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Mobile Safari may support WASM, but I think the GP is suggesting that a native iOS app would not be permitted to load, compile, and execute a WebAssembly module.

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I might be wrong, but I think that one should be able to utilize JavaScript engine within native iOS app which will use fast implementation.

JavaScriptCore and JS running in a web page using WKWebView are both running in the same app process and do not support WASM since they cannot generate code (cannot write to executable memory pages).

SFSafariViewController does support WASM by executing in a separate more privileged process but interaction with the app is very limited.

WKWebView does as well because it too runs out-of-process. You can load WebAssembly into it.

But WKWebView is equivalent to running inside a browser, with no system access.

If JSCore allowed WASM JIT-ing, one could easily port WASI to iOS for full system access, and update iOS apps by downloading new wasm versions. Of course Apple won't do that citing __Insert__App__Store__excuse__here, but everyone knows it's because they want that sweet 30% cut, and that can only be effectively enforced with a tight chokehold on updates

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