Javascript universal random function (ES6+ !!!)

__randomN.js

function __randomN(...args) {
	if (Array.isArray(args[0])) return __randomN(args[0]);

	function getRandomIntMax(max) {
		return Math.floor(Math.random() * Math.floor(max));
	}

	function getRandomIntInclusive(min, max) {
		min = Math.ceil(min);
		max = Math.floor(max);
		return Math.floor(Math.random() * (max - min + 1)) + min; //The maximum is inclusive and the minimum is inclusive
	}

	switch (args.length) {
		case 0:
			return Math.random();
		case 1:
			return getRandomIntMax(args[0]);
		default:
			return getRandomIntInclusive(args[0], args[1]);
	}
}