Mon Nov 20 20:51:39 UTC 2017

Repository : ssh://git@git.haskell.org/haddock

On branches: 2.17.3.1-spanfix,alexbiehl-patch-1,ghc-8.0,ghc-8.0-facebook,ghc-head,ghc-head1,haddock-quick,headdock-library-1.4.5,ie_avails,issue-303,issue-475,master,pr-filter-maps,pr/cabal-desc,travis,v2.16,v2.17,v2.17.3,v2.18,wip-located-module-as,wip/D2418,wip/T11080-open-data-kinds,wip/T11258,wip/T11430,wip/T12105,wip/T12105-2,wip/T12942,wip/T13163,wip/T3384,wip/embelleshed-rdr,wip/new-tree-one-param,wip/rae,wip/remove-frames,wip/remove-frames1,wip/revert-ttg-2017-11-20,wip/ttg-2017-10-13,wip/ttg-2017-10-31,wip/ttg-2017-11-06,wip/ttg2-2017-11-10,wip/ttg3-2017-11-12,wip/ttg4-constraints-2017-11-13
Link       : http://git.haskell.org/haddock.git/commitdiff/de395700afa73065a2ec69ba5e3cc3ec1a474d11

>---------------------------------------------------------------

commit de395700afa73065a2ec69ba5e3cc3ec1a474d11
Author: Łukasz Hanuszczak <lukasz.hanuszczak at gmail.com>
Date:   Wed Jul 29 15:13:26 2015 +0200

    Introduce alternative type for family declarations.


>---------------------------------------------------------------

de395700afa73065a2ec69ba5e3cc3ec1a474d11
 haddock-api/src/Haddock/Types.hs | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/haddock-api/src/Haddock/Types.hs b/haddock-api/src/Haddock/Types.hs
index ac07303..90672c9 100644
--- a/haddock-api/src/Haddock/Types.hs
+++ b/haddock-api/src/Haddock/Types.hs
@@ -341,6 +341,37 @@ instance OutputableBndr a => Outputable (InstType a) where
   ppr (TypeInst  a) = text "TypeInst"  <+> ppr a
   ppr (DataInst  a) = text "DataInst"  <+> ppr a
 
+
+-- | Almost the same as 'FamilyDecl' except for type binders.
+--
+-- In order to perform type specialization for class instances, we need to
+-- substitute class variables to appropriate type. However, type variables in
+-- associated type are specified using 'LHsTyVarBndrs' instead of 'HsType'.
+-- This makes type substitution impossible and to overcome this issue,
+-- 'PseudoFamilyDecl' type is introduced.
+data PseudoFamilyDecl name = PseudoFamilyDecl
+    { pfdInfo :: FamilyInfo name
+    , pfdLName :: Located name
+    , pfdTyVars :: [LHsType name]
+    , pfdKindSig :: Maybe (LHsKind name)
+    }
+
+
+mkPseudoFamilyDecl :: FamilyDecl name -> PseudoFamilyDecl name
+mkPseudoFamilyDecl (FamilyDecl { .. }) = PseudoFamilyDecl
+    { pfdInfo = fdInfo
+    , pfdLName = fdLName
+    , pfdTyVars = [ L loc (mkType bndr) | L loc bndr <- hsq_tvs fdTyVars ]
+    , pfdKindSig = fdKindSig
+    }
+  where
+    mkType (KindedTyVar (L loc name) lkind) =
+        HsKindSig tvar lkind
+      where
+        tvar = L loc (HsTyVar name)
+    mkType (UserTyVar name) = HsTyVar name
+
+
 -- | An instance head that may have documentation and a source location.
 type DocInstance name = (InstHead name, Maybe (MDoc name), Located name)
 

