From: Matthijs Kooijman <m.kooijman@student.utwente.nl>
Date: Sun, 21 Jun 2009 15:24:29 +0000 (+0200)
Subject: Don't propagate types with free tyvars.
X-Git-Url: https://git.stderr.nl/gitweb?a=commitdiff_plain;h=f18e8ab055de511846f09efc7752628013142d0f;p=matthijs%2Fmaster-project%2Fc%CE%BBash.git

Don't propagate types with free tyvars.

Any free type variables in a type argument wouldn't be in scope in the new
function. Eventually, beta reducation and applicable inlining should make
sure that all type variables are resolved.
---

diff --git a/Normalize.hs b/Normalize.hs
index d06670c..0d58d04 100644
--- a/Normalize.hs
+++ b/Normalize.hs
@@ -294,8 +294,10 @@ appsimpltop = everywhere ("appsimpl", appsimpl)
 typeprop, typeproptop :: Transform
 -- Transform any function that is applied to a type argument. Since type
 -- arguments are always the first ones to apply and we'll remove all type
--- arguments, we can simply do them one by one.
-typeprop expr@(App (Var f) (Type ty)) = do
+-- arguments, we can simply do them one by one. We only propagate type
+-- arguments without any free tyvars, since tyvars those wouldn't be in scope
+-- in the new function.
+typeprop expr@(App (Var f) arg@(Type ty)) | not $ has_free_tyvars arg = do
   id <- cloneVar f
   let newty = Type.applyTy (Id.idType f) ty
   let newf = Var.setVarType id newty