\begin{code}
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-buildSynTyCon :: Name -> [TyVar] -> SynTyConRhs -> TyCon
-buildSynTyCon name tvs rhs@(OpenSynTyCon rhs_ki)
- = mkSynTyCon name kind tvs rhs
- where
- kind = mkArrowKinds (map tyVarKind tvs) rhs_ki
-buildSynTyCon name tvs rhs@(SynonymTyCon rhs_ty)
- = mkSynTyCon name kind tvs rhs
- where
- kind = mkArrowKinds (map tyVarKind tvs) (typeKind rhs_ty)
+buildSynTyCon :: Name -> [TyVar]
+ -> SynTyConRhs
+ -> Maybe (TyCon, [Type]) -- family instance if applicable
+ -> TcRnIf m n TyCon
+buildSynTyCon tc_name tvs rhs@(OpenSynTyCon rhs_ki _) _
+ = let
+ kind = mkArrowKinds (map tyVarKind tvs) rhs_ki
+ in
+ return $ mkSynTyCon tc_name kind tvs rhs NoParentTyCon
+
+buildSynTyCon tc_name tvs rhs@(SynonymTyCon rhs_ty) mb_family
+ = do { -- We need to tie a knot as the coercion of a data instance depends
+ -- on the instance representation tycon and vice versa.
+ ; tycon <- fixM (\ tycon_rec -> do
+ { parent <- mkParentInfo mb_family tc_name tvs tycon_rec
+ ; let { tycon = mkSynTyCon tc_name kind tvs rhs parent
+ ; kind = mkArrowKinds (map tyVarKind tvs) (typeKind rhs_ty)
+ }
+ ; return tycon
+ })
+ ; return tycon
+ }
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buildAlgTyCon :: Name -> [TyVar]
= do { -- We need to tie a knot as the coercion of a data instance depends
-- on the instance representation tycon and vice versa.
; tycon <- fixM (\ tycon_rec -> do
- { parent <- parentInfo mb_family tycon_rec
+ { parent <- mkParentInfo mb_family tc_name tvs tycon_rec
; let { tycon = mkAlgTyCon tc_name kind tvs stupid_theta rhs
fields parent is_rec want_generics gadt_syn
; kind = mkArrowKinds (map tyVarKind tvs) liftedTypeKind
})
; return tycon
}
- where
- -- If a family tycon with instance types is given, the current tycon is an
- -- instance of that family and we need to
- --
- -- (1) create a coercion that identifies the family instance type and the
- -- representation type from Step (1); ie, it is of the form
- -- `Co tvs :: F ts :=: R tvs', where `Co' is the name of the coercion,
- -- `F' the family tycon and `R' the (derived) representation tycon,
- -- and
- -- (2) produce a `AlgTyConParent' value containing the parent and coercion
- -- information.
- --
- parentInfo Nothing rep_tycon =
- return NoParentTyCon
- parentInfo (Just (family, instTys)) rep_tycon =
- do { -- Create the coercion
- ; co_tycon_name <- newImplicitBinder tc_name mkInstTyCoOcc
- ; let co_tycon = mkDataInstCoercion co_tycon_name tvs
- family instTys rep_tycon
- ; return $ FamilyTyCon family instTys co_tycon
- }
-
+-- If a family tycon with instance types is given, the current tycon is an
+-- instance of that family and we need to
+--
+-- (1) create a coercion that identifies the family instance type and the
+-- representation type from Step (1); ie, it is of the form
+-- `Co tvs :: F ts :=: R tvs', where `Co' is the name of the coercion,
+-- `F' the family tycon and `R' the (derived) representation tycon,
+-- and
+-- (2) produce a `TyConParent' value containing the parent and coercion
+-- information.
+--
+mkParentInfo :: Maybe (TyCon, [Type])
+ -> Name -> [TyVar]
+ -> TyCon
+ -> TcRnIf m n TyConParent
+mkParentInfo Nothing _ _ _ =
+ return NoParentTyCon
+mkParentInfo (Just (family, instTys)) tc_name tvs rep_tycon =
+ do { -- Create the coercion
+ ; co_tycon_name <- newImplicitBinder tc_name mkInstTyCoOcc
+ ; let co_tycon = mkFamInstCoercion co_tycon_name tvs
+ family instTys rep_tycon
+ ; return $ FamilyTyCon family instTys co_tycon
+ }
+
------------------------------------------------------
mkAbstractTyConRhs :: AlgTyConRhs
mkAbstractTyConRhs = AbstractTyCon
mkOpenDataTyConRhs :: AlgTyConRhs
-mkOpenDataTyConRhs = OpenDataTyCon
+mkOpenDataTyConRhs = OpenTyCon Nothing False
mkOpenNewTyConRhs :: AlgTyConRhs
-mkOpenNewTyConRhs = OpenNewTyCon
+mkOpenNewTyConRhs = OpenTyCon Nothing True
mkDataTyConRhs :: [DataCon] -> AlgTyConRhs
mkDataTyConRhs cons