[project @ 2000-11-21 10:29:54 by simonpj]

Fix field name checking

diff --git a/ghc/compiler/rename/RnNames.lhs b/ghc/compiler/rename/RnNames.lhs
index 571ee3a..79cc35c 100644 (file)
--- a/ghc/compiler/rename/RnNames.lhs
+++ b/ghc/compiler/rename/RnNames.lhs
@@ -346,7 +346,8 @@ fully fledged @Names@.
 qualifyImports :: ModuleName           -- Imported module
               -> Bool                  -- True <=> want unqualified import
               -> Maybe ModuleName      -- Optional "as M" part 
-              -> [AvailInfo]           -- What's to be hidden
+              -> [AvailInfo]           -- What's to be hidden (but only the unqualified 
+                                       --      version is hidden)
               -> (Name -> Provenance)
               -> Avails                -- Whats imported and how
               -> RnMG (GlobalRdrEnv, ExportAvails)

diff --git a/ghc/compiler/typecheck/TcTyDecls.lhs b/ghc/compiler/typecheck/TcTyDecls.lhs
index 45afd7b..16e30e1 100644 (file)
--- a/ghc/compiler/typecheck/TcTyDecls.lhs
+++ b/ghc/compiler/typecheck/TcTyDecls.lhs
@@ -198,32 +198,34 @@ getBangStrictness (Unpacked _) = markedUnboxed
 
 \begin{code}
 tcRecordSelectors is_rec unf_env tycon data_cons
-  = mapTc tc_group groups
+       -- Omit the check that the fields have consistent types if 
+       -- the group is recursive; TcTyClsDecls.tcGroup will repeat 
+       -- with NonRecursive once we have tied the knot
+  | isRec is_rec = returnTc sel_ids
+  | otherwise   = mapTc check groups   `thenTc_` 
+                  returnTc sel_ids
   where
-    fields = [ (con, field) | con   <- data_cons,
-                             field <- dataConFieldLabels con ]
+    fields = [ field | con   <- data_cons
+                    , field <- dataConFieldLabels con ]
 
        -- groups is list of fields that share a common name
-    groups = equivClasses cmp_name fields
-    cmp_name (_, field1) (_, field2) 
-       = fieldLabelName field1 `compare` fieldLabelName field2
+    groups                = equivClasses cmp_name fields
+    cmp_name field1 field2 = fieldLabelName field1 `compare` fieldLabelName field2
 
-    tc_group fields@((first_con, first_field_label) : other_fields)
+    sel_ids = [ mkRecordSelId tycon field unpack_id unpackUtf8_id
+             | (field : _) <- groups ]
+
+    check fields@(first_field_label : other_fields)
        -- These fields all have the same name, but are from
        -- different constructors in the data type
        =       -- Check that all the fields in the group have the same type
-               -- Wimp out (omit check) if the group is recursive; 
-               -- TcTyClsDecls.tcGroup will repeat with NonRecursive once we
-               -- have tied the knot
                -- NB: this check assumes that all the constructors of a given
                -- data type use the same type variables
-         checkTc (not (isRec is_rec) && all (== field_ty) other_tys)
-                 (fieldTypeMisMatch field_name)        `thenTc_`
-         returnTc (mkRecordSelId tycon first_field_label unpack_id unpackUtf8_id)
+         checkTc (all (== field_ty) other_tys) (fieldTypeMisMatch field_name)
        where
            field_ty   = fieldLabelType first_field_label
            field_name = fieldLabelName first_field_label
-           other_tys  = [fieldLabelType fl | (_, fl) <- other_fields]
+           other_tys  = map fieldLabelType other_fields
 
     unpack_id     = tcLookupRecId unf_env unpackCStringName
     unpackUtf8_id = tcLookupRecId unf_env unpackCStringUtf8Name
@@ -240,7 +242,7 @@ tcRecordSelectors is_rec unf_env tycon data_cons
 
 \begin{code}
 fieldTypeMisMatch field_name
-  = sep [ptext SLIT("Declared types differ for field"), quotes (ppr field_name)]
+  = sep [ptext SLIT("Different constructors give different types for field"), quotes (ppr field_name)]
 
 exRecConErr name
   = ptext SLIT("Can't combine named fields with locally-quantified type variables")