GHC.Tc.TyCl.Utils

Analysis functions over data types. Specifically, detecting recursive types.

This stuff is only used for source-code decls; it's recorded in interface files for imported data types.

Documentation

type RolesInfo = Name -> [Role]

inferRoles :: HscSource -> RoleAnnotEnv -> [TyCon] -> Name -> [Role]

checkSynCycles :: Unit -> [TyCon] -> [LTyClDecl GhcRn] -> TcM ()

Checks if any of the passed in TyCons have cycles. Takes the Unit of the home package (as we can avoid checking those TyCons: cycles never go through foreign packages) and the corresponding LTyClDecl Name for each TyCon, so we can give better error messages.

checkClassCycles :: Class -> Maybe SDoc

Implicits

addTyConsToGblEnv :: [TyCon] -> TcM (TcGblEnv, ThBindEnv)

mkDefaultMethodType :: Class -> Id -> DefMethSpec Type -> Type

Record selectors

tcRecSelBinds :: [(Id, LHsBind GhcRn)] -> TcM TcGblEnv

mkRecSelBinds :: [TyCon] -> [(Id, LHsBind GhcRn)]

mkOneRecordSelector :: [ConLike] -> RecSelParent -> FieldLabel -> FieldSelectors -> (Id, LHsBind GhcRn)