stdweb

Yes. For a while, you've been able to embed JavaScript wrappers using stdweb (https://github.com/koute/stdweb). There are pre-built libraries covering much of the DOM. But you may need to submit PRs if you get heavily into <video> or something else with non-standard APIs. The shiny new toy is wasm-bindgen (https://github.com/rustwasm/wasm-bindgen), which will soon allow the use of WebIDL (https://heycam.github.io/webidl/) to wrap the entire browser API, if I understand correctly. In practice, it all seems to work pretty well. But for public-facing sites, you need to watch the number of dependencies you include and keep the *.wasm size down.

How it compares to stdweb (https://github.com/koute/stdweb) ?

In practice, most WASM languages are going to want good interop with JavaScript, so if nothing else is done, I expect that would become the standard for foreign functions, much like C FFI is on the desktop. For example, look at what Rust is doing [1]. For a new language targeting WASM, it might be nice to use JavaScript strings directly, without needing to convert them at the border? JavaScript strings aren't perfect (I prefer how Go does it) but they're usually good enough. [1] https://github.com/koute/stdweb

To add a specific example here, I've recently compiled a roguelike I'm working on to WASM, not knowing what to expect when I started. This required only a handful of changes across the codebase (mostly handling external resources such as the filesystem and the random generator) and then implementing a bit of JavaScript that took the drawcalls from the WASM core and rendered them on the canvas. And vice-versa, a bit of JS that passed the browser input into the WASM game. Since the original game had no concept of a DOM, it didn't matter to it. I think WASM can be huge for browser games. But like Steve said, you can call any JavaScript function and manipulate the DOM that way. At least for Rust, there's also a library that does this for you. So you can have Rust code that uses a DOM API and the WASM <-> JS bridge is handled for you: https://

Its an optional dependency. You can build without it by just using a nightly version of rust with the wasm32-unknown-unknown backend. An example of using cargo-web with the stdweb rust project: https://github.com/koute/stdweb#running-the-examples

> the tooling for using emscripten with rust is superior emscripten is no longer required for Rust to target WASM. There is a new target of wasm32-unknown-unknown. This project gives you quick bootstrap instructions into WASM with Rust: https://github.com/koute/stdweb Very quick to get started with, and the examples get you going quickly. I just used it yesterday (nothing fancy), and everything worked right out of the box.

Rust -- https://github.com/koute/stdweb C++ -- https://github.com/mbasso/asm-dom I don't know exactly how these work but Emscripten allows interop both ways (embedding JS in native code and calling native code from JS) -- https://kripken.github.io/emscripten-site/docs/porting/conne...

Compiling Rust to WebAssembly and building https://github.com/koute/stdweb Rust is a powerful enough language where you can do crazy stuff like write inline JavaScript inside of your Rust code, and freely pass data in and out of those JS snippets, and compile the whole thing to WebAssembly.

It can through a thin bridge. See https://github.com/koute/stdweb

Javascript also does not have access to the chrome of the browser. Unless it's running in a WebExtension context, in which case you can also run WASM there. WASM can CALL INTO JAVASCRIPT CODE. Which means it can do anything JS can do — in a "clunky hack" kind of way, sure, but people are building sugar on top of this already: https://github.com/koute/stdweb So it's not the kind of sandbox you're thinking about. It's literally the same sandbox as JavaScript itself. Also, I just realized — you're probably thinking of "compiling to JS" as in TypeScript/BuckleScript/Elm/ghcjs/ScalaJS/… — and yeah, that isn't easy to replace, because you'd have to implement a whole garbage collected runtime for WASM currently and that's kinda ridiculous. Others (including me) are thinking of "compiling" as in Emscripten, and WASM was literally created to optim

https://github.com/koute/stdweb There's a todomvc example app written in rust with no javascript besides the loader.

> but anything that makes it easier to pass and convert/cast object/arguments to and from javascript would be welcome. Perhaps this crate would be of some use to you? https://github.com/koute/stdweb