Answer1215

摘要： Promise.myAll = function (promises) { let res, rej; const p = new Promise((resolve, reject) => { res = resolve; rej = reject; }); let i = 0; let resul 阅读全文

摘要： Function.apply.myCall = function (ctx, ...args) { ctx = ctx null || ctx undefined ? globalThis : Object(ctx); const fn = this; const key = Sybmol("fn" 阅读全文

摘要： For Javascript Object, you cannot assume the order of Object property the same as the order of adding those property. The actual order follow this rul 阅读全文

摘要： Proxy The Proxy object enables you to create a proxy for another object, which can intercept and redefine fundamental operations for that object. So w 阅读全文

摘要： [] + [] Answer: "" Both arrays ([]) are first converted to their string representations before the + operator is applied. In JavaScript, arrays are co 阅读全文

摘要： const obj = { a: 1, b: 2, c: { d: 1, e: 2, }, }; function isObject(val) { return val !== null && typeof val "object"; } function observe(obj) { const 阅读全文

摘要： const obj = { a: 1, b: 2, c: { a: 1, b: 2, }, }; function isObject(val) { return val !== null && typeof val "object"; } function observe(obj) { for (l 阅读全文

摘要： As we know we can read property value from an object as so: const obj = {} obj.xxxx; obj[xxxx]; So what's the difference between those two? obj.x ECMA 阅读全文

摘要： Function.prototype.myBind = function (ctx, ...args) { const fn = this; return function (...subArgs) { console.log(new.target); const allArgs = [...arg 阅读全文

摘要： The new.target meta-property lets you detect whether a function or constructor was called using the new operator. In constructors and functions invoke 阅读全文