luhn-generator/update/node_modules/arrify/index.js

A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

'use strict';
module.exports = function (val) {
	if (val === null || val === undefined) {
		return [];
	}

	return Array.isArray(val) ? val : [val];
};