static boolean jreplace_singlePosition(L<S> tok, int i, S in, S out) {
  L<S> tokin = javaTok(in);
  jfind_preprocess(tokin);
  S[] toks = toStringArray(codeTokensOnly(tokin));

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

static bool jreplace_debug;

Began life as a copy of #1002133