
+
+    pub ctor(startCapacity: USize = 10)
+        capacity = startCapacity
+        ts = array(startCapacity, None)
+    end
+
+    class ArrayListIterator<T>(owner: &ArrayList<T>) /* ref owner (implied by constructor) */ : Iterator<T>
+        let i: USize = 0
+
+        impl fn next() -> Option<&T ref self>
+            if owner.ts[i] is Some(t) then
+                i++
+                Some(t)
+            else
+                None
+            end
+        end
+    end
+
+    class ConsArrayListIterator<T>(ts: Array<Option<T>>) : ConsIterator<T>
+        let i: USize = 0
+
+        impl fn next() -> Option<T>
+            if ts[i] is Some then
+                let wrappedT = mem::take(ts[i], None)
+                i++
+                wrappedT
+            else
+                None
+            end
+        end
+    end
+
+    impl fn iter() -> Iterator<&T> ref self
+        ArrayListIterator(&self)
+    end
+
+    impl cons fn consIter() -> Iterator<T>
+        ConsArrayListIterator(mem::take(ts, arrays::empty()))
+    end
+
+    impl fn add(t: T) -> Void
+        ts[count] = Some(t)
+        count++
+        if count == capacity then
+            resize()
+        end
+    end
+
+    fn resize() -> Void
+        let oldTs = mem::take(&ts, array(capacity * 2, None))
+        for (i, wrappedT) in oldTs.consIter() do
+            ts[i] = wrappedT
+        end
+    end
+
+end
+
+pub mod std::core
+
+    pub mod mem
+        pub native fn <T> take(target: &T, replacement: T) -> T
+    end
+
+    pub native fn <T> array(capacity: USize, init: fn () -> T) -> Array<T>
+
+    pub native fn <T> array(capacity: USize) -> Array<T> where T has Default
+
+    pub fn <T> list(...items: Array<T>) -> List<T>
+        let result = ArrayList(items.capacity())
+        for item in items.consIter() do
+            result.add(item)
+        end
+        result
+    end
+
+end
+
+// Other file
+use std::hkt::{Functor[List], Monad[List]}
+
+fn main()
+    let someNums: List<Int> = [1, 2, 3, 4, 5]
+    let plusOnes = someNums.map { it + 1 }
+    println plusOnes // 2, 3, 4, 5, 6
+    let twoOfEach = someNums.flatMap { [it, it] }
+    println twoOfEach // 1, 1, 2, 2, 3, 3, 4, 4, 5, 5
+end

sketching/september_2025/map/Map.dm

@@ -0,0 +1,198 @@
+pub trait Functor<T>[Self<T>]
+    fn map(mapper: fn (t: &T) -> U) -> Self<U>
+end
+
+pub trait Sum<T>
+    fn sum() -> T
+end
+
+pub trait Default
+    fn default() -> Self
+end
+
+pub trait Iter<T>
+    ref fn iter() -> Iterator<&T>
+end
+
+pub trait ConsIter<T>
+    cons fn consIter() -> Iterator<T>
+end
+
+pub int Iterator<T>
+    fn next() -> Option<T>
+end
+
+pub int List<T> impl Functor<T>, Iter<T>, ConsIter<T>
+    fn add(t: T) -> Void
+end
+
+pub class ArrayList<T> : List<T>
+    let mut currentIndex = 0
+    let mut inner: Array<T>
+
+    ctor(capacity: Int) where T impl Default
+        inner = Array(capacity, Default[T])
+    end
+
+    ctor(capacity: Int, init: fn () -> T)
+        inner = Array(capacity, init)
+    end
+
+    impl fn add(t: T) -> Void
+        inner[currentIndex] = t
+        let currentCapacity = inner.capacity()
+        currentIndex++
+        if currentIndex == currentCapacity then
+            let oldInner = std::mem::take(inner, Array(currentCapacity * 2))
+            arrays::copy(oldInner, inner)
+        end
+    end
+end
+
+impl Functor[ArrayList<*>]
+    fn map(mapper: fn (t: &T) -> U) -> Self<U>
+        let mut result: Array<U> = Array(inner.capacity)
+        for (i, t) in inner.iterWithIndex() do
+            result[i] = mapper(t)
+        end
+        result
+    end
+end
+
+impl Sum[Self = List<Int>, T = Int]
+    fn sum() -> Int
+        let mut result = 0
+        for value in self do
+            result += value
+        end
+        result
+    end
+end
+
+impl<T impl Default> Default[ArrayList<T>]
+    const DEFAULT_SIZE = 10
+
+    static fn default() -> Self = ArrayList(DEFAULT_SIZE, Default[T]::default)
+end
+
+impl<T> Iter[ArrayList<T>]
+    ref fn iter() -> Iterator<&T>
+        let mut currentIndex = 0
+        return {
+            if currentIndex < inner.count() then
+                let item = inner[currentIndex]
+                currentIndex++
+                Some(item)
+            else
+                None
+            end
+        }
+    end
+end
+
+impl<T impl Default> ConsIter[ArrayList<T>]
+    cons fn consIter() -> Iterator<T>
+        let mut currentIndex = 0
+        let inner = std::mem::take(inner, std::arrays::empty())
+        return |inner| {
+            if currentIndex < inner.count() then
+                let item = inner.take(currentIndex, Default[T]::default)
+                currentIndex++
+                Some(item)
+            else
+                None
+            end
+        }
+    end
+end
+
+pub enum Option<T>
+    Some(t: T),
+    None
+end
+
+impl Default[Option<*>]
+    static fn default() -> Self = None
+end
+
+pub trait HashCode
+    fn hash() -> USize
+end
+
+pub int Map<K, V>
+    fn get(key: K) -> Option<&V>
+    fn put(key: K, value: V) -> Void
+    fn take(key: K) -> Option<V>
+end
+
+pub class HashMap<K, V> : Map<K, V>
+    where K impl HashCode
+
+    const LOAD_FACTOR = 0.8
+
+    class Entry<K, V>(pub key: K, pub value: V) end
+
+    let mut buckets: List<List<Option<Entry<K, V>>>> = ArrayList(10)
+
+    fn getBucketIndex(key: K) -> Int
+        HashCode[K].hash(key) % buckets.size()
+    end
+
+    fn getCount() -> Int = buckets.map { it.count() }.sum::<Int>()
+
+    fn getCapacity() -> Int = buckets.map { it.capacity() }.sum::<Int>()
+
+    fn redistribute()
+        use std::mem::take
+        let oldBucketCapacity = buckets.first().unwrap().capacity()
+        let oldBuckets = take(buckets, ArrayList(oldBucketCapacity * 2))
+        for bucket in oldBuckets.consIter() do
+            for entry in bucket.consIter() do
+                let newIndex = getBucketIndex(entry.key)
+                let newBucket = buckets[newIndex]
+                newBucket.add(Entry(entry.key, entry.value))
+            end
+        end
+    end
+
+    impl fn put(key: K, value: V) -> Void
+        let bucket = buckets[getBucketIndex(key)]
+        bucket.add(Entry(key, value))
+        if getCount() / getCapacity() > LOAD_FACTOR then
+            redistribute()
+        end
+    end
+
+    impl fn get(key: K) -> Option<&V>
+        let bucket = buckets[getBucketIndex(key)] // bucket: &List<Entry<K, V>>
+        bucket.find { it.key == key } // it: &Entry<K, V>
+            .map { it.value } // it.value: &V
+    end
+
+    impl fn take(key: K) -> Option<V>
+        let mut bucket = buckets.take(getBucketIndex(key)) // bucket: List<Entry<K, V>>
+        if bucket.findIndex { it.key == key } is Some(index) then
+            let entry = bucket.take(index) // entry: Entry<K, V>
+            Some(entry.value) // moved out of Entry
+        else
+            None
+        end
+    end
+
+end
+
+impl HashCode for String
+    fn hash() -> Int = todo()
+end
+
+class Greeter(pub greeting: String) end
+
+fn main()
+    let greeterMap: Map<String, Greeter> = HashMap()
+    greeterMap.put("friendly", Greeter("Friendly hello!"))
+    greeterMap.put("nasty", Greeter("Nasty hello!"))
+    let friendlyGreeter: &Greeter = greeterMap.get("friendly").unwrap()
+    println friendlyGreeter.greeting
+    let nastyGreeter: Greeter = greeterMap.take("nasty").unwrap()
+    println nastyGreeter.greeting
+end

src/asm/assemble_ir.rs

@@ -0,0 +1,244 @@
+use crate::asm::{
+    AsmBinaryOperator, AsmFunction, AsmInstruction, AsmOperand, ControlUnit, ControlUnitId,
+    VirtualRegisterId,
+};
+use crate::ir::{
+    IrAssign, IrBinaryOperation, IrBinaryOperator, IrCall, IrCallType, IrExpression, IrFunction,
+    IrLiteral, IrReturn, IrStatement,
+};
+use std::collections::HashMap;
+use std::rc::Rc;
+
+struct AssemblyContext {
+    control_unit_counter: ControlUnitId,
+    control_units: Vec<ControlUnit>,
+    virtual_register_counter: VirtualRegisterId,
+    virtual_registers: HashMap<Rc<str>, VirtualRegisterId>,
+}
+
+impl AssemblyContext {
+    pub fn new() -> Self {
+        Self {
+            control_unit_counter: 0,
+            control_units: Vec::new(),
+            virtual_register_counter: 0,
+            virtual_registers: HashMap::new(),
+        }
+    }
+
+    fn next_control_unit_id(&mut self) -> ControlUnitId {
+        let id = self.control_unit_counter;
+        self.control_unit_counter += 1;
+        id
+    }
+
+    pub fn new_control_unit(&mut self) -> ControlUnitId {
+        let new_id = self.next_control_unit_id();
+        self.control_units.push(ControlUnit::new(new_id));
+        new_id
+    }
+
+    pub fn current_control_unit(&mut self) -> &ControlUnit {
+        if self.control_units.is_empty() {
+            self.new_control_unit();
+        }
+        self.control_units.last().unwrap()
+    }
+
+    pub fn current_control_unit_mut(&mut self) -> &mut ControlUnit {
+        if self.control_units.is_empty() {
+            self.new_control_unit();
+        }
+        self.control_units.last_mut().unwrap()
+    }
+
+    pub fn into_control_units(self) -> Vec<ControlUnit> {
+        self.control_units
+    }
+
+    pub fn get_virtual_register(&self, name: &str) -> VirtualRegisterId {
+        *self
+            .virtual_registers
+            .get(name)
+            .expect(&format!("Did not set a virtual register for name {}", name))
+    }
+
+    pub fn next_virtual_register(&mut self, name: &str) -> VirtualRegisterId {
+        if self.virtual_registers.contains_key(name) {
+            panic!(
+                "Should not already have a virtual register with name {}",
+                name
+            );
+        }
+        let virtual_register_id = self.virtual_register_counter;
+        self.virtual_register_counter += 1;
+        self.virtual_registers
+            .insert(name.into(), virtual_register_id);
+        virtual_register_id
+    }
+}
+
+pub fn assemble_ir_function(ir_function: &IrFunction) -> AsmFunction {
+    let mut context = AssemblyContext::new();
+
+    // body
+    for statement in ir_function.statements() {
+        assemble_ir_statement(statement, &mut context);
+    }
+
+    AsmFunction::new(ir_function.fqn().into(), context.into_control_units())
+}
+
+fn assemble_ir_statement(ir_statement: &IrStatement, context: &mut AssemblyContext) {
+    match ir_statement {
+        IrStatement::Allocate(_) => {
+            todo!()
+        }
+        IrStatement::Call(ir_call) => {
+            assemble_ir_call(ir_call, context);
+        }
+        IrStatement::Return(ir_return) => {
+            assemble_ir_return(ir_return, context);
+        }
+        IrStatement::Assign(ir_assign) => {
+            assemble_ir_assign(ir_assign, context);
+        }
+        IrStatement::MakeClosure(_) => {
+            todo!()
+        }
+        IrStatement::BinaryOperation(ir_binary_operation) => {
+            assemble_ir_binary_operation(ir_binary_operation, context)
+        }
+    }
+}
+
+fn assemble_ir_assign(ir_assign: &IrAssign, context: &mut AssemblyContext) {
+    let source_operand = match ir_assign.rhs() {
+        IrExpression::Variable(ir_variable) => {
+            let virtual_register_id = context.get_virtual_register(ir_variable.name());
+            AsmOperand::VirtualRegister(virtual_register_id)
+        }
+        IrExpression::Literal(ir_literal) => ir_literal_to_asm_operand(ir_literal),
+    };
+    let destination = context.next_virtual_register(ir_assign.lhs().name());
+    context
+        .current_control_unit_mut()
+        .append_instruction(AsmInstruction::Move {
+            source: source_operand,
+            destination,
+        })
+}
+
+fn ir_literal_to_asm_operand(ir_literal: &IrLiteral) -> AsmOperand {
+    match ir_literal {
+        IrLiteral::I8(i) => AsmOperand::I8(*i),
+        IrLiteral::I16(i) => AsmOperand::I16(*i),
+        IrLiteral::I32(i) => AsmOperand::I32(*i),
+        IrLiteral::I64(i) => AsmOperand::I64(*i),
+        IrLiteral::I128(i) => AsmOperand::I128(*i),
+        IrLiteral::ISize(i) => AsmOperand::ISize(*i),
+        IrLiteral::U8(u) => AsmOperand::U8(*u),
+        IrLiteral::U16(u) => AsmOperand::U16(*u),
+        IrLiteral::U32(u) => AsmOperand::U32(*u),
+        IrLiteral::U64(u) => AsmOperand::U64(*u),
+        IrLiteral::U128(u) => AsmOperand::U128(*u),
+        IrLiteral::USize(u) => AsmOperand::USize(*u),
+        IrLiteral::Boolean(b) => AsmOperand::Boolean(*b),
+        IrLiteral::Float(f) => AsmOperand::Float(*f),
+        IrLiteral::Double(d) => AsmOperand::Double(*d),
+        IrLiteral::String(s) => AsmOperand::String(s.clone()),
+    }
+}
+
+fn assemble_ir_call(ir_call: &IrCall, context: &mut AssemblyContext) {
+    // push args
+    for argument in ir_call.arguments() {
+        match argument {
+            IrExpression::Variable(ir_variable) => {
+                let variable_register_id = context.get_virtual_register(ir_variable.name());
+                context
+                    .current_control_unit_mut()
+                    .append_instruction(AsmInstruction::Push {
+                        source: AsmOperand::VirtualRegister(variable_register_id),
+                    })
+            }
+            IrExpression::Literal(ir_literal) => context
+                .current_control_unit_mut()
+                .append_instruction(AsmInstruction::Push {
+                    source: ir_literal_to_asm_operand(ir_literal),
+                }),
+        }
+    }
+    // issue call
+    match ir_call.call_type() {
+        IrCallType::Static => {
+            context
+                .current_control_unit_mut()
+                .append_instruction(AsmInstruction::InvokeStatic {
+                    fqn: ir_call.function_name_owned(),
+                });
+        }
+        IrCallType::Object => {
+            context
+                .current_control_unit_mut()
+                .append_instruction(AsmInstruction::InvokeObject {
+                    fqn: ir_call.function_name_owned(),
+                })
+        }
+        IrCallType::PlatformStatic => {}
+        IrCallType::PlatformObject => {}
+    }
+}
+
+fn assemble_ir_return(ir_return: &IrReturn, context: &mut AssemblyContext) {
+    let operand = ir_return.expression().map(|expression| {
+        match expression {
+            IrExpression::Variable(ir_variable) => {
+                let variable_virtual_register_id = context.get_virtual_register(ir_variable.name());
+                AsmOperand::VirtualRegister(variable_virtual_register_id)
+            }
+            IrExpression::Literal(ir_literal) => ir_literal_to_asm_operand(ir_literal),
+        }
+    });
+    context
+        .current_control_unit_mut()
+        .append_instruction(AsmInstruction::Return { operand });
+}
+
+fn assemble_ir_binary_operation(
+    ir_binary_operation: &IrBinaryOperation,
+    context: &mut AssemblyContext,
+) {
+    let left = match ir_binary_operation.left() {
+        IrExpression::Variable(ir_variable) => {
+            AsmOperand::VirtualRegister(context.get_virtual_register(ir_variable.name()))
+        }
+        IrExpression::Literal(ir_literal) => ir_literal_to_asm_operand(ir_literal),
+    };
+    let right = match ir_binary_operation.right() {
+        IrExpression::Variable(ir_variable) => {
+            AsmOperand::VirtualRegister(context.get_virtual_register(ir_variable.name()))
+        }
+        IrExpression::Literal(ir_literal) => ir_literal_to_asm_operand(ir_literal),
+    };
+    let destination = context.next_virtual_register(ir_binary_operation.destination().name());
+    let operator = match ir_binary_operation.operator() {
+        IrBinaryOperator::Add => AsmBinaryOperator::Add,
+        IrBinaryOperator::Subtract => AsmBinaryOperator::Subtract,
+        IrBinaryOperator::Multiply => AsmBinaryOperator::Multiply,
+        IrBinaryOperator::Divide => AsmBinaryOperator::Divide,
+        IrBinaryOperator::Exponent => {
+            todo!()
+        }
+    };
+
+    let instruction = AsmInstruction::BinaryOperation {
+        destination,
+        left,
+        right,
+        operator,
+    };
+    context
+        .current_control_unit_mut()
+        .append_instruction(instruction);
+}

src/asm/mod.rs

@@ -0,0 +1,256 @@
+pub mod assemble_ir;
+
+use std::fmt::{Display, Formatter};
+use std::rc::Rc;
+
+pub type ControlUnitId = usize;
+
+pub type VirtualRegisterId = u32;
+
+pub struct AsmFunction {
+    fqn: Rc<str>,
+    control_units: Vec<ControlUnit>,
+}
+
+impl AsmFunction {
+    pub fn new(fqn: Rc<str>, control_units: Vec<ControlUnit>) -> Self {
+        Self { fqn, control_units }
+    }
+}
+
+impl Display for AsmFunction {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        writeln!(f, "fn {}", self.fqn)?;
+        for control_unit in &self.control_units {
+            writeln!(f, "    #{}:", control_unit.id)?;
+            for instruction in &control_unit.instructions {
+                writeln!(f, "    {}", instruction)?;
+            }
+        }
+        Ok(())
+    }
+}
+
+pub struct ControlUnit {
+    id: ControlUnitId,
+    successor_ids: Vec<ControlUnitId>,
+    instructions: Vec<AsmInstruction>,
+}
+
+impl ControlUnit {
+    pub fn new(id: ControlUnitId) -> Self {
+        Self {
+            id,
+            successor_ids: vec![],
+            instructions: vec![],
+        }
+    }
+
+    pub fn append_instruction(&mut self, instruction: AsmInstruction) {
+        self.instructions.push(instruction);
+    }
+
+    pub fn append_instructions(&mut self, instructions: Vec<AsmInstruction>) {
+        self.instructions.extend(instructions);
+    }
+}
+
+pub enum AsmInstruction {
+    Goto {
+        control_unit_id: ControlUnitId,
+    },
+    Move {
+        source: AsmOperand,
+        destination: VirtualRegisterId,
+    },
+    Push {
+        source: AsmOperand,
+    },
+    Pop {
+        destination: VirtualRegisterId,
+    },
+    Allocate {
+        class_name: Rc<str>,
+        destination: VirtualRegisterId,
+    },
+    InvokeStatic {
+        fqn: Rc<str>,
+    },
+    InvokeObject {
+        fqn: Rc<str>,
+    },
+    InvokePlatformStatic {
+        fqn: Rc<str>,
+    },
+    InvokePlatformObject {
+        fqn: Rc<str>,
+    },
+    Return {
+        operand: Option<AsmOperand>,
+    },
+    BinaryOperation {
+        destination: VirtualRegisterId,
+        left: AsmOperand,
+        right: AsmOperand,
+        operator: AsmBinaryOperator,
+    },
+}
+
+impl Display for AsmInstruction {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        match self {
+            AsmInstruction::Goto { control_unit_id } => {
+                write!(f, "goto #{}", control_unit_id)
+            }
+            AsmInstruction::Move {
+                source,
+                destination,
+            } => {
+                write!(f, "move vr{}, {}", destination, source)
+            }
+            AsmInstruction::Push { source } => {
+                write!(f, "push {}", source)
+            }
+            AsmInstruction::Pop { destination } => {
+                write!(f, "pop vr{}", destination)
+            }
+            AsmInstruction::Allocate {
+                class_name,
+                destination,
+            } => {
+                write!(f, "allocate r{}, {}", destination, class_name)
+            }
+            AsmInstruction::InvokeStatic { fqn } => {
+                write!(f, "invoke_static {}", fqn)
+            }
+            AsmInstruction::InvokeObject { fqn } => {
+                write!(f, "invoke_object {}", fqn)
+            }
+            AsmInstruction::InvokePlatformStatic { fqn } => {
+                write!(f, "invoke_platform_static {}", fqn)
+            }
+            AsmInstruction::InvokePlatformObject { fqn } => {
+                write!(f, "invoke_platform_object {}", fqn)
+            }
+            AsmInstruction::Return { operand } => {
+                write!(f, "return")?;
+                if let Some(operand) = operand {
+                    write!(f, " {}", operand)?;
+                }
+                Ok(())
+            }
+            AsmInstruction::BinaryOperation {
+                destination,
+                left,
+                right,
+                operator,
+            } => {
+                write!(f, "op{} vr{}, {}, {}", operator, destination, left, right)
+            }
+        }
+    }
+}
+
+pub enum AsmOperand {
+    I8(i8),
+    I16(i16),
+    I32(i32),
+    I64(i64),
+    I128(i128),
+    ISize(isize),
+    U8(u8),
+    U16(u16),
+    U32(u32),
+    U64(u64),
+    U128(u128),
+    USize(usize),
+    Float(f32),
+    Double(f64),
+    Boolean(bool),
+    String(Rc<str>),
+    VirtualRegister(VirtualRegisterId),
+}
+
+impl Display for AsmOperand {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        match self {
+            AsmOperand::I8(i) => {
+                write!(f, "{}i8", i)
+            }
+            AsmOperand::I16(i) => {
+                write!(f, "{}i16", i)
+            }
+            AsmOperand::I32(i) => {
+                write!(f, "{}i32", i)
+            }
+            AsmOperand::I64(i) => {
+                write!(f, "{}i64", i)
+            }
+            AsmOperand::I128(i) => {
+                write!(f, "{}i128", i)
+            }
+            AsmOperand::ISize(i) => {
+                write!(f, "{}isize", i)
+            }
+            AsmOperand::U8(u) => {
+                write!(f, "{}u8", u)
+            }
+            AsmOperand::U16(u) => {
+                write!(f, "{}u16", u)
+            }
+            AsmOperand::U32(u) => {
+                write!(f, "{}u32", u)
+            }
+            AsmOperand::U64(u) => {
+                write!(f, "{}u64", u)
+            }
+            AsmOperand::U128(u) => {
+                write!(f, "{}u128", u)
+            }
+            AsmOperand::USize(u) => {
+                write!(f, "{}usize", u)
+            }
+            AsmOperand::Float(float) => {
+                write!(f, "{}f32", float)
+            }
+            AsmOperand::Double(d) => {
+                write!(f, "{}f64", d)
+            }
+            AsmOperand::Boolean(b) => {
+                write!(f, "{}", b)
+            }
+            AsmOperand::String(s) => {
+                write!(f, "{}", s)
+            }
+            AsmOperand::VirtualRegister(id) => {
+                write!(f, "vr{}", id)
+            }
+        }
+    }
+}
+
+pub enum AsmBinaryOperator {
+    Add,
+    Subtract,
+    Multiply,
+    Divide,
+}
+
+impl Display for AsmBinaryOperator {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        match self {
+            AsmBinaryOperator::Add => {
+                write!(f, "+")
+            }
+            AsmBinaryOperator::Subtract => {
+                write!(f, "-")
+            }
+            AsmBinaryOperator::Multiply => {
+                write!(f, "*")
+            }
+            AsmBinaryOperator::Divide => {
+                write!(f, "/")
+            }
+        }
+    }
+}

src/ast/build_tests/backtick_inner/greeting

@@ -0,0 +1 @@
+Hello, World!

src/ast/build_tests/backtick_string/mixed

@@ -0,0 +1 @@
+`Hello, ${world}!`

src/ast/build_tests/boolean_literal/false

@@ -0,0 +1 @@
+false

src/ast/build_tests/boolean_literal/true

@@ -0,0 +1 @@
+true

src/ast/mod.rs

@@ -1,6 +1,333 @@
-pub mod build;
-pub mod children;
-pub mod node;
-pub mod pretty_print;
-pub mod unparse;
-pub mod walk;
+pub mod node {
+    include!(concat!(env!("OUT_DIR"), "/src/ast/node.rs"));
+
+    impl OperatorInner {
+        pub fn name(&self) -> &'static str {
+            match self {
+                OperatorInner::Or => "op_or",
+                OperatorInner::And => "op_and",
+                OperatorInner::EqualTo => "op_eq",
+                OperatorInner::NotEqualTo => "op_neq",
+                OperatorInner::Greater => "op_gt",
+                OperatorInner::Less => "op_lt",
+                OperatorInner::GreaterEqual => "op_ge",
+                OperatorInner::LessEqual => "op_le",
+                OperatorInner::Add => "op_add",
+                OperatorInner::Subtract => "op_sub",
+                OperatorInner::Multiply => "op_mul",
+                OperatorInner::Divide => "op_div",
+                OperatorInner::Modulo => "op_mod",
+                OperatorInner::LeftShift => "op_ls",
+                OperatorInner::RightShift => "op_rs",
+                OperatorInner::Spread => "op_spread",
+                OperatorInner::Star => "op_star",
+                OperatorInner::Not => "op_not",
+                OperatorInner::Negative => "op_neg",
+                OperatorInner::PlusPlus => "op_pp",
+                OperatorInner::MinusMinus => "op_mm",
+                OperatorInner::CallOp => "op_call",
+                OperatorInner::Index => "op_index",
+            }
+        }
+    }
+
+    impl Expression {
+        pub fn analyzed_kind(&self) -> Kind {
+            match self {
+                Expression::Ternary(ternary_expression) => {
+                    todo!()
+                }
+                Expression::Or(or_expression) => {
+                    todo!()
+                }
+                Expression::And(and_expression) => {
+                    todo!()
+                }
+                Expression::Comparison(comparison_expression) => {
+                    todo!()
+                }
+                Expression::Shift(shift_expression) => {
+                    todo!()
+                }
+                Expression::Additive(additive_expression) => additive_expression
+                    .analyzed_kind()
+                    .expect("AdditiveExpression's analyzed_kind not set.")
+                    .clone(),
+                Expression::Multiplicative(multiplicative_expression) => {
+                    todo!()
+                }
+                Expression::Prefix(prefix_expression) => {
+                    todo!()
+                }
+                Expression::Suffix(suffix_expression) => {
+                    todo!()
+                }
+                Expression::Literal(literal) => literal.analyzed_kind(),
+                Expression::Identifier(identifier) => identifier
+                    .analyzed_kind()
+                    .expect("IdentifierExpression's analyzed_kind not set.")
+                    .clone(),
+                Expression::Fqn(fqn) => {
+                    todo!()
+                }
+                Expression::Closure(closure) => {
+                    todo!()
+                }
+                Expression::List(list_expression) => {
+                    todo!()
+                }
+            }
+        }
+    }
+
+    impl Literal {
+        pub fn analyzed_kind(&self) -> Kind {
+            match self {
+                Literal::IntLiteral(_) => Kind::Primitive(PrimitiveKind::Int.into()),
+                Literal::LongLiteral(_) => Kind::Primitive(PrimitiveKind::Long.into()),
+                Literal::DoubleLiteral(_) => Kind::Primitive(PrimitiveKind::Double.into()),
+                Literal::SingleQuoteString(_) => Kind::Primitive(PrimitiveKind::String.into()),
+                Literal::DString(_) => {
+                    todo!()
+                }
+                Literal::BacktickString(_) => {
+                    todo!()
+                }
+                Literal::BooleanLiteral(_) => Kind::Primitive(PrimitiveKind::Boolean.into()),
+            }
+        }
+    }
+
+    impl Default for Parameters {
+        fn default() -> Self {
+            Self::new(vec![])
+        }
+    }
+
+    impl Default for GenericParameters {
+        fn default() -> Self {
+            Self::new(Box::new(IdentifierList::new(vec![])))
+        }
+    }
+
+    impl Default for GenericArguments {
+        fn default() -> Self {
+            Self::new(Box::new(TypeUseList::new(vec![])))
+        }
+    }
+
+    impl Default for ImplementsList {
+        fn default() -> Self {
+            Self::new(vec![])
+        }
+    }
+
+    impl ReturnType {
+        pub fn void() -> Self {
+            Self::new(Box::new(TypeUse::PrimitiveType(PrimitiveType::Void)))
+        }
+    }
+
+    impl Default for ClassConstructor {
+        fn default() -> Self {
+            Self::new(vec![])
+        }
+    }
+
+    impl Default for ClosureParameters {
+        fn default() -> Self {
+            Self::new(vec![])
+        }
+    }
+}
+
+pub mod build {
+    use pest::iterators::Pairs;
+
+    include!(concat!(env!("OUT_DIR"), "/src/ast/build.rs"));
+
+    pub fn build_ast(file_id: usize, parsed_pairs: &mut Pairs<Rule>) -> CompilationUnit {
+        let compilation_unit_pair = parsed_pairs.next().unwrap();
+        build_compilation_unit(file_id, compilation_unit_pair)
+    }
+
+    #[cfg(test)]
+    mod build_tests {
+        use super::*;
+        use crate::ast::ast_node::AstNodeRef;
+        use crate::ast::pretty_print::PrettyPrint;
+        use crate::ast::walk::walk_depth_first;
+        use crate::parser::DeimosParser;
+        use crate::util::indent_writer::IndentWriter;
+        use pest::Parser;
+
+        fn parse(rule: Rule, input: &str) -> Pair<Rule> {
+            let parse_result = DeimosParser::parse(rule, input);
+            parse_result.expect("parsing failed").next().unwrap()
+        }
+
+        fn fmt_ast(node: &dyn PrettyPrint) -> String {
+            let mut acc = String::new();
+            let mut indent_writer = IndentWriter::new(0, "  ", &mut acc);
+            node.pretty_print(&mut indent_writer)
+                .expect("Pretty print failed");
+            acc
+        }
+
+        #[test]
+        fn boolean_literal_true() {
+            let pair = parse(
+                Rule::BooleanLiteral,
+                include_str!("build_tests/boolean_literal/true"),
+            );
+            assert_eq!(true, build_boolean_literal(0, pair));
+        }
+
+        #[test]
+        fn boolean_literal_false() {
+            let pair = parse(
+                Rule::BooleanLiteral,
+                include_str!("build_tests/boolean_literal/false"),
+            );
+            assert_eq!(false, build_boolean_literal(0, pair));
+        }
+
+        #[test]
+        fn backtick_inner_greeting() {
+            let pair = parse(
+                Rule::BacktickInner,
+                include_str!("build_tests/backtick_inner/greeting"),
+            );
+            assert_eq!("Hello, World!", build_backtick_inner(0, pair));
+        }
+
+        #[test]
+        fn backtick_string_mixed() {
+            let pair = parse(
+                Rule::BacktickString,
+                include_str!("build_tests/backtick_string/mixed"),
+            );
+            let backtick_string = build_backtick_string(0, pair);
+            assert_eq!(backtick_string.inners().count(), 2);
+            assert_eq!(backtick_string.expressions().count(), 1);
+        }
+
+        #[test]
+        fn d_string_expression_simple() {
+            let pair = parse(Rule::DStringExpression, "${thing}");
+            let d_string_expression = build_d_string_expression(0, pair);
+        }
+
+        #[test]
+        fn d_string_inner() {
+            let pair = parse(Rule::DStringInner, "Hello!");
+            let d_string_inner = build_d_string_inner(0, pair);
+            assert_eq!("Hello!", d_string_inner);
+        }
+
+        #[test]
+        fn d_string_mixed() {
+            let pair = parse(Rule::DString, "\"Hello, ${world}!\"");
+            let d_string = build_d_string(0, pair);
+            assert_eq!(d_string.inners().count(), 2);
+            assert_eq!(d_string.expressions().count(), 1);
+        }
+
+        #[test]
+        fn expression_simple_call() {
+            let pair = parse(Rule::Expression, "hello(42)");
+            let expression = build_expression(0, pair);
+        }
+
+        #[test]
+        fn multiple_expression_statements() {
+            let pair = parse(
+                Rule::Function,
+                "
+                fn test()
+                    println(42)
+                    println(43)
+                end
+                ",
+            );
+            let function = build_function(0, pair);
+
+            let mut number_of_statements = 0;
+
+            walk_depth_first(&function, &mut |node| match node {
+                AstNodeRef::Statement(_) => {
+                    number_of_statements += 1;
+                }
+                _ => {}
+            });
+
+            assert_eq!(2, number_of_statements, "Ast: {}", fmt_ast(&function));
+        }
+
+        #[test]
+        fn array_return_after_statement() {
+            let pair = parse(
+                Rule::Function,
+                "
+                fn test()
+                    println(42)
+                    [0, 1, 2]
+                end
+                ",
+            );
+            let function = build_function(0, pair);
+
+            let mut number_of_statements = 0;
+
+            walk_depth_first(&function, &mut |node| {
+                if let AstNodeRef::Statement(stmt) = node {
+                    number_of_statements += 1;
+                }
+            });
+
+            assert_eq!(2, number_of_statements);
+        }
+
+        #[test]
+        fn array_return_after_bare_identifier() {
+            // The following should parse as two expression statements
+            let pair = parse(
+                Rule::Function,
+                "
+                fn test()
+                    x
+                    [0, 1, 2]
+                end
+                ",
+            );
+            let function = build_function(0, pair);
+
+            let mut number_of_statements = 0;
+            walk_depth_first(&function, &mut |node| {
+                if let AstNodeRef::Statement(stmt) = node {
+                    number_of_statements += 1;
+                }
+            });
+
+            assert_eq!(2, number_of_statements);
+        }
+    }
+}
+
+pub mod pretty_print {
+    use crate::util::indent_writer::IndentWriter;
+
+    pub trait PrettyPrint {
+        fn pretty_print(&self, writer: &mut IndentWriter) -> std::fmt::Result;
+    }
+
+    include!(concat!(env!("OUT_DIR"), "/src/ast/pretty_print.rs"));
+}
+
+pub mod ast_node {
+    include!(concat!(env!("OUT_DIR"), "/src/ast/ast_node.rs"));
+}
+
+pub mod walk {
+    include!(concat!(env!("OUT_DIR"), "/src/ast/walk.rs"));
+}

src/ast/walk.rs

@@ -101,45 +101,45 @@ where
     f(node.as_node_ref());
 }
 
-#[cfg(test)]
-mod tests {
-    use crate::ast::build::build_ast;
-    use crate::ast::children::NodeRef;
-    use crate::ast::walk::walk_depth_first;
-    use crate::parser::{DeimosParser, Rule};
-    use indoc::indoc;
-    use pest::Parser;
-
-    #[test]
-    fn collect_identifiers() {
-        let parse_result = DeimosParser::parse(
-            Rule::CompilationUnit,
-            indoc! {"
-            ns greeter;
-            
-            class Greeter {}
-
-            fn main() {
-                let greeter = Greeter();
-            }
-        "},
-        );
-        match parse_result {
-            Ok(cu_pairs) => {
-                let cu = build_ast("greeter.dm", 0, cu_pairs.into_iter().next().unwrap());
-                let mut identifier_count = 0;
-                walk_depth_first(&cu, &mut |node_ref| match node_ref {
-                    NodeRef::Identifier(identifier) => {
-                        dbg!(identifier);
-                        identifier_count += 1;
-                    }
-                    _ => {}
-                });
-                assert_eq!(identifier_count, 5);
-            }
-            Err(err) => {
-                panic!("{}", err);
-            }
-        }
-    }
-}
+// #[cfg(test)]
+// mod tests {
+//     use crate::ast::build::build_ast;
+//     use crate::ast::children::NodeRef;
+//     use crate::ast::walk::walk_depth_first;
+//     use crate::parser::{DeimosParser, Rule};
+//     use indoc::indoc;
+//     use pest::Parser;
+// 
+//     #[test]
+//     fn collect_identifiers() {
+//         let parse_result = DeimosParser::parse(
+//             Rule::CompilationUnit,
+//             indoc! {"
+//             ns greeter;
+//             
+//             class Greeter {}
+// 
+//             fn main() {
+//                 let greeter = Greeter();
+//             }
+//         "},
+//         );
+//         match parse_result {
+//             Ok(cu_pairs) => {
+//                 let cu = build_ast("greeter.dm", 0, cu_pairs.into_iter().next().unwrap());
+//                 let mut identifier_count = 0;
+//                 walk_depth_first(&cu, &mut |node_ref| match node_ref {
+//                     NodeRef::Identifier(identifier) => {
+//                         dbg!(identifier);
+//                         identifier_count += 1;
+//                     }
+//                     _ => {}
+//                 });
+//                 assert_eq!(identifier_count, 5);
+//             }
+//             Err(err) => {
+//                 panic!("{}", err);
+//             }
+//         }
+//     }
+// }

src/bin/dmc/cst.rs

@@ -0,0 +1,30 @@
+use deimos::parser::{DeimosParser, Rule};
+use std::path::PathBuf;
+use pest::iterators::{Pair, Pairs};
+use pest::Parser;
+
+fn print_pair(pair: Pair<Rule>) {
+    println!("{:?}", pair.as_rule());
+    println!("{:?}", pair.as_span());
+    println!("----");
+    print_pairs(pair.into_inner());
+}
+
+fn print_pairs(pairs: Pairs<Rule>) {
+    for pair in pairs {
+        print_pair(pair);
+    }
+}
+
+pub fn show_cst(path: &PathBuf) {
+    let src = std::fs::read_to_string(path).unwrap();
+    let parse_result = DeimosParser::parse(Rule::CompilationUnit, &src);
+    match parse_result {
+        Ok(pairs) => {
+            print_pairs(pairs);
+        }
+        Err(error) => {
+            eprintln!("{:?}", error);
+        }
+    }
+}

src/bin/dmc/ir.rs

@@ -0,0 +1,146 @@
+use codespan_reporting::files::SimpleFiles;
+use codespan_reporting::term;
+use codespan_reporting::term::termcolor::{ColorChoice, StandardStream};
+use deimos::asm::assemble_ir::assemble_ir_function;
+use deimos::ast::build::build_ast;
+use deimos::ast::node::CompilationUnit;
+use deimos::ir::lower_ast::lower_compilation_unit;
+use deimos::ir::Ir;
+use deimos::name_analysis::analyze_names;
+use deimos::name_analysis::symbol_table::SymbolTable;
+use deimos::parser::{DeimosParser, Rule};
+use deimos::std_core::add_std_core_symbols;
+use deimos::type_analysis::analyze_types;
+use pest::Parser;
+use std::collections::HashMap;
+use std::fmt::{Debug, Display, Formatter};
+use std::path::PathBuf;
+
+struct ParseErrors {
+    errors: Vec<pest::error::Error<Rule>>,
+}
+
+impl Debug for ParseErrors {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        Display::fmt(self, f)
+    }
+}
+
+impl Display for ParseErrors {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        writeln!(f, "There were errors during parsing.")?;
+        for parse_error in &self.errors {
+            writeln!(f, "{}", parse_error)?;
+        }
+        Ok(())
+    }
+}
+
+impl std::error::Error for ParseErrors {}
+
+#[derive(Debug)]
+struct CompilationErrors {
+    count: usize,
+}
+
+impl Display for CompilationErrors {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        if self.count == 1 {
+            writeln!(f, "There was 1 error during compilation. See above.")
+        } else {
+            writeln!(
+                f,
+                "There were {} errors during compilation. See above.",
+                self.count
+            )
+        }
+    }
+}
+
+impl std::error::Error for CompilationErrors {}
+
+pub fn compile_to_ir(
+    paths: &[PathBuf],
+) -> Result<Vec<CompilationUnit>, Box<dyn std::error::Error>> {
+    let mut paths_and_sources: HashMap<String, String> = HashMap::new();
+    for path in paths {
+        let src = std::fs::read_to_string(path).unwrap();
+        paths_and_sources.insert(path.display().to_string(), src);
+    }
+
+    let mut compilation_units = vec![];
+    let mut files: SimpleFiles<&str, &str> = SimpleFiles::new();
+    let mut parse_errors = vec![];
+
+    for (path, source) in &paths_and_sources {
+        let parse_result = DeimosParser::parse(Rule::CompilationUnit, source);
+        match parse_result {
+            Ok(mut pairs) => {
+                let file_id = files.add(path, source);
+                let compilation_unit = build_ast(file_id, &mut pairs);
+                compilation_units.push(compilation_unit);
+            }
+            Err(error) => {
+                parse_errors.push(error);
+            }
+        }
+    }
+
+    if !parse_errors.is_empty() {
+        return Err(Box::new(ParseErrors {
+            errors: parse_errors,
+        }));
+    }
+
+    let mut symbol_table = SymbolTable::new();
+    add_std_core_symbols(&mut symbol_table).expect("Failed to add std::core symbols.");
+
+    let name_diagnostics = analyze_names(&mut compilation_units, &files, &mut symbol_table);
+
+    if name_diagnostics.is_empty() {
+        println!("Name analysis complete.");
+    } else {
+        let writer = StandardStream::stderr(ColorChoice::Always);
+        let config = term::Config::default();
+        for diagnostic in &name_diagnostics {
+            term::emit(&mut writer.lock(), &config, &files, diagnostic)?;
+        }
+        return Err(Box::new(CompilationErrors {
+            count: name_diagnostics.len(),
+        }));
+    }
+
+    let type_diagnostics = analyze_types(&mut compilation_units);
+
+    if type_diagnostics.is_empty() {
+        println!("Type analysis complete.");
+    } else {
+        let writer = StandardStream::stderr(ColorChoice::Always);
+        let config = term::Config::default();
+        for diagnostic in &type_diagnostics {
+            term::emit(&mut writer.lock(), &config, &files, &diagnostic)?;
+        }
+        return Err(Box::new(CompilationErrors {
+            count: type_diagnostics.len(),
+        }));
+    }
+
+    for compilation_unit in &compilation_units {
+        let cu_irs = lower_compilation_unit(compilation_unit);
+        for ir in &cu_irs {
+            println!("{}", ir)
+        }
+
+        for ir in &cu_irs {
+            match ir {
+                Ir::Function(ir_function) => {
+                    let asm_function = assemble_ir_function(ir_function);
+                    println!("{}", asm_function);
+                }
+                _ => {}
+            }
+        }
+    }
+
+    Ok(compilation_units)
+}

src/bin/dmc/main.rs

@@ -1,12 +1,16 @@
+mod cst;
+mod ir;
 mod name_analysis;
 mod p3;
-mod unparse;
+// mod unparse;
 
 use std::path::PathBuf;
 
+// use crate::unparse::unparse;
+use crate::cst::show_cst;
+use crate::ir::compile_to_ir;
 use crate::name_analysis::name_analysis;
 use crate::p3::pretty_print_parse;
-use crate::unparse::unparse;
 use clap::{Parser, Subcommand};
 
 #[derive(Debug, Parser)]
@@ -19,35 +23,35 @@ struct Cli {
 
 #[derive(Debug, Subcommand)]
 enum Commands {
-    #[command(arg_required_else_help = true)]
-    Unparse {
-        paths: Vec<PathBuf>,
-    },
-    P3 {
-        paths: Vec<PathBuf>,
-    },
-    NameAnalysis {
-        paths: Vec<PathBuf>,
-    },
+    Cst { paths: Vec<PathBuf> },
+    P3 { paths: Vec<PathBuf> },
+    NameAnalysis { paths: Vec<PathBuf> },
+    Ir { paths: Vec<PathBuf> },
 }
 
 fn main() {
     let args = Cli::parse();
     match args.command {
-        Commands::Unparse { paths } => {
-            for path in paths {
-                unparse(&path);
+        Commands::Cst { paths } => {
+            for path in &paths {
+                show_cst(path);
             }
         }
         Commands::P3 { paths } => {
             for path in paths {
-                pretty_print_parse(&path)
+                pretty_print_parse(&path);
             }
         }
         Commands::NameAnalysis { paths } => {
             let result = name_analysis(&paths);
             if let Err(e) = result {
-                eprintln!("{}", e)
+                eprintln!("{}", e);
+            }
+        }
+        Commands::Ir { paths } => {
+            let result = compile_to_ir(&paths);
+            if let Err(e) = result {
+                eprintln!("{}", e);
             }
         }
     }

src/bin/dmc/name_analysis.rs

@@ -5,37 +5,73 @@ use deimos::ast::build::build_ast;
 use deimos::name_analysis::analyze_names;
 use deimos::name_analysis::symbol_table::SymbolTable;
 use deimos::parser::{DeimosParser, Rule};
-use pest::Parser;
-use std::path::PathBuf;
 use deimos::std_core::add_std_core_symbols;
+use pest::Parser;
+use std::collections::HashMap;
+use std::fmt::{Debug, Display, Formatter};
+use std::path::PathBuf;
+use deimos::ast::node::CompilationUnit;
 
-pub fn name_analysis(paths: &Vec<PathBuf>) -> Result<(), Box<dyn std::error::Error>> {
-    let mut compilation_units = vec![];
-    let mut files = SimpleFiles::new();
-    
+struct ParseErrors {
+    errors: Vec<pest::error::Error<Rule>>,
+}
+
+impl Debug for ParseErrors {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        Display::fmt(self, f)
+    }
+}
+
+impl Display for ParseErrors {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        writeln!(f, "There were errors during parsing.")?;
+        for parse_error in &self.errors {
+            writeln!(f, "{}", parse_error)?;
+        }
+        Ok(())
+    }
+}
+
+impl std::error::Error for ParseErrors {}
+
+pub fn name_analysis(paths: &[PathBuf]) -> Result<Vec<CompilationUnit>, Box<dyn std::error::Error>> {
+    let mut paths_and_sources: HashMap<String, String> = HashMap::new();
     for path in paths {
         let src = std::fs::read_to_string(path).unwrap();
-        let parse_result = DeimosParser::parse(Rule::CompilationUnit, &src);
-        let file_id = files.add(path.display().to_string(), src.clone()); // I don't love this clone
+        paths_and_sources.insert(path.display().to_string(), src);
+    }
 
+    let mut compilation_units = vec![];
+    let mut files: SimpleFiles<&str, &str> = SimpleFiles::new();
+    let mut parse_errors = vec![];
+
+    for (path, source) in &paths_and_sources {
+        let parse_result = DeimosParser::parse(Rule::CompilationUnit, source);
         match parse_result {
             Ok(mut pairs) => {
-                let compilation_unit_pair = pairs.next().unwrap();
-                let compilation_unit = build_ast(&path.display().to_string(), file_id, compilation_unit_pair);
+                let file_id = files.add(path, source);
+                let compilation_unit = build_ast(file_id, &mut pairs);
                 compilation_units.push(compilation_unit);
-                Ok::<(), Box<dyn std::error::Error>>(())
             }
-            Err(e) => Err(e.into()),
-        }?;
+            Err(error) => {
+                parse_errors.push(error);
+            }
+        }
+    }
+
+    if !parse_errors.is_empty() {
+        return Err(Box::new(ParseErrors {
+            errors: parse_errors,
+        }));
     }
 
     let mut symbol_table = SymbolTable::new();
     add_std_core_symbols(&mut symbol_table).expect("Failed to add std::core symbols.");
-    
-    let diagnostics = analyze_names(&mut compilation_units, &mut symbol_table);
+
+    let diagnostics = analyze_names(&mut compilation_units, &files, &mut symbol_table);
     if diagnostics.is_empty() {
         println!("Name analysis complete.");
-        println!("Symbol table\n-------\n{}", symbol_table);
+        println!("{}", symbol_table);
     } else {
         let writer = StandardStream::stderr(ColorChoice::Always);
         let config = term::Config::default();
@@ -43,6 +79,6 @@ pub fn name_analysis(paths: &Vec<PathBuf>) -> Result<(), Box<dyn std::error::Err
             term::emit(&mut writer.lock(), &config, &files, &diagnostic)?;
         }
     }
-    
-    Ok(())
+
+    Ok(compilation_units)
 }

src/bin/dmc/p3.rs

@@ -10,12 +10,13 @@ pub fn pretty_print_parse(path: &PathBuf) {
     let parse_result = DeimosParser::parse(Rule::CompilationUnit, &src);
     match parse_result {
         Ok(mut pairs) => {
-            let compilation_unit_pair = pairs.next().unwrap();
-            let compilation_unit = build_ast(&path.display().to_string(), 0, compilation_unit_pair);
-            let mut indent_writer = IndentWriter::new(0, "  ", Box::new(std::io::stdout()));
+            let compilation_unit = build_ast(0, &mut pairs);
+            let mut acc = String::new();
+            let mut indent_writer = IndentWriter::new(0, "  ", &mut acc);
             compilation_unit
                 .pretty_print(&mut indent_writer)
                 .expect("Unable to pretty-print.");
+            println!("{}", acc);
         }
         Err(e) => {
             eprintln!("{}", e);