[project @ 2002-12-10 17:34:34 by simonpj]

Check for qualified names in binding positions in the parser instead
of the rename.  In External Core it's OK to have qualified names in
these places.

diff --git a/ghc/compiler/parser/RdrHsSyn.lhs b/ghc/compiler/parser/RdrHsSyn.lhs
index 4ef778a..6cf8adb 100644 (file)
--- a/ghc/compiler/parser/RdrHsSyn.lhs
+++ b/ghc/compiler/parser/RdrHsSyn.lhs
@@ -92,7 +92,7 @@ module RdrHsSyn (
 
 import HsSyn           -- Lots of it
 import RdrName         ( RdrName, isRdrTyVar, mkRdrUnqual, mkUnqual, rdrNameOcc, 
-                         isRdrTyVar, isRdrDataCon, isUnqual, getRdrName,
+                         isRdrTyVar, isRdrDataCon, isUnqual, getRdrName, isQual,
                          setRdrNameSpace )
 import BasicTypes      ( RecFlag(..), FixitySig(..), maxPrecedence )
 import Class            ( DefMeth (..) )
@@ -612,8 +612,9 @@ checkPat (HsApp f x) args =
        checkPat x [] `thenP` \x ->
        checkPat f (x:args)
 checkPat e [] = case e of
-       EWildPat           -> returnP (WildPat placeHolderType)
-       HsVar x            -> returnP (VarPat x)
+       EWildPat            -> returnP (WildPat placeHolderType)
+       HsVar x | isQual x  -> parseError ("Qualified variable in pattern: " ++ showRdrName x)
+               | otherwise -> returnP (VarPat x)
        HsLit l            -> returnP (LitPat l)
        HsOverLit l        -> returnP (NPatIn l Nothing)
        ELazyPat e         -> checkPat e [] `thenP` (returnP . LazyPat)
@@ -684,8 +685,11 @@ checkValDef
 
 checkValDef lhs opt_sig grhss loc
  = case isFunLhs lhs [] of
-          Just (f,inf,es) -> 
-               checkPatterns loc es `thenP` \ps ->
+          Just (f,inf,es) 
+            | isQual f
+            -> parseError ("Qualified name in function definition: "  ++ showRdrName f)
+            | otherwise
+            -> checkPatterns loc es `thenP` \ps ->
                returnP (RdrValBinding (FunMonoBind f inf [Match ps opt_sig grhss] loc))
 
            Nothing ->
@@ -862,6 +866,9 @@ mkIfaceExports decls = map getExport decls
 -- Misc utils
 
 \begin{code}
+showRdrName :: RdrName -> String
+showRdrName r = showSDoc (ppr r)
+
 parseError :: String -> P a
 parseError s = 
   getSrcLocP `thenP` \ loc ->

diff --git a/ghc/compiler/rename/RnEnv.lhs b/ghc/compiler/rename/RnEnv.lhs
index 4f2fc94..689d9a3 100644 (file)
--- a/ghc/compiler/rename/RnEnv.lhs
+++ b/ghc/compiler/rename/RnEnv.lhs
@@ -233,14 +233,11 @@ lookupTopBndrRn rdr_name
 -- A separate function (importsFromLocalDecls) reports duplicate top level
 -- decls, so here it's safe just to choose an arbitrary one.
 
-       -- There should never be a qualified name in a binding position 
-       -- The parser could check this, but doesn't (yet)
-  | isQual rdr_name
-  = getSrcLocM                                                 `thenM` \ loc ->
-    qualNameErr (text "In its declaration") (rdr_name,loc)     `thenM_`
-    returnM (mkUnboundName rdr_name)
+       -- There should never be a qualified name in a binding position in Haskell,
+       -- but there can be if we have read in an external-Core file.
+       -- The Haskell parser checks for the illegal qualified name, so we 
+       -- don't need to do so here.
 
-  | otherwise
   = ASSERT( not (isOrig rdr_name) )
        -- Original names are used only for occurrences, 
        -- not binding sites
@@ -338,15 +335,12 @@ lookupInstDeclBndr cls_name rdr_name
 
        other               -> pprPanic "lookupInstDeclBndr" (ppr cls_name)
 
-  | isQual rdr_name    -- Should never have a qualified name in a binding position
-  = getSrcLocM                                                 `thenM` \ loc ->
-    qualNameErr (text "In an instance method") (rdr_name,loc)  `thenM_`
-    returnM (mkUnboundName rdr_name)
-       
+
   | otherwise          -- Occurs in derived instances, where we just
                        -- refer directly to the right method, and avail_env
                        -- isn't available
   = ASSERT2( not (isQual rdr_name), ppr rdr_name )
+         -- NB: qualified names are rejected by the parser
     lookupOrigName rdr_name
 
   where
@@ -832,7 +826,9 @@ checkDupOrQualNames, checkDupNames :: SDoc
        -- Works in any variant of the renamer monad
 
 checkDupOrQualNames doc_str rdr_names_w_loc
-  =    -- Check for use of qualified names
+  =    -- Qualified names in patterns are now rejected by the parser
+       -- but I'm not 100% certain that it finds all cases, so I've left
+       -- this check in for now.  Should go eventually.
     mappM_ (qualNameErr doc_str) quals         `thenM_`
     checkDupNames doc_str rdr_names_w_loc
   where