mk_eqn_help loc orig gla_exts new_or_data tycon deriv_tvs clas tys
------------------------------------------------------------------
- mk_eqn_help gla_exts DataType tycon deriv_tvs clas tys
+ -- data/newtype T a = ... deriving( C t1 t2 )
+ -- leads to a call to mk_eqn_help with
+ -- tycon = T, deriv_tvs = ftv(t1,t2), clas = C, tys = [t1,t2]
+
+ mk_eqn_help loc orig gla_exts DataType tycon deriv_tvs clas tys
| Just err <- checkSideConditions gla_exts tycon deriv_tvs clas tys
= bale_out (derivingThingErr clas tys tycon (tyConTyVars tycon) err)
| otherwise