Different ways to write functions

function.js

function A(){};             // function declaration
var B = function(){};       // function expression
var C = (function(){});     // function expression with grouping operators
var D = function foo(){};   // named function expression
var E = (function(){        // IIFE that returns a function
  return function(){}
})();
var F = new Function();     // Function constructor
var G = new function(){};   // special case: object constructor
var H = x => x * 2;         // ES6 arrow function