- { L (comb4 $1 $2 $4 $5)
- (mkTyData (unLoc $1) (unLoc $2) $3
- (reverse (unLoc $5)) (unLoc $6)) }
-
-opt_iso :: { Bool }
- : { False }
- | 'iso' { True }
-
-kind_or_ctype :: { Either (Located (Maybe Kind)) (LHsType RdrName) }
- : { Left (noLoc Nothing) }
- | '::' kind { Left (LL (Just (unLoc $2))) }
- | '=' ctype { Right (LL (unLoc $2)) }
- -- Note ctype, not sigtype, on the right of '='
- -- We allow an explicit for-all but we don't insert one
- -- in type Foo a = (b,b)
- -- Instead we just say b is out of scope
+ {% mkTyData (comb4 $1 $2 $4 $5) (unLoc $1) False $2
+ (unLoc $3) (unLoc $4) (unLoc $5) }
+ -- We need the location on tycl_hdr in case
+ -- constrs and deriving are both empty
+
+ -- data/newtype family
+ | 'data' 'family' type opt_kind_sig
+ {% mkTyFamily (comb3 $1 $2 $4) DataFamily $3 (unLoc $4) }
+
+ -- data/newtype instance declaration
+ | data_or_newtype 'instance' tycl_hdr constrs deriving
+ {% mkTyData (comb4 $1 $3 $4 $5) (unLoc $1) True $3
+ Nothing (reverse (unLoc $4)) (unLoc $5) }
+
+ -- GADT instance declaration
+ | data_or_newtype 'instance' tycl_hdr opt_kind_sig
+ gadt_constrlist
+ deriving
+ {% mkTyData (comb4 $1 $3 $5 $6) (unLoc $1) True $3
+ (unLoc $4) (unLoc $5) (unLoc $6) }
+
+-- Associated type family declarations
+--
+-- * They have a different syntax than on the toplevel (no family special
+-- identifier).
+--
+-- * They also need to be separate from instances; otherwise, data family
+-- declarations without a kind signature cause parsing conflicts with empty
+-- data declarations.
+--
+at_decl_cls :: { LTyClDecl RdrName }
+ -- type family declarations
+ : 'type' type opt_kind_sig
+ -- Note the use of type for the head; this allows
+ -- infix type constructors to be declared
+ {% mkTyFamily (comb3 $1 $2 $3) TypeFamily $2 (unLoc $3) }
+
+ -- default type instance
+ | 'type' type '=' ctype
+ -- Note the use of type for the head; this allows
+ -- infix type constructors and type patterns
+ {% mkTySynonym (comb2 $1 $4) True $2 $4 }
+
+ -- data/newtype family declaration
+ | 'data' type opt_kind_sig
+ {% mkTyFamily (comb3 $1 $2 $3) DataFamily $2 (unLoc $3) }
+
+-- Associated type instances
+--
+at_decl_inst :: { LTyClDecl RdrName }
+ -- type instance declarations
+ : 'type' type '=' ctype
+ -- Note the use of type for the head; this allows
+ -- infix type constructors and type patterns
+ {% mkTySynonym (comb2 $1 $4) True $2 $4 }
+
+ -- data/newtype instance declaration
+ | data_or_newtype tycl_hdr constrs deriving
+ {% mkTyData (comb4 $1 $2 $3 $4) (unLoc $1) True $2
+ Nothing (reverse (unLoc $3)) (unLoc $4) }
+
+ -- GADT instance declaration
+ | data_or_newtype tycl_hdr opt_kind_sig
+ gadt_constrlist
+ deriving
+ {% mkTyData (comb4 $1 $2 $4 $5) (unLoc $1) True $2
+ (unLoc $3) (unLoc $4) (unLoc $5) }