Preparation for rendering instances as separate declarations

We want to be able to render instances as separate declarations. So we remove
the Name argument of ExportDecl, since instances are nameless.

This patch also contains the first steps needed to gather type family instances 
and display them in the backend, but the implementation is far from complete.
Because of this, we don't actually show the instances yet.

3 files changed, 101 insertions, 41 deletions

diff --git a/src/Haddock/Interface/AttachInstances.hs b/src/Haddock/Interface/AttachInstances.hs
index aed832bb..38fef6b4 100644
--- a/src/Haddock/Interface/AttachInstances.hs
+++ b/src/Haddock/Interface/AttachInstances.hs
@@ -43,11 +43,12 @@ attachInstances modules filterNames = map attach modules
       where
         newItems = map attachExport (ifaceExportItems mod)
 
-        attachExport (ExportDecl n decl doc _) =
-          ExportDecl n decl doc (case Map.lookup n instMap of
-                                   Nothing -> []
-                                   Just instheads -> instheads)
-        attachExport otherExport = otherExport
+        attachExport (ExportDecl decl@(L _ (TyClD d)) doc _)
+          | isClassDecl d || isDataDecl d || isFamilyDecl d =
+             ExportDecl decl doc (case Map.lookup (tcdName d) instMap of
+                                    Nothing -> []
+                                    Just instheads -> instheads)
+        attachExport export = export
 
 
 --------------------------------------------------------------------------------
diff --git a/src/Haddock/Interface/Create.hs b/src/Haddock/Interface/Create.hs
index 24def155..7320af21 100644
--- a/src/Haddock/Interface/Create.hs
+++ b/src/Haddock/Interface/Create.hs
@@ -20,6 +20,7 @@ import Data.Maybe
 import Data.Char
 import Data.Ord
 import Control.Monad
+import Control.Arrow
 
 import GHC
 import Outputable
@@ -55,16 +56,18 @@ createInterface ghcMod flags modMap = do
       subMap        = mkSubMap group
       decls         = topDecls group
       declMap       = mkDeclMap decls
+      famMap        = Map.empty --mkFamMap decls
       ignoreExps    = Flag_IgnoreAllExports `elem` flags
       exportedNames = ghcExportedNames ghcMod
       origEnv       = Map.fromList [ (nameOccName n, n) | n <- exportedNames ]
+      instances     = ghcInstances ghcMod
 
   visibleNames <- mkVisibleNames mod modMap localNames 
                                  (ghcNamesInScope ghcMod) 
                                  subMap exports opts declMap 
 
-  exportItems <- mkExportItems modMap mod (ghcExportedNames ghcMod)
-                               decls declMap subMap opts exports ignoreExps
+  exportItems <- mkExportItems modMap mod (ghcExportedNames ghcMod)decls declMap
+                               famMap subMap opts exports ignoreExps instances
 
   -- prune the export list to just those declarations that have
   -- documentation, if the 'prune' option is on.
@@ -121,27 +124,51 @@ parseOption other = tell ["Unrecognised option: " ++ other] >> return Nothing
 
 
 --------------------------------------------------------------------------------
--- Extract declarations
+-- Declarations
 --------------------------------------------------------------------------------
 
+type DeclWithDoc = (LHsDecl Name, Maybe (HsDoc Name))
+
+
+-- | A list of type or data instance declarations with an optional family
+-- declaration.
+type Family = (Maybe DeclWithDoc, [DeclWithDoc])
+
 
 -- | Make a map from names to declarations with documentation. The map excludes
 -- all kinds of instance declarations (including type family instances) and
 -- documentation declarations.
 -- Subordinate names are mapped to the parent declaration, but with the doc
 -- for the subordinate declaration.
+mkDeclMap :: [DeclWithDoc] -> Map Name DeclWithDoc
 mkDeclMap decls = Map.fromList [ (n, (L loc d, doc)) | (L loc d, doc) <- decls 
                                , (n, doc) <- (declName d, doc) : subordinates d
-                               , notDocOrInstance d ]
+                               , not (isDoc d), not (isInstance d) ]
+
+
+-- | Group type family instances together. Include the family declaration
+-- if found.
+{-mkFamMap :: [DeclWithDoc] -> Map Name Family
+mkFamMap decls = 
+  Map.fromList [ (tcdName $ ex $ head $ g, family g) | g <- groups ]
+  where
+    family g = first listToMaybe $ partition (isFamilyDecl . ex) g
+    groups   = groupBy (comparing (tcdName . ex)) $ 
+               filter (isTyClD . unLoc . fst) decls
+    ex ((L _ (TyClD d)), _) = d
+-}
+
+isTyClD (TyClD _) = True
+isTyClD _ = False
+
+
+isDoc (DocD _) = True
+isDoc _ = False
 
 
-notDocOrInstance (InstD _) = False
-notDocOrInstance (TyClD (d@TyData {}))
-  | Just _ <- tcdTyPats d = False
-notDocOrInstance (TyClD (d@TySynonym {}))
-  | Just _ <- tcdTyPats d = False
-notDocOrInstance (DocD _) = False
-notDocOrInstance _        = True
+isInstance (InstD _) = True
+isInstance (TyClD d) = isFamInstDecl d
+isInstance _ = False
 
 
 subordinates (TyClD d) = classDataSubs d
@@ -184,9 +211,11 @@ declName (SigD sig) = fromJust $ sigNameNoLoc sig
 
 
 -- All the top-level declarations of a module, ordered by source location,
--- with documentation attached if it exists
-topDecls :: HsGroup Name -> [(LHsDecl Name, Maybe (HsDoc Name))] 
-topDecls = collectDocs . sortByLoc . declsFromGroup
+-- with documentation attached if it exists.
+-- TEMP hack to filter out all instances (we don't want them until
+-- rendering is completely implemented).
+topDecls :: HsGroup Name -> [DeclWithDoc] 
+topDecls = filter (\(L _ d, _) -> not (isInstance d)) . collectDocs . sortByLoc . declsFromGroup
 
 
 -- | Pick out the declarations that we want from a group
@@ -195,12 +224,13 @@ declsFromGroup group =
   decls hs_tyclds TyClD group ++
   decls hs_fords  ForD  group ++
   decls hs_docs   DocD  group ++
+  decls hs_instds InstD group ++
   decls (sigs . hs_valds) SigD group
   where
     sigs (ValBindsOut _ x) = x
 
 
--- | Takes a field of declarations from a data structure and creates HsDecls
+-- | Take a field of declarations from a data structure and create HsDecls
 -- using the given constructor
 decls field con struct = [ L loc (con decl) | L loc decl <- field struct ]
 
@@ -210,6 +240,19 @@ sortByLoc = sortBy (comparing getLoc)
 
 
 --------------------------------------------------------------------------------
+-- Instances
+--------------------------------------------------------------------------------
+
+{-
+matchingInsts :: Name -> [Instances] -> [Instances]
+matchingInsts name instances = filter ((==) name . is_cls) instances
+
+
+instToData :: Instance -> LHsDecl Name
+instToData inst = TyData {
+-}
+
+--------------------------------------------------------------------------------
 -- Collect docs
 --
 -- To be able to attach the right Haddock comment to the right declaration,
@@ -219,11 +262,11 @@ sortByLoc = sortBy (comparing getLoc)
 
 
 -- | Collect the docs and attach them to the right declaration
-collectDocs :: [LHsDecl Name] -> [(LHsDecl Name, Maybe (HsDoc Name))]
+collectDocs :: [LHsDecl Name] -> [DeclWithDoc]
 collectDocs decls = collect Nothing DocEmpty decls
 
 
-collect :: Maybe (LHsDecl Name) -> HsDoc Name -> [LHsDecl Name] -> [(LHsDecl Name, Maybe (HsDoc Name))]
+collect :: Maybe (LHsDecl Name) -> HsDoc Name -> [LHsDecl Name] -> [DeclWithDoc]
 collect d doc_so_far [] =
    case d of
         Nothing -> []
@@ -245,8 +288,7 @@ collect d doc_so_far (e:es) =
         | otherwise -> finishedDoc d0 doc_so_far (collect (Just e) DocEmpty es)
 
 
-finishedDoc :: LHsDecl Name -> HsDoc Name -> [(LHsDecl Name, Maybe (HsDoc Name))] -> 
-               [(LHsDecl Name, Maybe (HsDoc Name))]
+finishedDoc :: LHsDecl Name -> HsDoc Name -> [DeclWithDoc] -> [DeclWithDoc]
 finishedDoc d DocEmpty rest = (d, Nothing) : rest
 finishedDoc d doc rest | notDocDecl d = (d, Just doc) : rest
   where
@@ -257,7 +299,7 @@ finishedDoc _ _ rest = rest
 
 sameDecl d1 d2 = getLoc d1 == getLoc d2
 
-       
+
 mkSubMap :: HsGroup Name -> Map Name [Name]
 mkSubMap group = Map.fromList [ (name, subs) | L _ tycld <- hs_tyclds group,
  let name:subs = map unLoc (tyClDeclNames tycld) ]
@@ -270,29 +312,37 @@ mkExportItems
   :: ModuleMap
   -> Module			-- this module
   -> [Name]			-- exported names (orig)
-  -> [(LHsDecl Name, Maybe (HsDoc Name))]
-  -> Map Name (LHsDecl Name, Maybe (HsDoc Name)) -- maps local names to declarations
+  -> [DeclWithDoc]
+  -> Map Name DeclWithDoc -- maps local names to declarations
+  -> Map Name Family
   -> Map Name [Name]	-- sub-map for this module
   -> [DocOption]
   -> Maybe [IE Name]
   -> Bool				-- --ignore-all-exports flag
+  -> [Instance]
   -> ErrMsgM [ExportItem Name]
 
-mkExportItems modMap this_mod exported_names decls declMap sub_map
-              opts maybe_exps ignore_all_exports
+mkExportItems modMap this_mod exported_names decls declMap famMap sub_map
+              opts maybe_exps ignore_all_exports instances
   | isNothing maybe_exps || ignore_all_exports || OptIgnoreExports `elem` opts
     = everything_local_exported
-  | Just specs <- maybe_exps = do 
-      exps <- mapM lookupExport specs
-      return (concat exps)
+  | Just specs <- maybe_exps = liftM concat $ mapM lookupExport specs
   where
+    instances = [ d  | d@(L _ decl, _) <- decls, isInstance decl ]
+
     everything_local_exported =  -- everything exported
       return (fullContentsOfThisModule this_mod decls)
    
     packageId = modulePackageId this_mod
 
-    lookupExport (IEVar x)             = declWith x
-    lookupExport (IEThingAbs t)        = declWith t
+    lookupExport (IEVar x) = declWith x
+    lookupExport (IEThingAbs t) = declWith t
+  --    | Just fam <- Map.lookup t famMap = absFam fam
+  --    | otherwise = declWith t
+ --     where
+   --     absFam (Just (famDecl, doc), instances) = return $ [ ExportDecl famDecl doc [] ] ++ matchingInsts t
+     --   absFam (Nothing, instances) =
+
     lookupExport (IEThingAll t)        = declWith t
     lookupExport (IEThingWith t cs)    = declWith t
     lookupExport (IEModuleContents m)  = fullContentsOf (mkModule packageId m)
@@ -307,7 +357,7 @@ mkExportItems modMap this_mod exported_names decls declMap sub_map
     declWith :: Name -> ErrMsgM [ ExportItem Name ]
     declWith t
 	| Just (decl, maybeDoc) <- findDecl t
-        = return [ ExportDecl t (restrictTo subs (extractDecl t mdl decl)) maybeDoc [] ]
+        = return [ ExportDecl (restrictTo subs (extractDecl t mdl decl)) maybeDoc [] ]
 	| otherwise
 	= return []
 	where 
@@ -340,7 +390,7 @@ fullContentsOfThisModule :: Module -> [(LHsDecl Name, Maybe (HsDoc Name))] -> [E
 fullContentsOfThisModule module_ decls = catMaybes (map mkExportItem decls)
   where
     mkExportItem (L _ (DocD (DocGroup lev doc)), _) = Just $ ExportGroup lev "" doc
-    mkExportItem (decl, doc) = Just $ ExportDecl (declName (unLoc decl)) decl doc []
+    mkExportItem (decl, doc) = Just $ ExportDecl decl doc []
 --    mkExportItem _ = Nothing -- TODO: see if this is really needed
 
 
@@ -407,7 +457,7 @@ extractRecSel nm mdl t tvs (L _ con : rest) =
 -- Pruning
 pruneExportItems :: [ExportItem Name] -> [ExportItem Name]
 pruneExportItems items = filter hasDoc items
-  where hasDoc (ExportDecl _ _ d _) = isJust d
+  where hasDoc (ExportDecl _ d _) = isJust d
 	hasDoc _ = True
 
 
diff --git a/src/Haddock/Interface/Rename.hs b/src/Haddock/Interface/Rename.hs
index f6ffd7ab..d9488ac2 100644
--- a/src/Haddock/Interface/Rename.hs
+++ b/src/Haddock/Interface/Rename.hs
@@ -292,6 +292,9 @@ renameDecl d = case d of
   ForD d -> do
     d' <- renameForD d
     return (ForD d')
+  InstD d -> do
+    d' <- renameInstD d
+    return (InstD d')
   _ -> error "renameDecl"
 
 
@@ -318,11 +321,11 @@ renameTyClD d = case d of
     return (TyData x lcontext' lname' ltyvars' typats' k cons' Nothing) 
  
   TySynonym lname ltyvars typats ltype -> do
+    lname'   <- renameL lname
     ltyvars' <- mapM renameLTyVarBndr ltyvars
     ltype'   <- renameLType ltype
     typats'  <- mapM (mapM renameLType) typats
-    -- We skip type patterns here as well.
-    return (TySynonym (keepL lname) ltyvars' typats' ltype')
+    return (TySynonym lname' ltyvars' typats' ltype')
 
   ClassDecl lcontext lname ltyvars lfundeps lsigs _ ats _ -> do
     lcontext' <- renameLContext lcontext
@@ -379,17 +382,23 @@ renameForD (ForeignExport lname ltype x) = do
   return (ForeignExport (keepL lname) ltype' x)
 
 
+renameInstD (InstDecl ltype _ _ lATs) = do
+  ltype <- renameLType ltype
+  lATs' <- mapM renameLTyClD lATs
+  return (InstDecl ltype emptyBag [] lATs') 
+
+
 renameExportItem :: ExportItem Name -> RnM (ExportItem DocName)
 renameExportItem item = case item of 
   ExportModule mod -> return (ExportModule mod)
   ExportGroup lev id doc -> do
     doc' <- renameDoc doc
     return (ExportGroup lev id doc')
-  ExportDecl x decl doc instances -> do
+  ExportDecl decl doc instances -> do
     decl' <- renameLDecl decl
     doc'  <- mapM renameDoc doc
     instances' <- mapM renameInstHead instances
-    return (ExportDecl x decl' doc' instances')
+    return (ExportDecl decl' doc' instances')
   ExportNoDecl x y subs -> do
     y'    <- lookupRn id y
     subs' <- mapM (lookupRn id) subs