重构call apply bind方法

以下是重构call、apply、bind方法的示例：

1. 重构call方法：

Function.prototype.myCall = function(context, ...args) {
  context = context || window;
  const fn = Symbol();
  context[fn] = this;
  const result = context[fn](...args);
  delete context[fn];
  return result;
};

// 示例
function greet(name) {
  console.log(`Hello, ${name}!`);
}

const person = {
  name: 'Alice'
};

greet.myCall(person, 'Bob'); // 输出：Hello, Bob!

2. 重构apply方法：

Function.prototype.myApply = function(context, args) {
  context = context || window;
  const fn = Symbol();
  context[fn] = this;
  const result = context[fn](...args);
  delete context[fn];
  return result;
};

// 示例
function greet(name) {
  console.log(`Hello, ${name}!`);
}

const person = {
  name: 'Alice'
};

greet.myApply(person, ['Bob']); // 输出：Hello, Bob!

3. 重构bind方法：

Function.prototype.myBind = function(context, ...args) {
  const fn = this;
  return function(...innerArgs) {
    return fn.apply(context, [...args, ...innerArgs]);
  };
};

// 示例
function greet(name) {
  console.log(`Hello, ${name}!`);
}

const person = {
  name: 'Alice'
};

const greetPerson = greet.myBind(person);
greetPerson('Bob'); // 输出：Hello, Bob!