Update WebIDL definition in WebGL 2.0 to use new mixin syntax

[tobie]

Hi all!

WebIDL recently introduced dedicated syntax for mixins.

This syntax replaces the [NoInterfaceObject] extended attribute and implements statement which have been deprecated (except for a few legacy uses cases explicitely mentioned in the spec).

You can read more about it here.

In most cases, the changes should be relatively straightforward. The now deprecated:

interface Foo { };

[NoInterfaceObject]  // (Mostly) DEPRECATED
interface Bar { };
Foo implementes Bar; // DEPRECATED

should just be rewritten as:

interface Foo { };

interface mixin Bar { };
Foo includes Bar;

Additonaly, a section on when to use partials and mixins has been added to the spec. It's short and might be worth a read.

It seems the following interface in WebGL 2.0 is impacted by this change:

• WebGL2RenderingContextBase

The suggested syntax change would be as follows:

interface mixin WebGL2RenderingContextBase {
  /* ... */
};

interface WebGL2RenderingContext { };
WebGL2RenderingContext includes WebGLRenderingContextBase;
WebGL2RenderingContext includes WebGL2RenderingContextBase;

We're sorry for the inconvenience this causes, but our hope is that this ultimately makes things simpler and clearer for everybody.

As always, please feel free to reach out if you have any questions.

Thanks!

---

Tracked in: whatwg/webidl#472 | Original pull-request: whatwg/webidl#433

[bzbarsky]

@kenrussell the new IDL isn't valid because it has a mixin including another mixin, no?

[kenrussell]

@bzbarsky where do you see that?

WebGLRenderingContext and WebGL2RenderingContext are the two concrete interfaces, each of which includes multiple mixins. Those mixins don't include other ones.

If you see some problem please file a new issue referencing this one or, better, put up a pull request with a suggested fix. Thanks.

[bzbarsky]

@kenrussell I was looking at the changes made in #2566, which is what closed this issue.

It looks like since then the problem has been fixed in #2575