isFunctionPerformance.js

/* jshint esversion: 6*/

/* jshint ignore:start */

let TIMES = 1000 * 1000 * 100;

console.time("(() => { }) instanceof Function");
for (let i = 0; i < TIMES; i++)
    (() => {}) instanceof Function;
console.timeEnd("(() => { }) instanceof Function");

console.time("(async () => { }) instanceof Function");
for (let i = 0; i < TIMES; i++)
    (async() => {}) instanceof Function;
console.timeEnd("(async () => { }) instanceof Function");

console.time("(function () { }) instanceof Function");
for (let i = 0; i < TIMES; i++)
    (function() {}) instanceof Function
console.timeEnd("(function () { }) instanceof Function");

console.time("(async function () { }) instanceof Function");
for (let i = 0; i < TIMES; i++)
    (async function() {}) instanceof Function
console.timeEnd("(async function () { }) instanceof Function");

console.log();

console.time("typeof (() => { }) === 'function'");
for (let i = 0; i < TIMES; i++)
    typeof(() => {}) === 'function';
console.timeEnd("typeof (() => { }) === 'function'");

console.time("typeof (async () => { }) === 'function'");
for (let i = 0; i < TIMES; i++)
    typeof(async() => {}) === 'function';
console.timeEnd("typeof (async () => { }) === 'function'");

console.time("typeof (function () { }) === 'function'");
for (let i = 0; i < TIMES; i++)
    typeof(function() {}) === 'function';
console.timeEnd("typeof (function () { }) === 'function'");

console.time("typeof (async function () { }) === 'function'");
for (let i = 0; i < TIMES; i++)
    typeof(async function() {}) === 'function';
console.timeEnd("typeof (async function () { }) === 'function'");

console.log();

console.time('(() => {}).__proto__ === Function.prototype');
for (let i = 0; i < TIMES; i++)
	(() => {}).__proto__ === Function.prototype;
console.timeEnd('(() => {}).__proto__ === Function.prototype');

console.time('(async () => {}).__proto__ === Function.prototype');
for (let i = 0; i < TIMES; i++)
	(async () => {}).__proto__ === Function.prototype;
console.timeEnd('(async () => {}).__proto__ === Function.prototype');

console.time('(function() {}).__proto__ === Function.prototype');
for (let i = 0; i < TIMES; i++)
	(function() {}).__proto__ === Function.prototype;
console.timeEnd('(function() {}).__proto__ === Function.prototype');

console.time('(async function() {}).__proto__ === Function.prototype');
for (let i = 0; i < TIMES; i++)
	(async function() {}).__proto__ === Function.prototype;
console.timeEnd('(async function() {}).__proto__ === Function.prototype');

/* jshint ignore:end */