JSFiddle - React, Tailwind, and code Playground

JavaScript

function Car() {}

Car.prototype.moveup = function() {
  console.log('up');
}
Car.prototype.movedown = function() {
  console.log('down');
}

function repeat(car, method, n) {
  for (var i = 0; i < n; i++) {
    car[method]();
  }
}

var car = new Car();
repeat(car, 'moveup', 3);