Bind C++ enums declared as enum in the IDL file.

[mlogan]

Tests passed: tests/runner.py test_webidl

[mlogan]

So, it turns out that WebIDL does not allow extended attributes to be specified for enums. This means there is no obvious way to declare enums that are within namespaces or classes.

In turn, this makes me wonder if WebIDL is really a viable option for emscripten bindings in the long run. I don't want to put a lot of effort into this if it's likely to be abandoned.

It would be trivial to modify the WebIDL parser to allow extended attributes on enums, but then we're not using WebIDL, we're using EmIDL, and I don't know if you want to go down that road.

Thoughts?

[mlogan]

There is an OK solution after all:

In the stub file:

typedef MyClass::MyEnum MyClassMyEnum;
#include "glue.cpp"

In the interface file:

enum MyClassMyEnum {
  "MyClass::e_value1",
  "MyClass::e_value2"
};
interface {
  MyClassMyEnum Foo();
};

The typedef allows the generated code to compile without any scope resolution operators. The scope resolutions in the enum values just get written directly into the binding code.

It does require binding authors to add a boilerplate typedef, but at least they aren't manually assigning integer enum values in their js glue (which is horrible).

[kripken]

That looks like a reasonable approach, nice.

[kripken]

Merged, thanks!

In general, we have already had to add some attributes to WebIDL for things to work. We may need to add more over time, but hopefully will stay close enough to normal WebIDL to be able to use existing IDL files without much conversion.