Function.prototype.myBind = function(obj,...rest){
let that = this
let bound = function(...args){
let params = [...rest,...args]
that.apply(this.constructor === that ? this : obj,params)
}
bound.prototype = that.prototype
return bound
}
https://www.cnblogs.com/echolun/p/12178655.html
原文：https://www.cnblogs.com/zhenjianyu/p/13207315.html