static void ai_silentlyInvalidateAndDeleteTriple(S a, S b, S c) {
  ai_silentlyInvalidateAndDeleteTriple(ai_findTriple(a, b, c));
}

static void ai_silentlyInvalidateAndDeleteTriple(TripleWeb t) {
  if (t == null) ret;
  ai_deleteTriple(ai_invalidateTriple(t));
  ai_deleteTriple(t);
}