实现call-apply-bind

// 手写实现 callFunction.prototype.mCall = function(context) {  const ctx = context || window  ctx.func = this  const args = Array.from(arguments).slice(1)  const res = arguments.length > 1 ? ctx.func(...args) : ctx.func()  delete ctx.func  return res}Function.prototype.mApply = function(context) {  const ctx = context || window  ctx.func = this  const res = arguments[1]? ctx.func(...arguments[1]) : ctx.func()  delete ctx.func  return res}Function.prototype.mBind = function(context) {  const ctx = JSON.parse(JSON.stringify(context)) || window  ctx.func = this  const args = Array.from(arguments).slice(1)  return function() {    const Allargs = args.concat(Array.from(arguments))    return Allargs.length>0?ctx.func(...Allargs): ctx.func;  }}const obj =  {  getName: function() {    console.log('原始。。。', this.name)  }}const nowObj = {  name: 'js'}// obj.getName.call(nowObj)obj.getName.bind(nowObj)console.log(obj)