Refactor code in src/01-intro/07-modern.js to use arrow functions, spread operator, rest operator, and exponentiation operator

Author: loiane

src/01-intro/07-modern.js

@@ -0,0 +1,41 @@
+// Path: src/01-intro/07-modern.js
+
+/* Arrow function example */
+const circleAreaFn = function circleArea(radius) {  
+  const PI = 3.14;  
+  const area = PI * radius * radius;  
+  return area;  
+};
+console.log(circleAreaFn(2)); // 12.56
+
+// refactoring to use arrow function
+const circleArea = (radius) => {  // {1}
+  const PI = 3.14;  
+  return PI * radius * radius;  
+};
+
+// simplified version
+const circleAreaSimp = radius => 3.14 * radius * radius;
+console.log(circleAreaSimp(2)); // 12.56
+
+// no parameters
+const hello = () => console.log('hello!');
+hello(); // hello!
+
+/* Spread operator example */
+const sum = (x, y, z) => x + y + z;  
+
+const numbers = [1, 2, 3];
+console.log(sum(...numbers)); // 6
+
+/* Rest operator example */
+const restParamaterFunction = (x, y, ...a) => (x + y) * a.length;
+console.log(restParamaterFunction(1, 2, 'hello', true, 7)); // 9
+
+/* Exponentiation operator example */
+const r = 2;
+let area = 3.14 * r * r;  
+area = 3.14 * Math.pow(r, 2);
+area = 3.14 * r ** 2;
+
+// to see the output of this file use the command: node src/01-intro/07-modern.js