+ with Invalid_argument "List.for_all2" ->
+ prerr_endline ("Meta " ^ string_of_int n1 ^
+ " occurrs with local contexts of different lenght\n"^
+ NCicPp.ppterm ~metasenv ~subst ~context t1 ^ " === " ^
+ NCicPp.ppterm ~metasenv ~subst ~context t2);
+ assert false) -> true