performance comparison of creating bound functions

perf-bind-vs-arrow.js

const assert = require('assert')
console.log('NODE:', process.version)
console.log('V8:', process.versions.v8, '\n--------------')

class Bind {
  constructor () {
    this.value = 1000
    this.update = this.__update.bind(this)
  }
  __update () {
    this.value++
  }
}

class Arrow {
  constructor () {
    this.value = 1000
    this.update = () => this.__update()
  }
  __update () {
    this.value++
  }
}

function test (source) {
  assert.strictEqual(source.value, 1000)
  source.update.call(null)
  assert.strictEqual(source.value, 1001)
}
function perf (func) {
  const start = Date.now()
  for (var i = 0; i < 10000000; ++i) {
    func()
  }
  return Date.now() - start
}
function perfCtor (name, Ctor) {
  const c = new Ctor()
  const update = c.update
  console.log(`${name}():new`, perf(function newTester () {
    const update = new Ctor().update
    update()
  }))
  console.log(`${name}:`, perf(function tester () {
    update()
  }))
}

test(new Bind())
test(new Arrow())

perfCtor('Arrow', Arrow)
perfCtor('Bind', Bind)


/* results
➜  temp node Javascript.js
NODE: v6.8.1
V8: 5.1.281.84
--------------
Arrow():new 3234
Arrow: 69
Bind():new 3211
Bind: 131
➜  temp nvm use 7
Now using node v7.0.0 (npm v3.10.8)
➜  temp node Javascript.js
NODE: v7.0.0
V8: 5.4.500.36
--------------
Arrow():new 3577
Arrow: 69
Bind():new 683
Bind: 138
*/

Issue filed here.
https://t.co/Dgmu1HEQgQ