// out: func(L<S> tok, int cIndex) -> S
// condition: func(L<S> tok, int nIndex) -> S  [yeah it's inconsistent]
static S jreplace_dyn(S s, S in, O out) {
  ret jreplace_dyn(s, in, out, null);
}

sS jreplace_dyn(S s, S in, O out, O condition) {
  L<S> tok = javaTok(s);
  jreplace_dyn(tok, in, out, condition);
  ret join(tok);
}

// leaves tok properly tokenized
// returns true iff anything was replaced
sbool jreplace_dyn(LS tok, S in, O out) {
  ret jreplace_dyn(tok, in, out, false, true, null);
}

sbool jreplace_dyn(LS tok, S in, IF0<S> out) {
  ret jreplace_dyn(tok, in, if0ToIF2(out));
}

sbool jreplace_dyn(LS tok, S in, ITokCondition cond, IF0<S> out) {
  ret jreplace_dyn(tok, in, cond, if0ToIF2(out));
}

sbool jreplace_dyn(LS tok, S in, IF1<Int, S> out) {
  ret jreplace_dyn(tok, in, (_tok, cIdx) -> out.get(cIdx));
}

sbool jreplace_dyn(LS tok, S in, IF2<LS, Int, S> out) {
  ret jreplace_dyn(tok, in, (O) out);
}

sbool jreplace_dyn(LS tok, S in, IF2<LS, Int, S> out, IF2<LS, Int, Bool> condition) {
  ret jreplace_dyn(tok, in, (O) out, (O) condition);
}

static boolean jreplace_dyn(L<S> tok, S in, O out, O condition) {
  ret jreplace_dyn(tok, in, out, false, true, condition);
}

static boolean jreplace_dyn(L<S> tok, S in, O out, boolean ignoreCase, boolean reTok, O condition) {
  L<S> tokin = javaTok(in);
  jfind_preprocess(tokin);
  
  S[] toks = toStringArray(codeTokensOnly(tokin));

  boolean anyChange = false;
  for (int n = 0; n < 10000; n++) {
    int i = findCodeTokens(tok, 1, ignoreCase, toks, condition);
    if (i < 0)
      ret anyChange;
    S expansion = cast callF(out, tok, i);
    int end = i+l(tokin)-2;
    clearAllTokens(tok, i, end); // C to C
    tok.set(i, unnull(expansion));
    if (reTok) // would this ever be false??
      reTok(tok, i, end);
    anyChange = true;
  }
  throw fail("woot? 10000! " + quote(in) + " => " + quote(out));
}

Began life as a copy of #1002133