/** * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ const toString = Object.prototype.toString; export function is(val: unknown, type: string): boolean { return toString.call(val) === `[object ${type}]`; } export function isDef(val?: T): val is T { return typeof val !== "undefined"; } export function isUnDef(val?: T): val is T { return !isDef(val); } export function isObject(val: unknown): val is Record { return val !== null && is(val, "Object"); } export function isEmpty(val: any): val is T { if (isArray(val) || isString(val)) { return val.length === 0; } if (val instanceof Map || val instanceof Set) { return val.size === 0; } if (isObject(val)) { return Object.keys(val).length === 0; } return false; } export function isDate(val: unknown): val is Date { return is(val, "Date"); } export function isNull(val: unknown): val is null { return val === null; } export function isNullAndUnDef(val: unknown): val is null | undefined { return isUnDef(val) && isNull(val); } export function isNullOrUnDef(val: unknown): val is null | undefined { return isUnDef(val) || isNull(val); } export function isNumber(val: unknown): val is number { return is(val, "Number"); } export function isPromise(val: unknown): val is Promise { return ( is(val, "Promise") && isObject(val) && isFunction(val.then) && isFunction(val.catch) ); } export function isString(val: unknown): val is string { return is(val, "String"); } export function isFunction(val: unknown): boolean { return typeof val === "function"; } export function isBoolean(val: unknown): val is boolean { return is(val, "Boolean"); } export function isRegExp(val: unknown): val is RegExp { return is(val, "RegExp"); } export function isArray(val: any): boolean { return val && Array.isArray(val); } export function isWindow(val: unknown): val is Window { return typeof window !== "undefined" && is(val, "Window"); } export function isElement(val: unknown): val is Element { return isObject(val) && !!val.tagName; } export function isMap(val: unknown): val is Map { return is(val, "Map"); }