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Comment by cjs_ac | Hacker News Reader

WASM is an abbreviation for WebAssembly. If it doesn't have DOM access, WebAssembly is as related to the Web as JavaScript is to Java. A language ecosystem with no I/O capability is as much use as a one-legged man at an arse-kicking party.

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Webgl can't access the dom either

That's opengl on the web, a graphic api, you can't compare the two

I agree, but my point is that a language can be useful even if it does not have access to everything

Well, arguably the worst thing about WASM is the naming.

It's neither directly related to the web, nor is it an assembly syntax.

It's just another virtual ISA. "Direct DOM access for WASM" makes about as much sense as "direct C++ stdlib access for the x86 instruction set" - none ;)

If you want to compare the situation to x86, direct DOM access for WebAssembly is more akin to the BIOS than C++ stdlib access. If it can't interact with the outside world, it's just a very special toy that you can only use to play a game that isn't any fun, and a good candidate for those 'What's the next COBOL?' discussions that come up every now and then.

It's basically that joke about Haskell, that nobody uses it because it can't have any effect... but for WASM the developers are insisting on making sure it's real.

In German, often things are named for where they came from, like Berliner or Frankfurter. WebAssembly came from the web, so makes sense :)

Oh wow, that really is terrible naming... I always thought WASM was a specification for compiling code into something that runs natively in web browsers—like a web-specific compilation target.. Today I learned.

It's an instruction set architecture that browsers happen to support executing directly.

WASM is to webbrowsers what WebGPU is to webbrowsers. Designed with browsers in mind, but not bound to them.

Like C, which offloads IO to the standard library?

It's still there - you can still do I/O in C, even if you have to call a library function. In WebAssembly, there's no mechanism for I/O of any sort.

...in WASM you also call a function to do IO though? That function is just provided by the host environment via the function import table, but conceptually it's the exact same thing as a Linux syscall, a BIOS int-call or calling into a Windows system DLL.

As long as that function doesn't receive any parameter that is like any data actually on the DOM.

So you either create a very concrete JS library that translates specific WASM data into IO actions, or one that serializes and deserialize everything all around but can be standardized.

At this point, none of those options are much more capable than Java applets... Or, in fact, if you put a network call between the WASM and the JS, you won't even add much complexity.

> At this point, none of those options are much more capable than Java applets

Java applets allowed to load and call into native DLLs via JNI, so they were definitely much more capable than WASM, but also irresponsibly unsafe.

In your own WASM host implementation you could even implement a dlopen() and dlsym() to load and call into native DLLs, but any WASM host which cares about safety wouldn't allow that (especially web browsers).

That's not really much different from writing a language runtime for any other OS. If you're writing the Linux or Windows IO routines for say Haskell or Python or Scheme, you're writing them in C, and then you either call into them from the language's FFI or invoke platform ABI calls into the runtime from the compiled code.

But that's not the (original) argument being made. Just as IO belongs in POSIX and not C, DOM access belongs in some other standard, not WASM

There is, it is just called WASI and it specifies syscalls in a different way.

WebASM is an assembly-like dialect, after all.

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