import FamInst
import FamInstEnv
-import NameSet ( addOneToNameSet )
-
import qualified TcRnMonad as TcM
import qualified TcMType as TcM
import qualified TcEnv as TcM
( checkWellStaged, topIdLvl, tcLookupFamInst, tcGetDefaultTys )
import TcType
-import Module
import DynFlags
import Coercion
text "witness" <+> ppr dfun_id
<+> ppr (idType dfun_id) ])
-- Record that this dfun is needed
- ; record_dfun_usage dfun_id
- ; return $ MatchInstSingle (dfun_id, inst_tys)
+ ; return $ MatchInstSingle (dfun_id, inst_tys)
} ;
(matches, unifs) -- More than one matches
-> do { traceTcS "matchClass multiple matches, deferring choice"
}
}
}
- where record_dfun_usage :: Id -> TcS ()
- record_dfun_usage dfun_id
- = do { hsc_env <- getTopEnv
- ; let dfun_name = idName dfun_id
- dfun_mod = ASSERT( isExternalName dfun_name )
- nameModule dfun_name
- ; if isInternalName dfun_name || -- Internal name => defined in this module
- modulePackageId dfun_mod /= thisPackage (hsc_dflags hsc_env)
- then return () -- internal, or in another package
- else do updInstUses dfun_id
- }
-
- updInstUses :: Id -> TcS ()
- updInstUses dfun_id
- = do { tcg_env <- getGblEnv
- ; wrapTcS $ TcM.updMutVar (tcg_inst_uses tcg_env)
- (`addOneToNameSet` idName dfun_id)
- }
-
-matchFam :: TyCon
+
+matchFam :: TyCon
-> [Type]
-> TcS (MatchInstResult (TyCon, [Type]))
matchFam tycon args