'use strict' const Benchmark = require('benchmark') const suite = new Benchmark.Suite let obj = process.env suite .add('for in', function() { for(let i in obj) { let o = obj[i] } }) .add('while --', function() { let keys = Object.keys(obj) let l = keys.length while(l--) { let o = obj[keys[l]] } }) .add('while shift', function() { let keys = Object.keys(obj) let k while(k = keys.shift()) { let o = obj[k] } }) .on('cycle', function(event) { console.log(String(event.target)) }) .on('complete', function() { console.log('Fastest is ' + this.filter('fastest').map('name')) }) .run({ 'async': true })