var PriceStrategy = function() { var stragtegy = { return30: function(price) { return +price + parseInt(price / 100) * 30; }, return50: function(price) { return +price + parseInt(price / 100) * 50 }, percent90: function(price) { return price * 100 * 90 / 10000; }, percent80: function(price) { return price * 100 *80 / 10000; } } return function(algorithm, price) { return stragtegy[algorithm] && stragtegy[algorithm](price) } }(); console.info(PriceStrategy('return50', 826));