d at domenic.me (2015-04-19T23:38:03.507Z)
On 4/10/15, Axel Rauschmayer <axel at rauschma.de> wrote:
> The reason why you need to call the super-constructor from a derived class
> constructor is due to where ES6 allocates instances - they are allocated
> by/in the base class (this is necessary so that constructors can be
> subclassed that have exotic instances, e.g. `Array`):
>
Can you please explain how extending Array works. Also what is the
optional identifier optional for in ClassExpression:
```js
var myArray = (new class B extends Array {
constructor() {
super(1,2,3,4,5);
}
});
alert(myArray.length); // it's 0 in Babel.
```
On 4/10/15, Axel Rauschmayer <axel at rauschma.de> wrote: > The reason why you need to call the super-constructor from a derived class > constructor is due to where ES6 allocates instances - they are allocated > by/in the base class (this is necessary so that constructors can be > subclassed that have exotic instances, e.g. `Array`): > Can you please explain how extending Array works. Also what is the optional identifier optional for in ClassExpression: var myArray = (new class B extends Array { constructor() { super(1,2,3,4,5); } }); alert(myArray.length); // it's 0 in Babel. -- Garrett @xkit ChordCycles.com garretts.github.io personx.tumblr.com