Function.prototype.myApply = function(context, args) {
    // Step 1: 判斷調(diào)用對(duì)象
    if (typeof this !== 'function') {
        throw new TypeError('Type Error');
    }

    // Step 2: 獲取 this
    context = context || window;

    // Step 3: 創(chuàng)建一個(gè)唯一的屬性名
    const fnSymbol = Symbol();
    context[fnSymbol] = this;

    // Step 4: 調(diào)用這個(gè)方法
    const result = args ? context[fnSymbol](...args) : context[fnSymbol]();

    // Step 5: 刪除我們新創(chuàng)建的方法
    delete context[fnSymbol];

    return result;
}

// 使用示例
function greet(greeting, punctuation) {
    return greeting + ', ' + this.name + punctuation;
}

let person = {name: 'John'};
console.log(greet.myApply(person, ['Hello', '!']));  // Output: 'Hello, John!'