SOURCE

var fn = function (a, b, c) {
    //console.log(a, b, c)
    return a + b + c
};
function curryIt(fn) {
    var k = []
    var kk = fn
    return function a(arg1) {
        //console.log(...arguments)
        for (let i = 0; i < arguments.length; i++) {
            k.push(arguments[i])
        }
        //console.log(k)
        return function b(arg1) {
            //console.log(...arguments)
            for (let i = 0; i < arguments.length; i++) {
                k.push(arguments[i])
            }
            //console.log(k)
            return function c(arg1) {
                for (let i = 0; i < arguments.length; i++) {
                    k.push(arguments[i])
                }
                //console.log(k)
                return fn(...k)
            }
        }
    }
}
console.log(curryIt(fn)(1)(2)(3));
//console.log(curryIt().length)