X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fiface%2FBuildTyCl.lhs;h=6384ddc4c504f9c4079eec2f093a6a9e24a2191c;hb=f06f40fb77bc67e87cbb5e7b8b3fca9a18c7a905;hp=5f23fd5fb4e5b8b8aae7533be3d0d9639de25806;hpb=909d2dd885f5eebaf7c12cf15d5ac153d646566e;p=ghc-hetmet.git diff --git a/compiler/iface/BuildTyCl.lhs b/compiler/iface/BuildTyCl.lhs index 5f23fd5..6384ddc 100644 --- a/compiler/iface/BuildTyCl.lhs +++ b/compiler/iface/BuildTyCl.lhs @@ -69,8 +69,7 @@ buildAlgTyCon :: Name -> [TyVar] -> RecFlag -> Bool -- True <=> want generics functions -> Bool -- True <=> was declared in GADT syntax - -> Maybe (TyCon, [Type]) -- Just (family, tys) - -- <=> instance of `family' at `tys' + -> Maybe (TyCon, [Type]) -- family instance if applicable -> TcRnIf m n TyCon buildAlgTyCon tc_name tvs stupid_theta rhs is_rec want_generics gadt_syn @@ -78,8 +77,8 @@ buildAlgTyCon tc_name tvs stupid_theta rhs is_rec want_generics gadt_syn = 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 - { (final_name, parent) <- maybeComputeFamilyInfo mb_family tycon_rec - ; let { tycon = mkAlgTyCon final_name kind tvs stupid_theta rhs + { parent <- parentInfo mb_family 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 ; fields = mkTyConSelIds tycon rhs @@ -90,32 +89,24 @@ buildAlgTyCon tc_name tvs stupid_theta rhs is_rec want_generics gadt_syn } where -- If a family tycon with instance types is given, the current tycon is an - -- instance of that family and we have to perform three extra tasks: + -- instance of that family and we need to -- - -- (1) The instance tycon (representing the family at a particular type - -- instance) need to get a new, derived name - we may not reuse the - -- family name. - -- (2) Create a coercion that identifies the family instance type and the + -- (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. - -- (3) Produce a `AlgTyConParent' value containing the parent and coercion + -- `F' the family tycon and `R' the (derived) representation tycon, + -- and + -- (2) produce a `AlgTyConParent' value containing the parent and coercion -- information. -- - maybeComputeFamilyInfo Nothing rep_tycon = - return (tc_name, NoParentTyCon) - maybeComputeFamilyInfo (Just (family, instTys)) rep_tycon = - do { -- (1) New, derived name for the instance tycon - ; uniq <- newUnique - ; final_name <- newImplicitBinder tc_name (mkInstTyTcOcc uniq) - - -- (2) Create the coercion. - ; co_tycon_name <- newImplicitBinder tc_name (mkInstTyCoOcc uniq) + 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 - - -- (3) Produce parent information. - ; return (final_name, FamilyTyCon family instTys co_tycon) + ; return $ FamilyTyCon family instTys co_tycon }