aux test_eq_only ((name1, C.Decl s1)::context) t1 t2
| (C.LetIn (name1,ty1,s1,t1), C.LetIn(_,ty2,s2,t2)) ->
aux test_eq_only context ty1 ty2 &&
aux test_eq_only ((name1, C.Decl s1)::context) t1 t2
| (C.LetIn (name1,ty1,s1,t1), C.LetIn(_,ty2,s2,t2)) ->
aux test_eq_only context ty1 ty2 &&