-tcDefaults [DefaultDecl mono_tys locn]
- = tcLookupGlobal_maybe numClassName `thenM` \ maybe_num ->
- case maybe_num of
- Just (AClass num_class) -> common_case num_class
- other -> returnM []
- -- In the Nothing case, Num has not been sucked in, so the
- -- defaults will never be used; so simply discard the default decl.
- -- This slightly benefits modules that don't use any
- -- numeric stuff at all, by avoid the necessity of
- -- always sucking in Num
- where
- common_case num_class
- = addSrcLoc locn $
- addErrCtxt defaultDeclCtxt $
- mappM tc_default_ty mono_tys `thenM` \ tau_tys ->
+tcDefaults [L locn (DefaultDecl mono_tys)]
+ = setSrcSpan locn $
+ addErrCtxt defaultDeclCtxt $
+ tcLookupClass numClassName `thenM` \ num_class ->
+ mappM tc_default_ty mono_tys `thenM` \ tau_tys ->