1/* 2 * Copyright (c) 2021 Huawei Device Co., Ltd. 3 * Licensed under the Apache License, Version 2.0 (the "License"); 4 * you may not use this file except in compliance with the License. 5 * You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software 10 * distributed under the License is distributed on an "AS IS" BASIS, 11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 * See the License for the specific language governing permissions and 13 * limitations under the License. 14 */ 15 16const is = (type) => { 17 return (source) => Object.prototype.toString.call(source) === `[object ${type}]`; 18}; 19 20exports.isFunction = is('Function'); 21exports.isUndefined = is('Undefined'); 22exports.isObject = is('Object'); 23exports.isArray = is('Array'); 24exports.isNull = is('Null'); 25