vendors/tempy.js/relaxedCheck
    var relaxedCheck = function(str) {
      if (str[0] === "!") {
        return true;
      }
      var index = 0;
      while (index < str.length) {
        if (/[*?{}()[\]]/.test(str[index])) {
          return true;
        }
        if (str[index] === "\\") {
          var open = str[index + 1];
          index += 2;
          var close = chars[open];
          if (close) {
            var n = str.indexOf(close, index);
            if (n !== -1) {
              index = n + 1;
            }
          }
          if (str[index] === "!") {
            return true;
          }
        } else {
          index++;
        }
      }
      return false;
    };