move AvailInfo and related things into its own module

19 files changed, 149 insertions, 108 deletions

diff --git a/compiler/basicTypes/Avail.hs b/compiler/basicTypes/Avail.hs
new file mode 100644
index 0000000000..8bf622e13d
--- /dev/null
+++ b/compiler/basicTypes/Avail.hs
@@ -0,0 +1,107 @@
+--
+-- (c) The University of Glasgow
+--
+
+module Avail (
+    Avails,
+    AvailInfo(..),
+    availsToNameSet,
+    availsToNameEnv,
+    availName, availNames,
+    stableAvailCmp,
+    gresFromAvails,
+    gresFromAvail
+  ) where
+
+import Name
+import NameEnv
+import NameSet
+import RdrName
+
+import Outputable
+import Util
+
+-- -----------------------------------------------------------------------------
+-- The AvailInfo type
+
+-- | Records what things are "available", i.e. in scope
+data AvailInfo = Avail Name	 -- ^ An ordinary identifier in scope
+	       | AvailTC Name
+			 [Name]  -- ^ A type or class in scope. Parameters:
+			         --
+				 --  1) The name of the type or class
+				 --  2) The available pieces of type or class.
+				 -- 
+				 -- The AvailTC Invariant:
+                                 --   * If the type or class is itself
+				 --     to be in scope, it must be
+				 --     *first* in this list.  Thus,
+                                 --     typically: @AvailTC Eq [Eq, ==, \/=]@
+		deriving( Eq )
+                        -- Equality used when deciding if the
+                        -- interface has changed
+
+-- | A collection of 'AvailInfo' - several things that are \"available\"
+type Avails	  = [AvailInfo]
+
+-- | Compare lexicographically
+stableAvailCmp :: AvailInfo -> AvailInfo -> Ordering
+stableAvailCmp (Avail n1)     (Avail n2)     = n1 `stableNameCmp` n2
+stableAvailCmp (Avail {})     (AvailTC {})   = LT
+stableAvailCmp (AvailTC n ns) (AvailTC m ms) = (n `stableNameCmp` m) `thenCmp`
+                                               (cmpList stableNameCmp ns ms)
+stableAvailCmp (AvailTC {})   (Avail {})     = GT
+
+
+-- -----------------------------------------------------------------------------
+-- Operations on AvailInfo
+
+availsToNameSet :: [AvailInfo] -> NameSet
+availsToNameSet avails = foldr add emptyNameSet avails
+      where add avail set = addListToNameSet set (availNames avail)
+
+availsToNameEnv :: [AvailInfo] -> NameEnv AvailInfo
+availsToNameEnv avails = foldr add emptyNameEnv avails
+     where add avail env = extendNameEnvList env
+                                (zip (availNames avail) (repeat avail))
+
+-- | Just the main name made available, i.e. not the available pieces
+-- of type or class brought into scope by the 'GenAvailInfo'
+availName :: AvailInfo -> Name
+availName (Avail n)     = n
+availName (AvailTC n _) = n
+
+-- | All names made available by the availability information
+availNames :: AvailInfo -> [Name]
+availNames (Avail n)      = [n]
+availNames (AvailTC _ ns) = ns
+
+-- | make a 'GlobalRdrEnv' where all the elements point to the same
+-- Provenance (useful for "hiding" imports, or imports with
+-- no details).
+gresFromAvails :: Provenance -> [AvailInfo] -> [GlobalRdrElt]
+gresFromAvails prov avails
+  = concatMap (gresFromAvail (const prov)) avails
+
+gresFromAvail :: (Name -> Provenance) -> AvailInfo -> [GlobalRdrElt]
+gresFromAvail prov_fn avail
+  = [ GRE {gre_name = n,
+           gre_par = parent n avail,
+           gre_prov = prov_fn n}
+    | n <- availNames avail ]
+  where
+    parent _ (Avail _)                 = NoParent
+    parent n (AvailTC m _) | n == m    = NoParent
+                           | otherwise = ParentIs m
+
+-- -----------------------------------------------------------------------------
+-- Printing
+
+instance Outputable AvailInfo where
+   ppr = pprAvail
+
+pprAvail :: AvailInfo -> SDoc
+pprAvail (Avail n)      = ppr n
+pprAvail (AvailTC n ns) = ppr n <> braces (hsep (punctuate comma (map ppr ns)))
+
+
diff --git a/compiler/deSugar/Desugar.lhs b/compiler/deSugar/Desugar.lhs
index 9001ec7cf5..d85ff0a8df 100644
--- a/compiler/deSugar/Desugar.lhs
+++ b/compiler/deSugar/Desugar.lhs
@@ -16,6 +16,7 @@ import TcRnTypes
 import MkIface
 import Id
 import Name
+import Avail
 import CoreSyn
 import CoreSubst
 import PprCore
diff --git a/compiler/ghc.cabal.in b/compiler/ghc.cabal.in
index eea42bf981..01bbeb067d 100644
--- a/compiler/ghc.cabal.in
+++ b/compiler/ghc.cabal.in
@@ -146,6 +146,7 @@ Library
         vectorise
 
     Exposed-Modules:
+        Avail
         BasicTypes
         DataCon
         Demand
diff --git a/compiler/iface/BinIface.hs b/compiler/iface/BinIface.hs
index 55ab378ea1..083e85c27b 100644
--- a/compiler/iface/BinIface.hs
+++ b/compiler/iface/BinIface.hs
@@ -21,6 +21,7 @@ import Annotations
 import IfaceSyn
 import Module
 import Name
+import Avail
 import VarEnv
 import DynFlags
 import UniqFM
diff --git a/compiler/iface/IfaceEnv.lhs b/compiler/iface/IfaceEnv.lhs
index 798164c448..98c21fd286 100644
--- a/compiler/iface/IfaceEnv.lhs
+++ b/compiler/iface/IfaceEnv.lhs
@@ -27,6 +27,7 @@ import Type
 import DataCon
 import Var
 import Name
+import Avail
 import PrelNames
 import Module
 import UniqFM
diff --git a/compiler/iface/LoadIface.lhs b/compiler/iface/LoadIface.lhs
index b9e72a6c1f..bbee0424ff 100644
--- a/compiler/iface/LoadIface.lhs
+++ b/compiler/iface/LoadIface.lhs
@@ -43,6 +43,7 @@ import InstEnv
 import FamInstEnv
 import Name
 import NameEnv
+import Avail
 import Module
 import Maybes
 import ErrUtils
diff --git a/compiler/iface/MkIface.lhs b/compiler/iface/MkIface.lhs
index c56e9854e0..1688d2314d 100644
--- a/compiler/iface/MkIface.lhs
+++ b/compiler/iface/MkIface.lhs
@@ -75,6 +75,7 @@ import VarEnv
 import VarSet
 import Var
 import Name
+import Avail
 import RdrName
 import NameEnv
 import NameSet
diff --git a/compiler/main/GHC.hs b/compiler/main/GHC.hs
index d803ea85fb..928f21e8ff 100644
--- a/compiler/main/GHC.hs
+++ b/compiler/main/GHC.hs
@@ -265,6 +265,7 @@ import TyCon
 import Class
 import DataCon
 import Name             hiding ( varName )
+import Avail
 import InstEnv
 import FamInstEnv
 import SrcLoc
@@ -276,8 +277,7 @@ import HscTypes
 import DynFlags
 import StaticFlagParser
 import qualified StaticFlags
-import SysTools     ( initSysTools, cleanTempFiles, 
-                      cleanTempDirs )
+import SysTools
 import Annotations
 import Module
 import UniqFM
diff --git a/compiler/main/HscTypes.lhs b/compiler/main/HscTypes.lhs
index 0b90fd9668..79c5c13c42 100644
--- a/compiler/main/HscTypes.lhs
+++ b/compiler/main/HscTypes.lhs
@@ -74,9 +74,7 @@ module HscTypes (
 	WhetherHasOrphans, IsBootInterface, Usage(..), 
 	Dependencies(..), noDependencies,
 	NameCache(..), OrigNameCache, OrigIParamCache,
-	Avails, availsToNameSet, availsToNameEnv, availName, availNames,
-        AvailInfo(..), gresFromAvails, gresFromAvail,
-        IfaceExport, stableAvailCmp,
+        IfaceExport,
 
 	-- * Warnings
 	Warnings(..), WarningTxt(..), plusWarns,
@@ -116,6 +114,7 @@ import {-# SOURCE #-}  InteractiveEval ( Resume )
 import HsSyn
 import RdrName
 import Name
+import Avail
 import NameEnv
 import NameSet  
 import Module
@@ -695,6 +694,9 @@ data ModIface
                 -- See Note [RnNames . Trust Own Package]
      }
 
+-- | The original names declared of a certain module that are exported
+type IfaceExport = AvailInfo
+
 -- | The 'ModDetails' is essentially a cache for information in the 'ModIface'
 -- for home modules only. Information relating to packages will be loaded into
 -- global environments in 'ExternalPackageState'.
@@ -1473,82 +1475,6 @@ plusWarns _ (WarnAll t) = WarnAll t
 plusWarns (WarnAll t) _ = WarnAll t
 plusWarns (WarnSome v1) (WarnSome v2) = WarnSome (v1 ++ v2)
 \end{code}
-\begin{code}
--- | A collection of 'AvailInfo' - several things that are \"available\"
-type Avails	  = [AvailInfo]
-
--- | Records what things are "available", i.e. in scope
-data AvailInfo = Avail Name	 -- ^ An ordinary identifier in scope
-	       | AvailTC Name
-			 [Name]  -- ^ A type or class in scope. Parameters:
-			         --
-				 --  1) The name of the type or class
-				 --  2) The available pieces of type or class.
-				 -- 
-				 -- The AvailTC Invariant:
-				 --   * If the type or class is itself
-				 --     to be in scope, it must be *first* in this list.
-				 --     Thus, typically: @AvailTC Eq [Eq, ==, \/=]@
-		deriving( Eq )
-			-- Equality used when deciding if the interface has changed
-
--- | The original names declared of a certain module that are exported
-type IfaceExport = AvailInfo
-
-availsToNameSet :: [AvailInfo] -> NameSet
-availsToNameSet avails = foldr add emptyNameSet avails
-      where add avail set = addListToNameSet set (availNames avail)
-
-availsToNameEnv :: [AvailInfo] -> NameEnv AvailInfo
-availsToNameEnv avails = foldr add emptyNameEnv avails
-     where add avail env = extendNameEnvList env
-                                (zip (availNames avail) (repeat avail))
-
--- | Just the main name made available, i.e. not the available pieces
--- of type or class brought into scope by the 'GenAvailInfo'
-availName :: AvailInfo -> Name
-availName (Avail n)     = n
-availName (AvailTC n _) = n
-
--- | All names made available by the availability information
-availNames :: AvailInfo -> [Name]
-availNames (Avail n)      = [n]
-availNames (AvailTC _ ns) = ns
-
--- | make a 'GlobalRdrEnv' where all the elements point to the same
--- import declaration (useful for "hiding" imports, or imports with
--- no details).
-gresFromAvails :: Provenance -> [AvailInfo] -> [GlobalRdrElt]
-gresFromAvails prov avails
-  = concatMap (gresFromAvail (const prov)) avails
-
-gresFromAvail :: (Name -> Provenance) -> AvailInfo -> [GlobalRdrElt]
-gresFromAvail prov_fn avail
-  = [ GRE {gre_name = n,
-           gre_par = parent n avail,
-           gre_prov = prov_fn n}
-    | n <- availNames avail ]
-  where
-    parent _ (Avail _)                 = NoParent
-    parent n (AvailTC m _) | n == m    = NoParent
-                           | otherwise = ParentIs m
-
-
-instance Outputable AvailInfo where
-   ppr = pprAvail
-
-pprAvail :: AvailInfo -> SDoc
-pprAvail (Avail n)      = ppr n
-pprAvail (AvailTC n ns) = ppr n <> braces (hsep (punctuate comma (map ppr ns)))
-
-stableAvailCmp :: AvailInfo -> AvailInfo -> Ordering
--- Compare lexicographically
-stableAvailCmp (Avail n1)     (Avail n2)     = n1 `stableNameCmp` n2
-stableAvailCmp (Avail {})     (AvailTC {})   = LT
-stableAvailCmp (AvailTC n ns) (AvailTC m ms) = (n `stableNameCmp` m) `thenCmp`
-                                               (cmpList stableNameCmp ns ms)
-stableAvailCmp (AvailTC {})   (Avail {})     = GT
-\end{code}
 
 \begin{code}
 -- | Creates cached lookup for the 'mi_fix_fn' field of 'ModIface'
diff --git a/compiler/main/InteractiveEval.hs b/compiler/main/InteractiveEval.hs
index 3e763d55eb..47beb275e3 100644
--- a/compiler/main/InteractiveEval.hs
+++ b/compiler/main/InteractiveEval.hs
@@ -49,6 +49,7 @@ import Var
 import Id
 import Name             hiding ( varName )
 import NameSet
+import Avail
 import RdrName
 import PrelNames (pRELUDE)
 import VarSet
diff --git a/compiler/main/TidyPgm.lhs b/compiler/main/TidyPgm.lhs
index 050931c813..2d90c2c334 100644
--- a/compiler/main/TidyPgm.lhs
+++ b/compiler/main/TidyPgm.lhs
@@ -31,8 +31,9 @@ import Demand
 import BasicTypes
 import Name hiding (varName)
 import NameSet
-import IfaceEnv
 import NameEnv
+import Avail
+import IfaceEnv
 import TcType
 import DataCon
 import TyCon
diff --git a/compiler/prelude/PrelInfo.lhs b/compiler/prelude/PrelInfo.lhs
index f99f9ca292..5c02313965 100644
--- a/compiler/prelude/PrelInfo.lhs
+++ b/compiler/prelude/PrelInfo.lhs
@@ -22,21 +22,20 @@ module PrelInfo (
 
 #include "HsVersions.h"
 
-import PrelNames        ( basicKnownKeyNames,
-                          hasKey, charDataConKey, intDataConKey,
-                          numericClassKeys, standardClassKeys )
+import PrelNames
 import PrelRules
-import PrimOp		( PrimOp, allThePrimOps, primOpTag, maxPrimOpTag )
-import DataCon		( DataCon )
-import Id		( Id, idName )
-import MkId		-- All of it, for re-export
-import TysPrim		( primTyCons )
-import TysWiredIn	( wiredInTyCons )
-import HscTypes 	( TyThing(..), implicitTyThings, AvailInfo(..), IfaceExport )
-import Class	 	( Class, classKey )
-import Type		( funTyCon )
-import TyCon		( tyConName )
-import Util		( isIn )
+import Avail
+import PrimOp
+import DataCon
+import Id
+import MkId
+import TysPrim
+import TysWiredIn
+import HscTypes
+import Class
+import Type
+import TyCon
+import Util
 
 import Data.Array
 \end{code}
diff --git a/compiler/rename/RnBinds.lhs b/compiler/rename/RnBinds.lhs
index 5fd0f1cc0c..ad46cb038b 100644
--- a/compiler/rename/RnBinds.lhs
+++ b/compiler/rename/RnBinds.lhs
@@ -29,16 +29,13 @@ import HsSyn
 import RnHsSyn
 import TcRnMonad
 import RnTypes        ( rnIPName, rnHsSigType, rnLHsType, checkPrecMatch )
-import RnPat          (rnPats, rnBindPat,
-                       NameMaker, localRecNameMaker, topRecNameMaker, applyNameMaker
-                      )
-                      
+import RnPat
 import RnEnv
 import DynFlags
 import Name
 import NameEnv
 import NameSet
-import RdrName		( RdrName, rdrNameOcc )
+import RdrName          ( RdrName, rdrNameOcc )
 import SrcLoc
 import ListSetOps	( findDupsEq )
 import BasicTypes	( RecFlag(..) )
diff --git a/compiler/rename/RnEnv.lhs b/compiler/rename/RnEnv.lhs
index cfdeab29c9..9771ab16a8 100644
--- a/compiler/rename/RnEnv.lhs
+++ b/compiler/rename/RnEnv.lhs
@@ -36,17 +36,18 @@ module RnEnv (
 #include "HsVersions.h"
 
 import LoadIface	( loadInterfaceForName, loadSrcInterface )
-import IfaceEnv		( lookupOrig, newGlobalBinder, updNameCache, extendNameCache )
+import IfaceEnv
 import HsSyn
 import RdrHsSyn		( extractHsTyRdrTyVars )
 import RdrName
-import HscTypes		( NameCache(..), availNames, ModIface(..), FixItem(..), lookupFixity)
+import HscTypes
 import TcEnv		( tcLookupDataCon, tcLookupField, isBrackStage )
 import TcRnMonad
 import Id		( isRecordSelector )
 import Name
 import NameSet
 import NameEnv
+import Avail
 import Module           ( ModuleName, moduleName )
 import UniqFM
 import DataCon		( dataConFieldLabels )
diff --git a/compiler/rename/RnNames.lhs b/compiler/rename/RnNames.lhs
index 574550f1ff..ce14ad258f 100644
--- a/compiler/rename/RnNames.lhs
+++ b/compiler/rename/RnNames.lhs
@@ -25,6 +25,7 @@ import Module
 import Name
 import NameEnv
 import NameSet
+import Avail
 import HscTypes
 import RdrName
 import Outputable
diff --git a/compiler/rename/RnSource.lhs b/compiler/rename/RnSource.lhs
index 0a3d3ffc25..1d7e956dae 100644
--- a/compiler/rename/RnSource.lhs
+++ b/compiler/rename/RnSource.lhs
@@ -20,11 +20,9 @@ import RdrName
 import RdrHsSyn		( extractHsRhoRdrTyVars )
 import RnHsSyn
 import RnTypes
-import RnBinds		( rnTopBindsLHS, rnTopBindsRHS, rnMethodBinds, 
-                          renameSigs, mkSigTvFn, makeMiniFixityEnv )
+import RnBinds
 import RnEnv
-import RnNames       	( getLocalNonValBinders, extendGlobalRdrEnvRn, lookupTcdName )
-import HscTypes      	( AvailInfo(..) )
+import RnNames
 import RnHsDoc          ( rnHsDoc, rnMbLHsDoc )
 import TcRnMonad
 import Kind             ( liftedTypeKind )
@@ -33,9 +31,10 @@ import ForeignCall	( CCallTarget(..) )
 import Module
 import HscTypes		( Warnings(..), plusWarns )
 import Class		( FunDep )
-import Name		( Name, nameOccName )
+import Name
 import NameSet
 import NameEnv
+import Avail
 import Outputable
 import Bag
 import FastString
diff --git a/compiler/typecheck/TcRnDriver.lhs b/compiler/typecheck/TcRnDriver.lhs
index 21b71b2c6a..ed05220d64 100644
--- a/compiler/typecheck/TcRnDriver.lhs
+++ b/compiler/typecheck/TcRnDriver.lhs
@@ -66,6 +66,7 @@ import UniqFM
 import Name
 import NameEnv
 import NameSet
+import Avail
 import TyCon
 import SrcLoc
 import HscTypes
diff --git a/compiler/typecheck/TcRnTypes.lhs b/compiler/typecheck/TcRnTypes.lhs
index 58c3aa6a43..937cbac53b 100644
--- a/compiler/typecheck/TcRnTypes.lhs
+++ b/compiler/typecheck/TcRnTypes.lhs
@@ -76,6 +76,7 @@ import RdrName
 import Name
 import NameEnv
 import NameSet
+import Avail
 import Var
 import VarEnv
 import Module
diff --git a/compiler/typecheck/TcTyDecls.lhs b/compiler/typecheck/TcTyDecls.lhs
index 02ac0b824b..4314fb5d9f 100644
--- a/compiler/typecheck/TcTyDecls.lhs
+++ b/compiler/typecheck/TcTyDecls.lhs
@@ -26,6 +26,7 @@ import DataCon
 import Name
 import NameEnv
 import NameSet
+import Avail
 import Digraph
 import BasicTypes
 import SrcLoc