let
prag_fn = mkPragFun uprags
all_insts = avail_insts ++ catMaybes meth_insts
- tc_method_bind = tcMethodBind inst_tyvars' dfun_theta' all_insts prag_fn
+ sig_fn n = Just [] -- No scoped type variables, but every method has
+ -- a type signature, in effect, so that we check
+ -- the method has the right type
+ tc_method_bind = tcMethodBind inst_tyvars' dfun_theta' all_insts sig_fn prag_fn
meth_ids = [meth_id | (_,meth_id,_) <- meth_infos]
in