wasm-bindgen | Facilitating high-level interactions

The problem is not with the RtcIceCandidate, that derefs to JsValue.

I've never used js-sys, so I may be wrong, but the problem seems to be that converting Vec into js_sys::Array must be done explicitly (maybe because it's expensive and needs one WASM→JS call per element?).

You can convert a Vec to a JsValue like this:

You declare that your function will not return anything by saying

Your current code produces an IndexSizeError because ImageData expects an array of pixel colors (4 byte per pixel, using one of the allowed pixel representations), but you are supplying a whole PNG, which for example also includes the png header, but then compresses some pixel values for memory efficency. You will need to decode your png first, for example using image-rs and then supply the pixel values only.

Here is a basic example how to do this using the image crate:

lib.rs:

When using WebInstantiate in node without more boilerplate, just like you did, I got the same result (undefined). What works seamlessly in the browser doesn't work so well in node.

But I got string exchange working when specifically building a node module with

There isn't another source that has the same authority as the specification document, for the obvious reason that if they differed which one would take precedence?

The way it's done in modern specs from the W3C and WHATWG is that the authorative spec for the IDL is embedded in the specification. The specification itself is designed to be machine readable. For instance, you'll find each IDL definitions inside an element with the class "idl". The name of the interface can be found within each block inside a dfn element with the data attribute data-dfn-type="interface". And so on.

You can convert between .wasm (binary format) and .wat (textual format) with the The WebAssembly Binary Toolkit. It is open source. Maybe it can help you to extract the needed imports programmatically.

The proper way, should be that your host environment gives you the import requirements before you initialize the instance. The Module gives you the imports. See the "Instance variables". You get that in between the module loading and the creation of the instance that itself needs these imports.

According to async_trait documentation, futures returned by async trait methods must by default be Send:

Async fns get transformed into methods that return Pin> and delegate to a private async freestanding function.

Your async fn produced a non-Send future. So the difference between your original code and the one that uses async_trait was that the original code didn't require a Send future, it was okay with non-Send ones, whereas async_trait by default expects Send futures.

To fix the issue, you need to tell async_trait not to require Send using #[async_trait(?Send)] on the trait and the impl block. In other words, replace #[async_trait] with #[async_trait(?Send)] in both the trait declaration and the implementation, and your code should compile. (Playground.)

The error tells you that no package yewtil was found in the Git repository. If you go to the repository and check its Cargo.toml file, you will indeed notice that it doesn't include a yewtil package.

I searched in the repository for yewtil, and found this pull request that refactored the project and merged yewtil into other packages: yewstack/yew#1842.

You have two options now:

1. Drop the dependency on yewtil, and use the documentation to figure out where the features have moved that you want to use.
2. Add a tag key to the dependency to pull in the latest release that included yewtil, or simply switch to the latest published version on crates.io.

If you want to get the latest features from yew, which appears to be the case given that you're pulling in the package from GitHub and not crates.io, go with option 1. You can use the documentation and the examples in the master branch to see how to use the package in its latest version.

If you only add to the hash table and never delete you could copy and leak font_data to make it static: