Inference on most expressions. HM based.

Still have to figure out how to infer type of lambda variables, as well
as how function application on polymorphic should work

src/TypeChecker/TypeCheckerIr.hs

@@ -0,0 +1,22 @@
+{-# LANGUAGE LambdaCase #-}
+
+module TypeChecker.TypeCheckerIr
+    ( Program(..)
+    , Bind(..)
+    , Ident
+    , Type(..)
+    , Const(..)
+    , Exp(..)
+    )
+        where
+
+import Grammar.Abs (Program(..), Bind(..), Ident, Type(..), Const(..))
+
+data Exp
+    = EAnn Exp Type
+    | EId Ident Type
+    | EConst Const Type
+    | EApp Exp Exp Type
+    | EAdd Exp Exp Type
+    | EAbs Ident Exp Type
+  deriving (Eq, Ord, Show, Read)