Circle.js

/**
 * This class represents a circle and can calculate it's perimeter and area
 * https://en.wikipedia.org/wiki/Circle
 * @constructor
 * @param {number} radius - The radius of the circle.
 */
export default class Circle {
 constructor(radius) {
 this.radius = radius
 }

 perimeter = () => {
 return this.radius * 2 * Math.PI
 }

 area = () => {
 return Math.pow(this.radius, 2) * Math.PI
 }
}