[checkpoint] Start the switch to type inference.

src/compiler.rs

@@ -1,5 +1,4 @@
 use crate::backend::Backend;
-use crate::ir::Program as IR;
 use crate::syntax::Program as Syntax;
 use codespan_reporting::{
     diagnostic::Diagnostic,
@@ -101,7 +100,7 @@ impl Compiler {
         }
 
         // Now that we've validated it, turn it into IR.
-        let ir = IR::from(syntax);
+        let ir = syntax.type_infer();
 
         // Finally, send all this to Cranelift for conversion into an object file.
         let mut backend = Backend::object_file(Triple::host())?;