code: function _String_toInt(str) {
      var total = 0;
      var code0 = str.charCodeAt(0);
      var start = code0 == 0x2b /* + */ || code0 == 0x2d /* - */ ? 1 : 0;
  
      for (var i = start; i < str.length; ++i) {
        var code = str.charCodeAt(i);
        if (code < 0x30 || 0x39 < code) {
          return elm$core$Maybe$Nothing;
        }
        total = 10 * total + code - 0x30;
      }
  
      return i == start
        ? elm$core$Maybe$Nothing
        : elm$core$Maybe$Just(code0 == 0x2d ? -total : total);
    }
docs: INT CONVERSIONS