Hey so question - WebAssembly can't access the DOM right? What's the whole point then, avoid Javascript? If we can't just swap out all the gnarly JS garbage whole-hog, I don't see where the business value is, given that there's plenty of language-to-js libraries.
So there's a lot of other things that can be done on the client other than interacting with the DOM. In particular, applications that render intense graphics, or manage a local database could GREATLY benefit from more efficient compiled code, and this would open up possibilities that the current JS engine wouldn't be able to deliver.
That's indeed true, but I wouldn't count Go as an example of “efficient compiled code”. It's way behind of GCC or LLVM in terms of optimizations, and being ahead-of-time-compiled is a drawback, not an asset.
About llvm, there's a WIP prototype that doesn't quite work yet[0].
And about GCC, GccGo is behind in Go's version. GCC 7 only supports Go 1.8 (with caveats). Also, it had issues at some point[2] (but this is from 2014, it may have been fixed since then).
And, on a more pragmatic point of view, when talking about Go, the huge majority talks about Go compiled with the standard Go compiler. That's why you here a lot of positive feedback about compile-times for instance.
Twitch rewrote their entire video player in C++ and compiles it down to WebAssembly with Emscripten. That way the same player can be compiled to the web, as to iOS, Android, game consoles etc. That’s a huge business case when you want to create a module to support a wide variety of platforms and targets.
Webassembly uses a javascript "glue" for accessing the DOM. The point of Webassembly is not to just be an alternative to javascript; it's to have a binary web program format that runs at close to native speeds. This makes it extremely useful for porting C/C++ applications, especially games, to the browser.
It can be a lot faster and less memory-hungry than javascript. That opens up a lot of things you can't feasibly do in JS. Game engines, image decoding, even video editing. http://webassembly.org/docs/use-cases/
