sbool flexMatchIC_iterate_debug;
sbool flexMatchIC_iterate_useTokenization = true;

svoid flexMatchIC_iterate(S pat, S input, VF1<Matches> onMatch, O... _) {
  if (flexMatchIC_iterate_debug)
    print("flexMatchIC_iterate " + pat + " / " + input);
  optPar IF1<S, LS> tokenizer = lambda1 javaTokNPunctuation_plusAsterisk;
  flexMatchIC_iterate(pat,
    callTokenizer(tokenizer, pat),
    callTokenizer(tokenizer, input),
    onMatch, _);
}

svoid flexMatchIC_iterate(S pat, LS tokPat, LS tokInput, VF1<Matches> onMatch, O... _) {
  L<Int> varIndices = flexMatchIC_getVarIndices(tokPat, tokInput);
  if (varIndices == null) ret;
  if (flexMatchIC_iterate_debug)
    printStructs(+varIndices, +tokPat, +tokInput);
  ItIt<L<S>> spreadInputs = ai_spreadCertainIndices_2_iterator(tokPat, tokInput, varIndices);
  for (LS tok : spreadInputs) {
    if (flexMatchIC_iterate_debug)
      print("Testing spread " + sfu(codeTokens(tokPat)) + " with input: " + sfu(codeTokens(tok)));
    new Matches m;
    if (flexMatchIC_iterate_useTokenization
      ? match3(tokPat, tok, m)
      : match(pat, tok, m)) {
      if (flexMatchIC_iterate_debug)
        print("Got match: " + m);
      callF(onMatch, m);
    }
  }
}

Began life as a copy of #1018145