@northscaler/reflector

JavaScript's reflection for mere mortals.

Overview

This module leverages the fact that in the post-ES6 world, people use the class keyword. The primary export of this module is a class called Reflector, that essentially extends JavaScript's native Reflect class, to make getting information about classes from a class-based frame of mind a little bit more intuitive. It also allows you to add a class property to Object.prototype if you like doing that sort of stuff.

TL;DR

'use strict'

const Reflector = require('@northscaler/reflector')

class Sup {
  go () { return 'sup gone' }
}

class Sub extends Sup {
  go () { return 'sub gone'}

  stop () { return 'stop' }
}

const sup = new Sup()
const sub = new Sub()

const SupClass = Reflector.getClassOf(sup)
console.log(SupClass.name) // logs Sup

const SubClass = Reflector.getClassOf(sub)
console.log(SubClass.name) // logs Sub

console.log(Reflector.getClassOf(sub) === Sub) // logs true 

console.log(Reflector.getSuperclassOf(Sub) === Sup) // logs true 

console.log(Reflector.getAllMethodDescriptors(Sub))
// logs { own: <Sub methods>, super: { own: <Sup methods>, super: { own: <Object methods> } } }

// ...and lots more, including all Reflect methods

Add class property to Object.prototype

If you like monkeying with metastuff, this library allows you to add a class property to Object.prototype. This allows you to succinctly get the class of any object.

const defineObjectPrototypeClassProperty = require('../../main/Object.prototype.class')

defineObjectPrototypeClassProperty()

class It {hello () { return 'hello' }}

const it = new It()

console.log(it.class === It) // logs true

You can also set the class of an object.

const plain = {}

plain.class = It

console.log(plain.hello()) // logs hello

See the tests in test/unit/Object.prototype.class.spec.js for more information.