Allowing wrapping math.

src/type_infer.rs

@@ -1,4 +1,15 @@
-/// A type inference pass for NGR
+//! A type inference pass for NGR
+//! 
+//! The type checker implemented here is a relatively straightforward one, designed to be
+//! fairly easy to understand rather than super fast. So don't be expecting the fastest
+//! type checker in the West, here.
+//! 
+//! The actual type checker operates in three phases. In the first phase, we translate
+//! the syntax AST into something that's close to the final IR. During the process, we
+//! generate a list of type constraints to solve. In the second phase, we try to solve
+//! all the constraints we've generated. If that's successful, in the final phase, we
+//! do the final conversion to the IR AST, filling in any type information we've learned
+//! along the way.
 mod ast;
 mod convert;
 mod finalize;