From: simonpj <unknown>
Date: Mon, 27 Oct 2003 14:07:21 +0000 (+0000)
Subject: [project @ 2003-10-27 14:07:01 by simonpj]
X-Git-Tag: Approx_11550_changesets_converted~322
X-Git-Url: http://git.megacz.com/?a=commitdiff_plain;h=7222d3c0c93acdd47117b0f94cfb8858bd3c3789;hp=1f7a21ac55ad5769632c9d5e590e4e87f4d4f76a;p=ghc-hetmet.git

[project @ 2003-10-27 14:07:01 by simonpj]
Comments only
---

diff --git a/ghc/compiler/deSugar/Desugar.lhs b/ghc/compiler/deSugar/Desugar.lhs
index 67c6261..35083bd 100644
--- a/ghc/compiler/deSugar/Desugar.lhs
+++ b/ghc/compiler/deSugar/Desugar.lhs
@@ -84,13 +84,13 @@ deSugar hsc_env
         ; doIfSet (not (isEmptyBag warnings))
 		  (printErrs warn_doc)
 
-	    -- if warnings are considered errors, leave.
+	-- If warnings are considered errors, leave.
 	; if errorsFound dflags (warns, emptyBag)
 	   then return Nothing
-	   else do {
+	   else do
 
 	-- Lint result if necessary
-          endPass dflags "Desugar" Opt_D_dump_ds ds_binds
+	{ endPass dflags "Desugar" Opt_D_dump_ds ds_binds
 
 	-- Dump output
 	; doIfSet (dopt Opt_D_dump_ds dflags) 
diff --git a/ghc/compiler/typecheck/TcHsType.lhs b/ghc/compiler/typecheck/TcHsType.lhs
index 7e9338f..b1f9e97 100644
--- a/ghc/compiler/typecheck/TcHsType.lhs
+++ b/ghc/compiler/typecheck/TcHsType.lhs
@@ -303,9 +303,16 @@ kcHsType (HsForAllTy exp tv_names context ty)
   = kcHsTyVars tv_names		$ \ tv_names' ->
     kcHsContext context		`thenM`	\ ctxt' ->
     kcLiftedType ty		`thenM` \ ty' ->
-	-- The body of a forall must be of kind *
-	-- In principle, I suppose, we could allow unlifted types,
-	-- but it seems simpler to stick to lifted types for now.
+	-- The body of a forall must be a type, but in principle
+	-- there's no reason to prohibit *unlifted* types.
+	-- In fact, GHC can itself construct a function with an
+	-- unboxed tuple inside a for-all (via CPR analyis; see 
+	-- typecheck/should_compile/tc170)
+	--
+	-- Still, that's only for internal interfaces, which aren't
+	-- kind-checked, and it's a bit inconvenient to use kcTypeType
+	-- here (because it doesn't return the result kind), so I'm 
+	-- leaving it as lifted types for now.
     returnM (HsForAllTy exp tv_names' ctxt' ty', liftedTypeKind)
 
 ---------------------------