Refactor instance head type to record instead of a meaningless tuple.

6 files changed, 63 insertions, 38 deletions

diff --git a/haddock-api/src/Haddock/Backends/LaTeX.hs b/haddock-api/src/Haddock/Backends/LaTeX.hs
index 2febd5ae..59e5af3e 100644
--- a/haddock-api/src/Haddock/Backends/LaTeX.hs
+++ b/haddock-api/src/Haddock/Backends/LaTeX.hs
@@ -1,4 +1,5 @@
 {-# OPTIONS_GHC -fno-warn-name-shadowing #-}
+{-# LANGUAGE RecordWildCards #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Haddock.Backends.LaTeX
@@ -560,12 +561,13 @@ ppInstDecl unicode instHead = keyword "instance" <+> ppInstHead unicode instHead
 
 
 ppInstHead :: Bool -> InstHead DocName -> LaTeX
-ppInstHead unicode (n, ks, ts, ClassInst ctx) = ppContextNoLocs ctx unicode <+> ppAppNameTypes n ks ts unicode
-ppInstHead unicode (n, ks, ts, TypeInst rhs) = keyword "type"
-  <+> ppAppNameTypes n ks ts unicode
-  <+> maybe empty (\t -> equals <+> ppType unicode t) rhs
-ppInstHead _unicode (_n, _ks, _ts, DataInst _dd) =
-  error "data instances not supported by --latex yet"
+ppInstHead unicode (InstHead {..}) = case ihdInstType of
+    ClassInst ctx -> ppContextNoLocs ctx unicode <+> typ
+    TypeInst rhs -> keyword "type" <+> typ <+> tibody rhs
+    DataInst _ -> error "data instances not supported by --latex yet"
+  where
+    typ = ppAppNameTypes ihdClsName ihdKinds ihdTypes unicode
+    tibody = maybe empty (\t -> equals <+> ppType unicode t)
 
 lookupAnySubdoc :: (Eq name1) =>
                    name1 -> [(name1, DocForDecl name2)] -> DocForDecl name2
diff --git a/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs b/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
index a5f3676e..afbbaad1 100644
--- a/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
+++ b/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE TransformListComp #-}
+{-# LANGUAGE RecordWildCards #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Haddock.Backends.Html.Decl
@@ -507,15 +508,21 @@ ppInstances links instances _ baseName unicode qual
   where
     instName = getOccString $ getName baseName
     instDecl :: DocInstance DocName -> (SubDecl,Located DocName)
-    instDecl (inst, maybeDoc,l) = ((instHead inst, maybeDoc, []),l)
-    instHead (n, ks, ts, ClassInst cs) = ppContextNoLocs cs unicode qual
-        <+> ppAppNameTypes n ks ts unicode qual
-    instHead (n, ks, ts, TypeInst rhs) = keyword "type"
-        <+> ppAppNameTypes n ks ts unicode qual
+    instDecl (inst, maybeDoc,l) =
+        ((ppInstHead links unicode qual inst, maybeDoc, []),l)
+
+ppInstHead :: LinksInfo -> Unicode -> Qualification
+           -> InstHead DocName
+           -> Html
+ppInstHead _ unicode qual (InstHead {..}) = case ihdInstType of
+    ClassInst cs -> ppContextNoLocs cs unicode qual <+> typ
+    TypeInst rhs -> keyword "type" <+> typ
         <+> maybe noHtml (\t -> equals <+> ppType unicode qual t) rhs
-    instHead (n, ks, ts, DataInst dd) = keyword "data"
-        <+> ppAppNameTypes n ks ts unicode qual
+    DataInst dd -> keyword "data" <+> typ
         <+> ppShortDataDecl False True dd unicode qual
+  where
+    typ = ppAppNameTypes ihdClsName ihdKinds ihdTypes unicode qual
+
 
 lookupAnySubdoc :: Eq id1 => id1 -> [(id1, DocForDecl id2)] -> DocForDecl id2
 lookupAnySubdoc n = fromMaybe noDocForDecl . lookup n
diff --git a/haddock-api/src/Haddock/Convert.hs b/haddock-api/src/Haddock/Convert.hs
index 5cbf5f97..e51d9df7 100644
--- a/haddock-api/src/Haddock/Convert.hs
+++ b/haddock-api/src/Haddock/Convert.hs
@@ -390,23 +390,29 @@ synifyKindSig :: Kind -> LHsKind Name
 synifyKindSig k = synifyType WithinType k
 
 synifyInstHead :: ([TyVar], [PredType], Class, [Type]) -> InstHead Name
-synifyInstHead (_, preds, cls, types) =
-  ( getName cls
-  , map (unLoc . synifyType WithinType) ks
-  , map (unLoc . synifyType WithinType) ts
-  , ClassInst $ map (unLoc . synifyType WithinType) preds
-  )
+synifyInstHead (_, preds, cls, types) = InstHead
+  { ihdClsName = getName cls
+  , ihdKinds = map (unLoc . synifyType WithinType) ks
+  , ihdTypes = map (unLoc . synifyType WithinType) ts
+  , ihdInstType = ClassInst $ map (unLoc . synifyType WithinType) preds
+  }
   where (ks,ts) = break (not . isKind) types
 
 -- Convert a family instance, this could be a type family or data family
 synifyFamInst :: FamInst -> Bool -> Either ErrMsg (InstHead Name)
-synifyFamInst fi opaque =
-  let fff = case fi_flavor fi of
-        SynFamilyInst | opaque -> return $ TypeInst Nothing
-        SynFamilyInst ->
-          return . TypeInst . Just . unLoc . synifyType WithinType $ fi_rhs fi
-        DataFamilyInst c ->
-          synifyTyCon (Just $ famInstAxiom fi) c >>= return . DataInst
-  in fff >>= \f' -> return (fi_fam fi , map (unLoc . synifyType WithinType) ks,
-                            map (unLoc . synifyType WithinType) ts , f')
-  where (ks,ts) = break (not . isKind) $ fi_tys fi
+synifyFamInst fi opaque = do
+    ityp' <- ityp $ fi_flavor fi
+    return InstHead
+        { ihdClsName = fi_fam fi
+        , ihdKinds = synifyTypes ks
+        , ihdTypes = synifyTypes ts
+        , ihdInstType = ityp'
+        }
+  where
+    ityp SynFamilyInst | opaque = return $ TypeInst Nothing
+    ityp SynFamilyInst =
+        return . TypeInst . Just . unLoc . synifyType WithinType $ fi_rhs fi
+    ityp (DataFamilyInst c) =
+        DataInst <$> synifyTyCon (Just $ famInstAxiom fi) c
+    (ks,ts) = break (not . isKind) $ fi_tys fi
+    synifyTypes = map (unLoc. synifyType WithinType)
diff --git a/haddock-api/src/Haddock/Interface/AttachInstances.hs b/haddock-api/src/Haddock/Interface/AttachInstances.hs
index fc530507..e2fd24ee 100644
--- a/haddock-api/src/Haddock/Interface/AttachInstances.hs
+++ b/haddock-api/src/Haddock/Interface/AttachInstances.hs
@@ -108,7 +108,7 @@ attachToExportItem expInfo iface ifaceMap instIfaceMap export =
 
     attachFixities e = e
     -- spanName: attach the location to the name that is the same file as the instance location
-    spanName s (clsn,_,_,_) (L instL instn) =
+    spanName s (InstHead { ihdClsName = clsn }) (L instL instn) =
         let s1 = getSrcSpan s
             sn = if srcSpanFileName_maybe s1 == srcSpanFileName_maybe instL
                     then instn
diff --git a/haddock-api/src/Haddock/Interface/Rename.hs b/haddock-api/src/Haddock/Interface/Rename.hs
index 1a559764..d222c6d2 100644
--- a/haddock-api/src/Haddock/Interface/Rename.hs
+++ b/haddock-api/src/Haddock/Interface/Rename.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE RecordWildCards #-}
 ----------------------------------------------------------------------------
 -- |
 -- Module      :  Haddock.Interface.Rename
@@ -261,16 +262,20 @@ renameLContext (L loc context) = do
   return (L loc context')
 
 renameInstHead :: InstHead Name -> RnM (InstHead DocName)
-renameInstHead (className, k, types, rest) = do
-  className' <- rename className
-  k' <- mapM renameType k
-  types' <- mapM renameType types
-  rest' <- case rest of
+renameInstHead InstHead {..} = do
+  cname <- rename ihdClsName
+  kinds <- mapM renameType ihdKinds
+  types <- mapM renameType ihdTypes
+  itype <- case ihdInstType of
     ClassInst cs -> ClassInst <$> mapM renameType cs
     TypeInst  ts -> TypeInst  <$> traverse renameType ts
     DataInst  dd -> DataInst  <$> renameTyClD dd
-  return (className', k', types', rest')
-
+  return InstHead
+    { ihdClsName = cname
+    , ihdKinds = kinds
+    , ihdTypes = types
+    , ihdInstType = itype
+    }
 
 renameLDecl :: LHsDecl Name -> RnM (LHsDecl DocName)
 renameLDecl (L loc d) = return . L loc =<< renameDecl d
diff --git a/haddock-api/src/Haddock/Types.hs b/haddock-api/src/Haddock/Types.hs
index 6dd64506..d9ae6cab 100644
--- a/haddock-api/src/Haddock/Types.hs
+++ b/haddock-api/src/Haddock/Types.hs
@@ -308,7 +308,12 @@ type DocInstance name = (InstHead name, Maybe (MDoc name), Located name)
 
 -- | The head of an instance. Consists of a class name, a list of kind
 -- parameters, a list of type parameters and an instance type
-type InstHead name = (name, [HsType name], [HsType name], InstType name)
+data InstHead name = InstHead
+    { ihdClsName :: name
+    , ihdKinds :: [HsType name]
+    , ihdTypes :: [HsType name]
+    , ihdInstType :: InstType name
+    }
 
 -----------------------------------------------------------------------------
 -- * Documentation comments