Experimenting with build.rs, quote, and syn.

Cargo.lock

@@ -51,6 +51,15 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "ast-generator"
+version = "0.1.0"
+dependencies = [
+ "prettyplease",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "block-buffer"
 version = "0.10.4"
@@ -146,6 +155,7 @@ dependencies = [
 name = "deimos"
 version = "0.1.0"
 dependencies = [
+ "ast-generator",
  "clap",
  "codespan-reporting",
  "indoc",
@@ -261,6 +271,16 @@ dependencies = [
  "sha2",
 ]
 
+[[package]]
+name = "prettyplease"
+version = "0.2.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "479ca8adacdd7ce8f1fb39ce9ecccbfe93a3f1344b3d0d97f20bc0196208f62b"
+dependencies = [
+ "proc-macro2",
+ "syn",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.92"
@@ -272,9 +292,9 @@ dependencies = [
 
 [[package]]
 name = "quote"
-version = "1.0.37"
+version = "1.0.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
+checksum = "1885c039570dc00dcb4ff087a89e185fd56bae234ddc7f056a945bf36467248d"
 dependencies = [
  "proc-macro2",
 ]
@@ -318,9 +338,9 @@ checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
 [[package]]
 name = "syn"
-version = "2.0.90"
+version = "2.0.106"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "919d3b74a5dd0ccd15aeb8f93e7006bd9e14c295087c9896a110f490752bcf31"
+checksum = "ede7c438028d4436d71104916910f5bb611972c5cfd7f89b8300a8186e6fada6"
 dependencies = [
  "proc-macro2",
  "quote",

Cargo.toml

@@ -18,3 +18,10 @@ pest_derive = { version = "2.8.0", features = ["grammar-extras"] }
 codespan-reporting = "0.12.0"
 log = "0.4.27"
 indoc = "2.0.6"
+
+[build-dependencies]
+ast-generator = { path = "ast-generator" }
+
+[workspace]
+resolver = "3"
+members = ["ast-generator"]

ast-generator/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "ast-generator"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+prettyplease = "0.2.37"
+quote = "1.0.40"
+syn = "2.0.106"

ast-generator/src/lib.rs

@@ -0,0 +1,30 @@
+use quote::quote;
+
+pub fn add(left: u64, right: u64) -> u64 {
+    left + right
+}
+
+pub fn speak(s: &str) {
+    println!("{}", s);
+}
+
+pub fn do_some_quoting(msg: &str) -> String {
+    let output = quote! {
+        pub fn some_quoting() {
+            println!(#msg);
+        }
+    };
+    let syntax_tree = syn::parse2(output).unwrap();
+    prettyplease::unparse(&syntax_tree)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_works() {
+        let result = add(2, 2);
+        assert_eq!(result, 4);
+    }
+}

build.rs

@@ -0,0 +1,14 @@
+use std::env;
+use std::fs::write;
+use std::path::Path;
+use ast_generator::do_some_quoting;
+
+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 = do_some_quoting("Hello, World!");
+    write(&testing_txt_path, output)?;
+    Ok(())
+}