diff options
Diffstat (limited to 'compiler/GHC/Core/Class.hs')
| -rw-r--r-- | compiler/GHC/Core/Class.hs | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/compiler/GHC/Core/Class.hs b/compiler/GHC/Core/Class.hs index f5d24aaf3c..57e6defca6 100644 --- a/compiler/GHC/Core/Class.hs +++ b/compiler/GHC/Core/Class.hs @@ -8,7 +8,7 @@ module GHC.Core.Class ( Class, ClassOpItem, - ClassATItem(..), + ClassATItem(..), ATValidityInfo(..), ClassMinimalDef, DefMethInfo, pprDefMethInfo, @@ -97,10 +97,21 @@ type DefMethInfo = Maybe (Name, DefMethSpec Type) data ClassATItem = ATI TyCon -- See Note [Associated type tyvar names] - (Maybe (Type, SrcSpan)) + (Maybe (Type, ATValidityInfo)) -- Default associated type (if any) from this template -- Note [Associated type defaults] +-- | Information about an associated type family default implementation. This +-- is used solely for validity checking. +-- See @Note [Type-checking default assoc decls]@ in "GHC.Tc.TyCl". +data ATValidityInfo + = NoATVI -- Used for associated type families that are imported + -- from another module, for which we don't need to + -- perform any validity checking. + + | ATVI SrcSpan [Type] -- Used for locally defined associated type families. + -- The [Type] are the LHS patterns. + type ClassMinimalDef = BooleanFormula Name -- Required methods data ClassBody |