index.js

'use strict';
module.exports = function restParam(func, startIndex) {
    startIndex = startIndex == null ? func.length - 1 : +startIndex;
    return function() {
        var length = Math.max(arguments.length - startIndex, 0);
        var rest = new Array(length);
        for (var index = 0; index < length; index++) {
            rest[index] = arguments[index + startIndex];
        }
        switch (startIndex) {
            case 0:
                return func.call(this, rest);
            case 1:
                return func.call(this, arguments[0], rest);
        }
    };
};