curry&unCurry函数

unCurry函数与curry函数区别：
curry化函数：固定部分参数，返回一个接受剩余参数的新函数，目的是为了缩小适用范围，创建一个针对性更强的函数。

unCurry化函数：扩大适用范围，创建一个应用范围更广的函数。使本来只有特定对象才适用的方法，扩展到更多的对象。

unCurry函数  参考：https://www.cnblogs.com/pigtail/p/3450852.html   https://juejin.im/post/5b561426518825195f499772#heading-7

方法一：
class Toast{

    constructor(){

        this.prompt=''

    }

    show(){

        console.log(this.prompt);

    }

}

var temObj={prompt:'tem'}

Toast.prototype.show.call(temObj)

function unCurry(fn){

    return function(context){

        var args=Array.prototype.slice(1)||[];

        fn.apply(context,args)

    }

}

var unCurryShow=unCurry(Toast.prototype.show);

unCurryShow(temObj)

方法2

Function.prototype.unCurrying = function(){

    var self = this;

    return function(){

        return Function.prototype.call.apply(self, arguments);

    }

    //return this.call.bind(this);

}

// 使用

var objShow = Toast.prototype.show.unCurrying();

objShow(obj);

应用：

Function.prototype.unCurry=function(){

    return this.call.bind(this)

}

var objPush=Array.prototype.push.unCurry();

var temObj={};

objPush(temObj,'a','b')

curry&unCurry函数-LMLPHP

var toUpperCase = String.prototype.toUpperCase.unCurrying();

console.log(toUpperCase('avd')); // AVD

function AryUpper(ary) {

    return ary.map(toUpperCase);

}

console.log(AryUpper(['a', 'b', 'c'])); // ["A", "B", "C"]

var call = Function.prototype.call.unCurrying();

function $(id) {

    return this.getElementById(id);

}

var demo = call($, document, 'demo');

console.log(demo);

//Function.prototype.call.call(fn,context,...args)

var objToString=Object.prototype.toString.unCurry()

var fn1=function(){}

objToString(objToString)

curry&unCurry函数-LMLPHP

curry化 参考：https://juejin.im/post/5bf9bb7ff265da616916e816

function myCurry(fn){

        if(fn.length<=1)return fn;

        let generator=function(...args){

            return (args.length === fn.length?fn(...args):function(...arg){return generator(...args,...arg)})

        };

        return generator()

    }

参考:https://juejin.im/post/5cef46226fb9a07eaf2b7516#heading-11

带占位符的curry

function curry(fn){

        let placeHolder='_';

        if(fn.length<=1)return fn

        function generator(oldArgs=[],newArgs){

            oldArgs.forEach((item,ind,arr)=>{

                if(item==placeHolder){

                    let spliceIndx=newArgs.findIndex(newArg=>newArg!==placeHolder)

                    arr[ind]=newArgs.splice(spliceIndx,1)[0]

                }

            })

            Array.prototype.push.apply(oldArgs,newArgs)

            let realArgs=oldArgs.filter(item=>item!==placeHolder);

            if(realArgs.length===fn.length){

                return fn(...realArgs)

            }else if(realArgs.length===fn.length){

                throw new Error('超出初始函数参数最大值')

            }else{

               return (...newArgs)=>{return generator(oldArgs,newArgs)}

            }

        }

        return generator()

    }

　　function arr(a,b,c,d){
　　　return [a,b,c,d]
　　}

curry&unCurry函数-LMLPHP