CoffeeScript: Using instanceof vs Class.constructor.name

Question

If I have a class:

class Haha
  constructor: (@lolAmount = 1) ->
    alert @lolAmount

And I want to check if an object is of the right c

Answer 1

First of all, constructor is also straight JavaScript:

Returns a reference to the Object function that created the instance's prototype.

So when you say o.constructor, you're really doing straight JavaScript, the name constructor for the CoffeeScript object initialization function is a separate matter.

So now you have a choice between using JavaScript's constructor property or JavaScript's instanceof operator. The constructor just tells you what "class" was used to create the object, instanceof on the other hand:

[...] tests whether an object has in its prototype chain the prototype property of a constructor.

So instanceof is the right choice if you want to allow for subclassing.