[project @ 2000-10-24 08:40:09 by simonpj]

[ghc-hetmet.git] / ghc / compiler / main / HscTypes.lhs

diff --git a/ghc/compiler/main/HscTypes.lhs b/ghc/compiler/main/HscTypes.lhs
index ee3c9e2..1b34ec0 100644 (file)
--- a/ghc/compiler/main/HscTypes.lhs
+++ b/ghc/compiler/main/HscTypes.lhs
@@ -9,7 +9,8 @@ module HscTypes (
 
        ModDetails(..), ModIface(..), GlobalSymbolTable, 
        HomeSymbolTable, PackageSymbolTable,
-       HomeIfaceTable, PackageIfaceTable,
+       HomeIfaceTable, PackageIfaceTable, 
+       lookupTable,
 
        IfaceDecls(..), 
 
@@ -19,8 +20,6 @@ module HscTypes (
 
        TypeEnv, extendTypeEnv, lookupTypeEnv, 
 
-       lookupFixityEnv,
-
        WhetherHasOrphans, ImportVersion, WhatsImported(..),
        PersistentRenamerState(..), IsBootInterface, Avails, DeclsMap,
        IfaceInsts, IfaceRules, GatedDecl,
@@ -68,6 +67,7 @@ import Type           ( Type )
 
 import FiniteMap       ( FiniteMap, emptyFM, addToFM, lookupFM, foldFM )
 import Bag             ( Bag )
+import Maybes          ( seqMaybe )
 import UniqFM          ( UniqFM )
 import Outputable
 import SrcLoc          ( SrcLoc, isGoodSrcLoc )
@@ -118,7 +118,10 @@ data ModIface
         mi_version  :: VersionInfo,            -- Module version number
         mi_orphan   :: WhetherHasOrphans,       -- Whether this module has orphans
 
-        mi_usages   :: [ImportVersion Name],   -- Usages; kept sorted
+        mi_usages   :: [ImportVersion Name],   -- Usages; kept sorted so that it's easy
+                                               -- to decide whether to write a new iface file
+                                               -- (changing usages doesn't affect the version of
+                                               --  this module)
 
         mi_exports  :: Avails,                 -- What it exports
                                                -- Kept sorted by (mod,occ),
@@ -182,11 +185,12 @@ type GlobalSymbolTable  = SymbolTable     -- Domain = all modules
 Simple lookups in the symbol table.
 
 \begin{code}
-lookupFixityEnv :: IfaceTable -> Name -> Maybe Fixity
-lookupFixityEnv tbl name
-  = case lookupModuleEnv tbl (nameModule name) of
-       Nothing      -> Nothing
-       Just details -> lookupNameEnv (mi_fixities details) name
+lookupTable :: ModuleEnv a -> ModuleEnv a -> Name -> Maybe a
+-- We often have two Symbol- or IfaceTables, and want to do a lookup
+lookupTable ht pt name
+  = lookupModuleEnv ht mod `seqMaybe` lookupModuleEnv pt mod
+  where
+    mod = nameModule name
 \end{code}