Provide js_namespace argument on static declarations

[pepsighan]

When accessing static attributes of a js api, we are only allowed to use it the following way.

type window;
static window: window;
type Document;

#[wasm_bindgen(method, getter, structural)]
fn document(this: &window) -> Document;

But to create a cleaner api allowing something like window::document would require js_namespace argument be allowed on static declarations.

type window;
type Document;

#[wasm_bindgen(js_namespace = window)]
static document: Document;

[alexcrichton]

Hm so it looks like js_namespace works today? Are you thinking that the generated code should generate a module called window though?

[pepsighan]

@alexcrichton No, putting js_namespace on static does not work.

For the second question, yeah, I would love if a module was created.
Why? Its comes down to the choice of syntax. window.document() vs window::document.
Also, you told me using structural creates a shim, I think using js_namespace would directly retrieve the value.

[alexcrichton]

Hm can you gist a full example of what isn't working for you? The simple examples I tried locally all seemed to work :(

[pepsighan]

I am using version 0.2.8.

#[wasm_bindgen]
extern {
    pub type window;
    pub type Document;

    #[wasm_bindgen(js_namespace = window)]
    static document: Document;
}

Compiler error:

error: expected one of `const`, `crate`, `default`, `extern`, `fn`, `pub`, `type`, or `unsafe`, found `static`
 --> src/lib.rs:8:1
  |
8 | #[wasm_bindgen]
  | ^^^^^^^^^^^^^^^ expected one of 8 possible tokens here

error: expected one of `const`, `crate`, `default`, `extern`, `fn`, `pub`, `type`, `unsafe`, or `}`, found `;`
 --> src/lib.rs:8:1
  |
8 | #[wasm_bindgen]
  | ^^^^^^^^^^^^^^^ expected one of 9 possible tokens here

[alexcrichton]

Aha, there we go!