[project @ 2003-02-21 13:27:53 by simonpj]

[ghc-hetmet.git] / ghc / compiler / typecheck / TcRnTypes.lhs

diff --git a/ghc/compiler/typecheck/TcRnTypes.lhs b/ghc/compiler/typecheck/TcRnTypes.lhs
index 1e58edd..b63ffc2 100644 (file)
--- a/ghc/compiler/typecheck/TcRnTypes.lhs
+++ b/ghc/compiler/typecheck/TcRnTypes.lhs
@@ -23,7 +23,7 @@ module TcRnTypes(
        ImportAvails(..), emptyImportAvails, plusImportAvails, 
        plusAvail, pruneAvails,  
        AvailEnv, emptyAvailEnv, unitAvailEnv, plusAvailEnv, 
-       mkAvailEnv, lookupAvailEnv, availEnvElts, addAvail,
+       mkAvailEnv, lookupAvailEnv, lookupAvailEnv_maybe, availEnvElts, addAvail,
        WhereFrom(..),
 
        -- Typechecker types
@@ -464,10 +464,11 @@ emptyUsages = emptyNameSet
 
 ImportAvails summarises what was imported from where, irrespective
 of whether the imported htings are actually used or not
-It is used     * when porcessing the export list
+It is used     * when processing the export list
                * when constructing usage info for the inteface file
                * to identify the list of directly imported modules
                        for initialisation purposes
+               * when figuring out what things are really unused
 
 \begin{code}
 data ImportAvails 
@@ -597,7 +598,13 @@ unitAvailEnv a = unitNameEnv (availName a) a
 plusAvailEnv :: AvailEnv -> AvailEnv -> AvailEnv
 plusAvailEnv = plusNameEnv_C plusAvail
 
-lookupAvailEnv = lookupNameEnv
+lookupAvailEnv_maybe :: AvailEnv -> Name -> Maybe AvailInfo
+lookupAvailEnv_maybe = lookupNameEnv
+
+lookupAvailEnv :: AvailEnv -> Name -> AvailInfo
+lookupAvailEnv env n = case lookupNameEnv env n of
+                        Just avail -> avail
+                        Nothing    -> pprPanic "lookupAvailEnv" (ppr n)
 
 availEnvElts = nameEnvElts