svoid tok_numberFunctionNames(LS tok) {
  int n = l(tok);
  new L<IntRange> reToks;
  for (int i = 1; i < n-2; i += 2) {
    S number, id;
    if (isInteger(number = tok.get(i))
      && empty(tok.get(i+1))
      && isIdentifier(id = tok.get(i+2))) pcall {
    
      continue if eq(number, "0") && swicOneOf(id, "x", "b"); // skip hex/binary constants
      continue if eqic(id, "f"); // skip float constants
      
      // skip exponential floating-point constants (e.g. 1e6)
      if (swic(id, "e") && (l(id) == 1 && empty(get(tok, i+3)) && eqGet(tok, i+4, "-")
        || startsWithInteger(substring(id, 1))))
        continue;

      // skip numbers with underscores like 1_000
      if (startsWith(id, "_"))
        continue;
        
      replaceTokens_reTokLater(tok, reToks, i, i+3, camelCase(numberToEnglish(parseLong(number))) + firstToUpper(id));
    }
  }
  reTok_multi(tok, reToks);
}