// f : func(S) -> S
sS javaTokWithBrackets_recursiveTransform(fO f, S s) {
  ret join(mapCodeTokens(javaTokWithBrackets(s), func(S t) -> S {
    S t = (S) callF(f, t);
    if (!isCurlyBraced(t)) ret t;
    ret optCurly(javaTokWithBrackets_recursiveTransform(f, uncurly(t)));
  }));
}