Add a conversion from our high-level IR to a lower-level one.

src/bin.rs

@@ -3,6 +3,7 @@ use codespan_reporting::diagnostic::Diagnostic;
 use codespan_reporting::files::SimpleFiles;
 use codespan_reporting::term;
 use codespan_reporting::term::termcolor::{ColorChoice, StandardStream};
+use ngr::asts::lil;
 use ngr::passes::run_front_end;
 use pretty::Arena;
 
@@ -27,15 +28,29 @@ fn main() {
     let config = codespan_reporting::term::Config::default();
 
     for error in hil_conversion_result.errors.drain(..) {
-        term::emit(&mut writer.lock(), &config, &file_database, &Diagnostic::from(error)).unwrap();
+        term::emit(
+            &mut writer.lock(),
+            &config,
+            &file_database,
+            &Diagnostic::from(error),
+        )
+        .unwrap();
     }
     for warning in hil_conversion_result.warnings.drain(..) {
-        term::emit(&mut writer.lock(), &config, &file_database, &Diagnostic::from(warning)).unwrap();
+        term::emit(
+            &mut writer.lock(),
+            &config,
+            &file_database,
+            &Diagnostic::from(warning),
+        )
+        .unwrap();
     }
 
-    if let Some((tree, variable_map)) = hil_conversion_result.result {
+    if let Some((hil_tree, mut variable_map)) = hil_conversion_result.result {
         let arena = Arena::new();
-        tree.pretty(&variable_map, &arena)
+        let lil_tree = lil::Program::convert(hil_tree, &mut variable_map);
+        lil_tree
+            .pretty(&variable_map, &arena)
             .into_doc()
             .render_colored(72, StandardStream::stdout(ColorChoice::Auto))
             .unwrap()