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I think you're confusing this new Chrome-only thing with ES6 classes that just saves you from using a library to create constructor/prototype objects. In ES6 "class" is just a keyword that makes it easy to contruct objects that are very typical in day-to-day JS. Inheritance is already a thing that happens.

I'm not. See above, "class free object oriented programming". You don't need prototypical inheritance to have inheritance in JavaScript. Crockford gives examples. You don't need the "class" keyword. All it's going to do is steer people in the wrong direction.

Can you give an example of inheritance without prototypes in javascript?

from D.C.

    function base(spec) {
        var that = {},
            member,
            method = function() {
                // spec, member, method
            };
        that.method = method;
        return that;
    }

    function derived(spec) {
        var that = base(spec),
            member,
            method = function() {
                // spec, member, method
            };
        that.method = method;
        return that;
    }

I'd suggest you watch the talk linked above for this stuff in context.

That is not inheritance. `instanceof` doesn't work. There would be no way to know that an object from derive dis of the type of base.

That's also very memory inefficient. The method function gets made for every instance. With prototypes there would be only 1 function in memory. This stuff matters at scale.

Watch the talk.

You've got a gig of ram in your pocket. Memory doesn't matter for 99.99999% of apps. The memory taken by your objects isn't where your memory goes. It goes to images and other big stuff. A few extra bytes per object isn't going to kill you. Optimize for programmer time not memory, especially not in memory on things that don't matter.

Why are you using "instanceof". The whole point of inheritance is you shouldn't have to ask. If you are asking your doing it wrong

and then how do you implement super with your system? because that's the point of prototypes,the fact that you're not overloading methods but you have access to the prototype chain.much harder to do with your method.

You shouldn't need access to the prototype chain. Accessing that chain is an anti-pattern.

no it isn't,that's how you implement "super" in javascript.

Check out Daniel X. Moore's `{SUPER: SYSTEM}`. http://stackoverflow.com/a/3731253

> That we don't actually need all the structure to get shit done is what people are finally coming to realize.

Getting stuff done until the code base grows and others have to adapt or build up on the code you've written : the idea of bringing in structure is to encode knowledge about the problem you are solving and keeps it all maintainable (admitted, if done right).

> In C++ (and similar classical languages) in order to be able to pass in different implementations of a class you need to create a base class or interface.

And that is a good thing IMHO, see above. However I agree that, particularly in C++, an interface definition is very verbose. Unfortunately it has no pure Interface concept.

You can always use pure virtual classes, but requires discipline and virtual inheritance.

As a javascript programmer, I have perceived es6 "classes" as nothing but syntactic sugar. They should just construct the equivalent constructor+prototype combo. You can still create anonymous objects quickly, and use any object as prototype for another.

> As a javascript programmer, I have perceived es6 "classes" as nothing but syntactic sugar.

That's basically what they are.

> You can still create anonymous objects quickly, and use any object as prototype for another.

Hell you can create anonymous objects even faster with ES6 since object literals also get the short method notation and computed properties.

Yes, but let's admit it, the presence of classes will inevitably lead to their ever-presence, if only for the fact that they are what most people coming from other languages are used to.

The absence of class already leads to their ever presence, each project simply reimplements its own instead of using the built-in syntactic sugar. The class sugar is simply a way for the creation of (prototype + constructor) pairs not to be a pain in the ass, nothing more and nothing less.

> As someone who's coded C since the 80s and C++ since the 90s I find JavaScript massively freeing.

I've gone back and forth between dynamic and static and strict and loose in every combination and I don't find the dynamic/loose to be particularly freeing anymore. The problem is you can't really rely on anything. It doesn't so much as solve the problem that Crockford is talking about, it just moves it somewhere else. You don't have to refactor but you're going to end up with two (or more) different things that exist at the same time instead of one.

> Look at the mocking libraries for JavaScript. They're sooooooooo much easier to write than anything for classical languages because it's so easy to do in JavaScript.

This is a great point and it's a perfect example of the advantages and the horrors of the JavaScript model. A mock is supposed to be an object that does something completely different (typically nothing) but otherwise looks and functions like the real thing. Maybe just in one slight exceptional way. JavaScript makes this easy. But it also makes it easy to make those same changes outside of mocking and tests and that is just debugging hell waiting to happen.

You can write bad spaghetti code in any language. You avoid that with style guides, linters, and code review.

I don't see how strict typing couldn't fit at the end of your list as well.

It could but some of us have had the experience of massive productive increases in JavaScript over our decades of experience in statically typed languages.

And note I'm specifically calling out JavaScript. Other dynamic languages IMO haven't provided the same benefits because they're still following old models.

When you truly grok JavaScript and stop trying to use it like your other languages it really starts to shine. It's not perfect but it is different.

> And it's true. Look at the mocking libraries for JavaScript. They're sooooooooo much easier to write than anything for classical languages because it's so easy to do in JavaScript. In my own experience I have a mutli-user networking system written in JavaScript and a library in C#. To reimplement the same things in JavaScript in C# is a huge amount of code bloat. I have to make classes and meta classes and all kinds of other indirection just so I can make an Event system that is generic. In JavaScript that's 2 or 3 lines

That does not follow from what you quoted, and what you quoted is a non-sequitur to start with.

What you're raving about can be achieved just as easily in any dynamically typed language. Hell you probably get 80~90% of that in a structurally typed language (OCaml objects, Go).

> In JavaScript you can build objects on the fly.

Which you can do in many other languages, including statically typed ones. Here's an object in Ocaml:

    # let s = object
        val mutable v = [0; 2]

        method pop =
          match v with
          | hd :: tl -> 
            v <- tl;
            Some hd
          | [] -> None

        method push hd = 
          v <- hd :: v
      end

And that's statically typed.

> The problem with 'class' in ES6 is that it will prevent people from learning this new, easier, faster, simpler way of working because instead they just bring the classical baggage to JavaScript.

That's patent nonsense, not to mention ES6's class shortcuts apply to object literals as well, the only thing the class statement does is remove the bullshit and mostly useless boilerplate Javascript demands when creating a reusable prototype due to it being a garbage language, and its "prototypal" object system being there not because it's good and going to save the masses but because it was the easiest way to have an object system working in a week. It's just a sad and pitiful shadow of Self's object system from which it draws so little you have to know the relation's there to find it.

" They're sooooooooo much easier to write than anything for classical languages because it's so easy to do in JavaScript."

You can do that in a language with classes and even one with optional types e.g. you can use jasmine perfectly well to mock typescript objects (because they are just JavaScript dynamic objects)

" I have to make classes and meta classes and all kinds of other indirection just so I can make an Event system that is generic."

I remember reading Gilad Bracha saying somewhere that enabling exactly this kind of system was exactly one of the use cases for Dart which is class based with optional types. You can have your cake and eat it too!