[project @ 2001-02-20 09:45:30 by simonpj]

A bit more on deprecations

diff --git a/ghc/compiler/rename/RnNames.lhs b/ghc/compiler/rename/RnNames.lhs
index 750ffb0..d56b708 100644 (file)
--- a/ghc/compiler/rename/RnNames.lhs
+++ b/ghc/compiler/rename/RnNames.lhs
@@ -19,8 +19,8 @@ import HsSyn          ( HsModule(..), HsDecl(..), IE(..), ieName, ImportDecl(..),
 import RdrHsSyn                ( RdrNameIE, RdrNameImportDecl,
                          RdrNameHsModule, RdrNameHsDecl
                        )
-import RnIfaces                ( getInterfaceExports, recordLocalSlurps )
-import RnHiFiles       ( getTyClDeclBinders )
+import RnIfaces                ( recordLocalSlurps )
+import RnHiFiles       ( getTyClDeclBinders, loadInterface )
 import RnEnv
 import RnMonad
 
@@ -32,7 +32,9 @@ import Module         ( ModuleName, moduleName, WhereFrom(..) )
 import NameSet
 import Name            ( Name, nameSrcLoc, nameOccName,  nameEnvElts )
 import HscTypes                ( Provenance(..), ImportReason(..), GlobalRdrEnv,
-                         GenAvailInfo(..), AvailInfo, Avails, AvailEnv )
+                         GenAvailInfo(..), AvailInfo, Avails, AvailEnv, 
+                         Deprecations(..), ModIface(..)
+                       )
 import RdrName         ( RdrName, rdrNameOcc, setRdrNameOcc )
 import OccName         ( setOccNameSpace, dataName )
 import NameSet         ( elemNameSet, emptyNameSet )
@@ -124,15 +126,14 @@ importsFromImportDecl :: ModuleName
 
 importsFromImportDecl this_mod_name (ImportDecl imp_mod_name from qual_only as_mod import_spec iloc)
   = pushSrcLocRn iloc $
-    getInterfaceExports imp_mod_name from      `thenRn` \ (imp_mod, avails_by_module) ->
-
-    if null avails_by_module then
-       -- If there's an error in getInterfaceExports, (e.g. interface
-       -- file not found) we get lots of spurious errors from 'filterImports'
-       returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name)
-    else
 
+    loadInterface (ppr imp_mod_name <+> ptext SLIT("is directly imported"))
+                 imp_mod_name from                     `thenRn` \ iface ->
     let
+       imp_mod          = mi_module iface
+       avails_by_module = mi_exports iface
+       deprecs          = mi_deprecs iface
+
        avails :: Avails
        avails = [ avail | (mod_name, avails) <- avails_by_module,
                           mod_name /= this_mod_name,
@@ -155,6 +156,19 @@ importsFromImportDecl this_mod_name (ImportDecl imp_mod_name from qual_only as_m
        -- then you'll get a 'B does not export AType' message.  Oh well.
 
     in
+    if null avails_by_module then
+       -- If there's an error in loadInterface, (e.g. interface
+       -- file not found) we get lots of spurious errors from 'filterImports'
+       returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name)
+    else
+
+       -- Complain if we import a deprecated module
+    (case deprecs of   
+       DeprecAll txt -> addWarnRn (moduleDeprec imp_mod_name txt)
+       other         -> returnRn ()
+    )                                                  `thenRn_`
+
+       -- Filter the imports according to the import list
     filterImports imp_mod_name from import_spec avails `thenRn` \ (filtered_avails, hides, explicits) ->
 
     let
@@ -164,7 +178,7 @@ importsFromImportDecl this_mod_name (ImportDecl imp_mod_name from qual_only as_m
                        Just another_name -> another_name
 
        mk_prov name = NonLocalDef (UserImport imp_mod iloc (name `elemNameSet` explicits)) 
-       gbl_env      = mkGlobalRdrEnv qual_mod unqual_imp True hides mk_prov filtered_avails
+       gbl_env      = mkGlobalRdrEnv qual_mod unqual_imp True hides mk_prov filtered_avails deprecs
        exports      = mkExportAvails qual_mod unqual_imp gbl_env            filtered_avails
     in
     returnRn (gbl_env, exports)
@@ -195,7 +209,15 @@ importsFromLocalDecls this_mod decls
        unqual_imp = True       -- Want unqualified names
        mk_prov n  = LocalDef   -- Provenance is local
        hides      = []         -- Hide nothing
-       gbl_env    = mkGlobalRdrEnv mod_name unqual_imp True hides mk_prov avails
+
+       gbl_env    = mkGlobalRdrEnv mod_name unqual_imp True hides mk_prov avails NoDeprecs
+           -- NoDeprecs: don't complain about locally defined names
+           -- For a start, we may be exporting a deprecated thing
+           -- Also we may use a deprecated thing in the defn of another
+           -- deprecated things.  We may even use a deprecated thing in
+           -- the defn of a non-deprecated thing, when changing a module's 
+           -- interface
+
        exports    = mkExportAvails mod_name unqual_imp gbl_env            avails
     in
     returnRn (gbl_env, exports)
@@ -568,4 +590,8 @@ dupModuleExport mod
   = hsep [ptext SLIT("Duplicate"),
          quotes (ptext SLIT("Module") <+> ppr mod), 
           ptext SLIT("in export list")]
+
+moduleDeprec mod txt
+  = sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"), 
+         nest 4 (ppr txt) ]      
 \end{code}