code: function checkType(type, key, value, options) {
    options = options || {};
  
    if (value != undefined) {
      if (options.isArray)
        return checkArray(type, key, value);
  
      var checker = checkType[type];
      if (checker) return checker(key, value);
  
      console.warn("Could not check " + key + ", unknown type " + type);
      //    throw TypeError("Could not check "+key+", unknown type "+type);
    } else if (options.required)
      throw SyntaxError(key + " param is required");
  
  }
docs: Checker functions