手写函数柯里化原理

函数柯里化原理：

const getSum = (args) => {          //参数求和方法
    return args.reduce((a, b) => {
        return a + b;
    })
}
const foo = (...args) => {
    const totalParamsSum = getSum(args);            //首次调用，第一个参数，并作为总和total
    const fn = (...arg2) => {
        const sum2 = getSum(arg2);
        return foo(totalParamsSum + sum2);       
    }
    fn.toString = () => {           
        return totalParamsSum;
    }
    return fn;			//只有接下来还有参数进行调用，就会再次执行fn，累加totalParamsSum
}
console.log(foo(1)(2)(3) == 6)

记录一下~