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0 pointsvinnymac2y ago0 comments

At the moment you need to send state between WebAssembly and JS contexts in order to manipulate the DOM.

> By itself, WebAssembly cannot currently directly access the DOM; it can only call JavaScript, passing in integer and floating point primitive data types. Thus, to access any Web API, WebAssembly needs to call out to JavaScript, which then makes the Web API call. Emscripten therefore creates the HTML and JavaScript glue code needed to achieve this.

> Note: There are future plans to allow WebAssembly to call Web APIs directly.

https://developer.mozilla.org/en-US/docs/WebAssembly/Concept...

0 comments

CryZe2y ago

This is no longer true, there's various high level types that WebAssembly can pass around, such as reference types (opaque objects from the outside world, i.e. JavaScript objects) and all the new GC types. So the only thing stopping you from calling into web APIs is importing them into the WebAssembly, which atm is indeed still a manual process (or automated with some codegen).

singularity20012y ago

As you said these objects are currently opaque and still need horrible glue code to transform to/from wasm/js.

politelemon2y ago

Allowing WASM to call various Web APIs should be interesting and open up more possibilities and applications, although I can see it becoming more of a security concern as well.

The document links to a repository talking about garbage collection, but I couldn't find where they're discussing opening up to Web APIs. Any ideas anyone?

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