diff --git a/ast-generator/src/build_fn/leaf_enum_build_fn.rs b/ast-generator/src/build_fn/leaf_enum_build_fn.rs
index 7844a54..b97f0a8 100644
--- a/ast-generator/src/build_fn/leaf_enum_build_fn.rs
+++ b/ast-generator/src/build_fn/leaf_enum_build_fn.rs
@@ -19,7 +19,7 @@ pub fn make_leaf_enum_build_fn(leaf_enum_build_spec: &LeafEnumBuildSpec) -> Toke
         .collect::<Vec<_>>();
 
     quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        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,)*
diff --git a/ast-generator/src/build_fn/leaf_struct_build_fn.rs b/ast-generator/src/build_fn/leaf_struct_build_fn.rs
index 5bdabb3..93a32f1 100644
--- a/ast-generator/src/build_fn/leaf_struct_build_fn.rs
+++ b/ast-generator/src/build_fn/leaf_struct_build_fn.rs
@@ -18,6 +18,22 @@ pub fn make_leaf_struct_build_fn(build_spec: &LeafStructBuildSpec) -> TokenStrea
                         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<_>>();
@@ -28,7 +44,7 @@ pub fn make_leaf_struct_build_fn(build_spec: &LeafStructBuildSpec) -> TokenStrea
         .collect::<Vec<_>>();
 
     quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
             #(#child_builders;)*
             #return_type_ident::new(
                 #(#child_args,)*
diff --git a/ast-generator/src/build_fn/node_production_build_fn.rs b/ast-generator/src/build_fn/node_production_build_fn.rs
index c315674..0cab792 100644
--- a/ast-generator/src/build_fn/node_production_build_fn.rs
+++ b/ast-generator/src/build_fn/node_production_build_fn.rs
@@ -10,9 +10,9 @@ pub fn make_node_production_build_fn(spec: &NodeProductionBuildSpec) -> TokenStr
     let inner_build_fn_ident = format_ident!("{}", spec.with());
     
     quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        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(inner_pair)
+            #inner_build_fn_ident(file_id, inner_pair)
         }
     }
 }
\ No newline at end of file
diff --git a/ast-generator/src/build_fn/polymorphic_enum_loop_build_fn.rs b/ast-generator/src/build_fn/polymorphic_enum_loop_build_fn.rs
index bcde9d4..0e57697 100644
--- a/ast-generator/src/build_fn/polymorphic_enum_loop_build_fn.rs
+++ b/ast-generator/src/build_fn/polymorphic_enum_loop_build_fn.rs
@@ -12,7 +12,7 @@ fn make_pass_through(pass_through: &PolymorphicEnumLoopRulePassThrough) -> Token
     let inner_build_fn_ident = format_ident!("{}", pass_through.with());
     quote! {
         Rule::#rule_ident => {
-            result = Some(#inner_build_fn_ident(inner_pair))
+            result = Some(#inner_build_fn_ident(file_id, inner_pair))
         }
     }
 }
@@ -20,7 +20,7 @@ fn make_pass_through(pass_through: &PolymorphicEnumLoopRulePassThrough) -> Token
 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(inner_pair))
+        Box::new(#child_build_fn_ident(file_id, inner_pair))
     }
 }
 
@@ -93,7 +93,7 @@ pub fn make_polymorphic_enum_loop_build_fn(spec: &PolymorphicEnumLoopBuildSpec)
         .collect::<Vec<_>>();
 
     quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
             let mut result: Option<#return_type_ident> = None;
             for inner_pair in #iter_expr {
                 match inner_pair.as_rule() {
diff --git a/ast-generator/src/build_fn/polymorphic_pass_through_build_fn.rs b/ast-generator/src/build_fn/polymorphic_pass_through_build_fn.rs
index 6a61699..31682bc 100644
--- a/ast-generator/src/build_fn/polymorphic_pass_through_build_fn.rs
+++ b/ast-generator/src/build_fn/polymorphic_pass_through_build_fn.rs
@@ -1,5 +1,7 @@
 use crate::deserialize::util::{make_build_fn_name, make_build_pair};
-use crate::spec::polymorphic_pass_through_spec::{PolymorphicPassThroughBuildSpec, PolymorphicPassThroughVariant};
+use crate::spec::polymorphic_pass_through_spec::{
+    PolymorphicPassThroughBuildSpec, PolymorphicPassThroughVariant,
+};
 use proc_macro2::TokenStream;
 use quote::{format_ident, quote};
 
@@ -9,37 +11,36 @@ pub fn make_polymorphic_pass_through_build_fn(
     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(inner_pair)
-                            )
-                        }
+
+    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(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(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        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,)*
diff --git a/ast-generator/src/build_fn/polymorphic_type_build_fn.rs b/ast-generator/src/build_fn/polymorphic_type_build_fn.rs
index 1702fac..657f85e 100644
--- a/ast-generator/src/build_fn/polymorphic_type_build_fn.rs
+++ b/ast-generator/src/build_fn/polymorphic_type_build_fn.rs
@@ -10,9 +10,9 @@ pub fn make_polymorphic_type_build_fn(build_spec: &PolymorphicTypeBuildSpec) ->
     let inner_build_fn_ident = format_ident!("{}", make_build_fn_name(build_spec.kind()));
 
     quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        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(inner_pair)
+            #inner_build_fn_ident(file_id, inner_pair)
         }
     }
 }
diff --git a/ast-generator/src/build_fn/production_build_fn.rs b/ast-generator/src/build_fn/production_build_fn.rs
index 4bd4b78..4f8c2e8 100644
--- a/ast-generator/src/build_fn/production_build_fn.rs
+++ b/ast-generator/src/build_fn/production_build_fn.rs
@@ -80,7 +80,7 @@ pub fn make_production_build_fn(production_build_spec: &ProductionBuildSpec) ->
     };
 
     quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
             #pair_mapper
         }
     }
diff --git a/ast-generator/src/build_fn/struct_build_fn.rs b/ast-generator/src/build_fn/struct_build_fn.rs
index 92ee6b5..2f35b6a 100644
--- a/ast-generator/src/build_fn/struct_build_fn.rs
+++ b/ast-generator/src/build_fn/struct_build_fn.rs
@@ -56,13 +56,13 @@ fn make_vec_child_match_action(vec_child: &VecChild) -> TokenStream {
         VecChildBuild::String(string_build) => {
             let build_fn_ident = format_ident!("{}", string_build.with());
             quote! {
-                #child_name_ident.push(#build_fn_ident(inner_pair))
+                #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(inner_pair)))
+                #child_name_ident.push(Box::new(#build_fn_ident(file_id, inner_pair)))
             }
         }
     }
@@ -72,7 +72,7 @@ fn make_node_member_child_match_action(name: &str, node_child: &NodeMemberBuild)
     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(inner_pair)))
+        #child_name_ident = Some(Box::new(#build_fn_ident(file_id, inner_pair)))
     }
 }
 
@@ -204,7 +204,7 @@ pub fn make_struct_build_fn(build_spec: &StructSpec) -> TokenStream {
     let new_stream = make_return_value_stream(build_spec);
 
     quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        fn #build_fn_ident(file_id: usize, #pair_ident: Pair<Rule>) -> #return_type_ident {
             #(#child_holders;)*
 
             #iter_stream
diff --git a/ast-generator/src/build_fn/tree_enum_build_fn.rs b/ast-generator/src/build_fn/tree_enum_build_fn.rs
index f661d06..323dbf2 100644
--- a/ast-generator/src/build_fn/tree_enum_build_fn.rs
+++ b/ast-generator/src/build_fn/tree_enum_build_fn.rs
@@ -17,27 +17,27 @@ pub fn make_enum_build_fn(enum_build_spec: &TreeEnumBuildSpec) -> TokenStream {
                     EnumRuleChildKind::Node(node_child) => {
                         let inner_build_fn_ident =
                             format_ident!("{}", node_child.with());
-                        quote! { #inner_build_fn_ident(inner_pair) }
+                        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(inner_pair) }
+                        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(inner_pair) }
+                        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(inner_pair) }
+                        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(inner_pair) }
+                        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(inner_pair) }
+                        quote! { #inner_build_fn_ident(file_id, inner_pair) }
                     }
                 };
                 quote! {
@@ -52,7 +52,7 @@ pub fn make_enum_build_fn(enum_build_spec: &TreeEnumBuildSpec) -> TokenStream {
         .collect::<Vec<_>>();
 
     quote! {
-        fn #build_fn_ident(#pair_ident: Pair<Rule>) -> #return_type_ident {
+        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,)*
diff --git a/ast-generator/src/deserialize/leaf_struct_spec.rs b/ast-generator/src/deserialize/leaf_struct_spec.rs
index 5243eed..0b2c78c 100644
--- a/ast-generator/src/deserialize/leaf_struct_spec.rs
+++ b/ast-generator/src/deserialize/leaf_struct_spec.rs
@@ -2,8 +2,14 @@ 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) -> LeafStructMember {
-    LeafStructMember::new(member_name, LeafStructMemberKind::String)
+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 {
@@ -12,8 +18,8 @@ pub fn deserialize_leaf_struct(name: &str, props: &Yaml) -> LeafStructBuildSpec
         .unwrap()
         .iter()
         .map(|member_hash| {
-            let (member_name, _props) = unwrap_single_member_hash(member_hash);
-            deserialize_member(&member_name)
+            let (member_name, props) = unwrap_single_member_hash(member_hash);
+            deserialize_member(&member_name, props)
         })
         .map(Box::new)
         .collect();
diff --git a/ast-generator/src/lib.rs b/ast-generator/src/lib.rs
index ff1281a..841ad3c 100644
--- a/ast-generator/src/lib.rs
+++ b/ast-generator/src/lib.rs
@@ -85,12 +85,10 @@ fn generate_build_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
         .collect::<Vec<_>>();
 
     let combined = quote! {
-        //noinspection RsUnusedImport
         use crate::parser::Rule;
-        //noinspection RsUnusedImport
         use pest::iterators::Pair;
-        //noinspection RsUnusedImport
         use crate::ast::node::*;
+        use std::range::Range;
 
         #(#build_fns)*
     };
@@ -108,6 +106,8 @@ fn generate_node_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
         .filter(Option::is_some)
         .collect::<Vec<_>>();
     let combined = quote! {
+        use std::range::Range;
+        
         #(#types)*
     };
     AstGeneratedFile {
diff --git a/ast-generator/src/pretty_print.rs b/ast-generator/src/pretty_print.rs
index 1bfbf2d..c2eea13 100644
--- a/ast-generator/src/pretty_print.rs
+++ b/ast-generator/src/pretty_print.rs
@@ -1,5 +1,8 @@
 use crate::spec::leaf_enum_spec::LeafEnumBuildSpec;
 use crate::spec::leaf_struct_spec::{LeafStructBuildSpec, LeafStructMemberKind};
+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};
@@ -7,28 +10,25 @@ use crate::spec::BuildSpec;
 use convert_case::{Case, Casing};
 use proc_macro2::TokenStream;
 use quote::{format_ident, quote};
-use crate::spec::polymorphic_enum_loop_spec::{PolymorphicEnumLoopBuildSpec, PolymorphicEnumLoopRule, PolymorphicEnumLoopRuleBuildChild};
 
 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
-            }
+
+    let build = spec
+        .rules()
+        .find(|rule| match rule {
+            PolymorphicEnumLoopRule::Build(_) => true,
+            _ => false,
         })
-        .map(|rule| {
-            match rule {
-                PolymorphicEnumLoopRule::Build(build) => build,
-                _ => unreachable!()
-            }
+        .map(|rule| match rule {
+            PolymorphicEnumLoopRule::Build(build) => build,
+            _ => unreachable!(),
         })
         .unwrap();
-    
-    let child_print_statements = build.children()
+
+    let child_print_statements = build
+        .children()
         .map(|child| {
             let child_ident = match child {
                 PolymorphicEnumLoopRuleBuildChild::UseCurrent(use_current) => {
@@ -43,7 +43,7 @@ fn make_polymorphic_enum_loop_p2_impl(spec: &PolymorphicEnumLoopBuildSpec) -> To
             }
         })
         .collect::<Vec<_>>();
-    
+
     quote! {
         impl PrettyPrint for #type_ident {
             fn pretty_print(&self, writer: &mut IndentWriter) -> std::io::Result<()> {
@@ -159,6 +159,8 @@ fn make_leaf_struct_p2_impl(leaf_struct_build_spec: &LeafStructBuildSpec) -> Tok
         .members()
         .map(|member| match member.kind() {
             LeafStructMemberKind::String => Some("{}"),
+            LeafStructMemberKind::FileId => None,
+            LeafStructMemberKind::Range => None,
         })
         .filter(Option::is_some)
         .map(Option::unwrap)
@@ -169,12 +171,17 @@ fn make_leaf_struct_p2_impl(leaf_struct_build_spec: &LeafStructBuildSpec) -> Tok
 
     let members = leaf_struct_build_spec
         .members()
-        .map(|member| {
-            let member_ident = format_ident!("{}", member.name());
-            quote! {
-                self.#member_ident()
+        .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<_>>();
 
     quote! {
@@ -260,6 +267,6 @@ pub fn make_pretty_print_impl(build_spec: &BuildSpec) -> Option<TokenStream> {
         BuildSpec::PolymorphicPassThrough(_) => None,
         BuildSpec::PolymorphicEnumLoop(polymorphic_enum_loop) => {
             Some(make_polymorphic_enum_loop_p2_impl(polymorphic_enum_loop))
-        },
+        }
     }
 }
diff --git a/ast-generator/src/spec/leaf_struct_spec.rs b/ast-generator/src/spec/leaf_struct_spec.rs
index 0c12df4..eeb6952 100644
--- a/ast-generator/src/spec/leaf_struct_spec.rs
+++ b/ast-generator/src/spec/leaf_struct_spec.rs
@@ -44,4 +44,6 @@ impl LeafStructMember {
 
 pub enum LeafStructMemberKind {
     String,
+    FileId,
+    Range
 }
diff --git a/ast-generator/src/type_gen/leaf_struct_type.rs b/ast-generator/src/type_gen/leaf_struct_type.rs
index 0756fe3..1c7afb5 100644
--- a/ast-generator/src/type_gen/leaf_struct_type.rs
+++ b/ast-generator/src/type_gen/leaf_struct_type.rs
@@ -10,7 +10,9 @@ pub fn make_leaf_struct_type(build_spec: &LeafStructBuildSpec) -> TokenStream {
         .map(|member| {
             let name_ident = format_ident!("{}", member.name());
             let type_ident = match member.kind() {
-                LeafStructMemberKind::String => format_ident!("{}", "String"),
+                LeafStructMemberKind::String => quote! { String },
+                LeafStructMemberKind::FileId => quote! { usize },
+                LeafStructMemberKind::Range => quote! { Range<usize> },
             };
             quote! {
                 #name_ident: #type_ident
@@ -24,6 +26,12 @@ pub fn make_leaf_struct_type(build_spec: &LeafStructBuildSpec) -> TokenStream {
             LeafStructMemberKind::String => {
                 quote! { &str }
             }
+            LeafStructMemberKind::FileId => {
+                quote! { usize }
+            }
+            LeafStructMemberKind::Range => {
+                quote! { Range<usize> }
+            }
         };
         quote! {
             #name_ident: #type_stream
@@ -40,6 +48,7 @@ pub fn make_leaf_struct_type(build_spec: &LeafStructBuildSpec) -> TokenStream {
                         #member_ident: #member_ident.to_string()
                     }
                 }
+                _ => quote! { #member_ident },
             }
         })
         .collect::<Vec<_>>();
@@ -56,6 +65,20 @@ pub fn make_leaf_struct_type(build_spec: &LeafStructBuildSpec) -> TokenStream {
                         }
                     }
                 }
+                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<_>>();
diff --git a/src/ast/mod.rs b/src/ast/mod.rs
index 28e3991..18c6427 100644
--- a/src/ast/mod.rs
+++ b/src/ast/mod.rs
@@ -49,9 +49,9 @@ pub mod build {
 
     include!(concat!(env!("OUT_DIR"), "/src/ast/build.rs"));
 
-    pub fn build_ast(parsed_pairs: &mut Pairs<Rule>) -> Box<CompilationUnit> {
+    pub fn build_ast(file_id: usize, parsed_pairs: &mut Pairs<Rule>) -> Box<CompilationUnit> {
         let compilation_unit_pair = parsed_pairs.next().unwrap();
-        Box::new(build_compilation_unit(compilation_unit_pair))
+        Box::new(build_compilation_unit(file_id, compilation_unit_pair))
     }
 
     #[cfg(test)]
@@ -71,7 +71,7 @@ pub mod build {
                 Rule::BooleanLiteral,
                 include_str!("build_tests/boolean_literal/true"),
             );
-            assert_eq!(true, build_boolean_literal(pair));
+            assert_eq!(true, build_boolean_literal(0, pair));
         }
 
         #[test]
@@ -80,7 +80,7 @@ pub mod build {
                 Rule::BooleanLiteral,
                 include_str!("build_tests/boolean_literal/false"),
             );
-            assert_eq!(false, build_boolean_literal(pair));
+            assert_eq!(false, build_boolean_literal(0, pair));
         }
 
         #[test]
@@ -89,7 +89,7 @@ pub mod build {
                 Rule::BacktickInner,
                 include_str!("build_tests/backtick_inner/greeting"),
             );
-            assert_eq!("Hello, World!", build_backtick_inner(pair));
+            assert_eq!("Hello, World!", build_backtick_inner(0, pair));
         }
 
         #[test]
@@ -98,7 +98,7 @@ pub mod build {
                 Rule::BacktickString,
                 include_str!("build_tests/backtick_string/mixed"),
             );
-            let backtick_string = build_backtick_string(pair);
+            let backtick_string = build_backtick_string(0, pair);
             assert_eq!(backtick_string.inners().count(), 2);
             assert_eq!(backtick_string.expressions().count(), 1);
         }
@@ -106,20 +106,20 @@ pub mod build {
         #[test]
         fn d_string_expression_simple() {
             let pair = parse(Rule::DStringExpression, "${thing}");
-            let d_string_expression = build_d_string_expression(pair);
+            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(pair);
+            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(pair);
+            let d_string = build_d_string(0, pair);
             assert_eq!(d_string.inners().count(), 2);
             assert_eq!(d_string.expressions().count(), 1);
         }
@@ -127,7 +127,7 @@ pub mod build {
         #[test]
         fn expression_simple_call() {
             let pair = parse(Rule::Expression, "hello(42)");
-            let expression = build_expression(pair);
+            let expression = build_expression(0, pair);
         }
     }
 }
diff --git a/src/bin/dmc/p3.rs b/src/bin/dmc/p3.rs
index e7e99ac..d478f8f 100644
--- a/src/bin/dmc/p3.rs
+++ b/src/bin/dmc/p3.rs
@@ -10,7 +10,7 @@ pub fn pretty_print_parse(path: &PathBuf) {
     let parse_result = DeimosParser::parse(Rule::CompilationUnit, &src);
     match parse_result {
         Ok(mut pairs) => {
-            let compilation_unit = build_ast(&mut pairs);
+            let compilation_unit = build_ast(0, &mut pairs);
             let mut indent_writer = IndentWriter::new(0, "  ", Box::new(std::io::stdout()));
             compilation_unit
                 .pretty_print(&mut indent_writer)
diff --git a/src/parser/ast.schema.yaml b/src/parser/ast.schema.yaml
index c15de54..a2f816a 100644
--- a/src/parser/ast.schema.yaml
+++ b/src/parser/ast.schema.yaml
@@ -223,6 +223,8 @@ $defs:
       kind:
         enum:
           - string
+          - file_id
+          - range
     required:
       - kind
 
diff --git a/src/parser/ast.yaml b/src/parser/ast.yaml
index ae1b2e9..15c17fc 100644
--- a/src/parser/ast.yaml
+++ b/src/parser/ast.yaml
@@ -33,6 +33,10 @@ Identifier:
     members:
       - name:
           kind: string
+      - file_id:
+          kind: file_id
+      - range:
+          kind: range
 FullyQualifiedName:
   struct:
     children: