From b785be47556f5c1128e76355471fdb5de0a1ee64 Mon Sep 17 00:00:00 2001
From: simonpj <unknown>
Date: Wed, 18 Jan 2006 12:16:06 +0000
Subject: [PATCH] [project @ 2006-01-18 12:16:06 by simonpj] Check for
 constructors in type signatures

---
 ghc/compiler/basicTypes/OccName.lhs |    8 ++++++--
 ghc/compiler/parser/RdrHsSyn.lhs    |    6 ++++--
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/ghc/compiler/basicTypes/OccName.lhs b/ghc/compiler/basicTypes/OccName.lhs
index bd6d3f7..e553cc5 100644
--- a/ghc/compiler/basicTypes/OccName.lhs
+++ b/ghc/compiler/basicTypes/OccName.lhs
@@ -346,11 +346,15 @@ isValOcc other		      = False
 -- Data constructor operator (starts with ':', or '[]')
 -- Pretty inefficient!
 isDataSymOcc (OccName DataName s) = isLexConSym s
-isDataSymOcc (OccName VarName s)  = isLexConSym s
+isDataSymOcc (OccName VarName s)  
+  | isLexConSym s = pprPanic "isDataSymOcc: check me" (ppr s)
+		-- Jan06: I don't think this should happen
 isDataSymOcc other		  = False
 
 isDataOcc (OccName DataName _) = True
-isDataOcc (OccName VarName s)  = isLexCon s
+isDataOcc (OccName VarName s)  
+  | isLexCon s = pprPanic "isDataOcc: check me" (ppr s)
+		-- Jan06: I don't think this should happen
 isDataOcc other		       = False
 
 -- Any operator (data constructor or variable)
diff --git a/ghc/compiler/parser/RdrHsSyn.lhs b/ghc/compiler/parser/RdrHsSyn.lhs
index 6ff15e7..a955791 100644
--- a/ghc/compiler/parser/RdrHsSyn.lhs
+++ b/ghc/compiler/parser/RdrHsSyn.lhs
@@ -601,9 +601,11 @@ checkValSig
 	:: LHsExpr RdrName
 	-> LHsType RdrName
 	-> P (Sig RdrName)
-checkValSig (L l (HsVar v)) ty | isUnqual v = return (TypeSig (L l v) ty)
+checkValSig (L l (HsVar v)) ty 
+  | isUnqual v && not (isDataOcc (rdrNameOcc v))
+  = return (TypeSig (L l v) ty)
 checkValSig (L l other)     ty
-  = parseError l "Type signature given for an expression"
+  = parseError l "Invalid type signature"
 
 mkGadtDecl
         :: Located RdrName
-- 
1.7.10.4