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Comment by flyinRyan | Hacker News Reader

But all of these just compile to Javascript in the end, right? I long for the day where we just have a "Browser VM" that we can all compile to instead of compiling to a high level language.

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Here's an article by the Dart team that describes why the JavaScript VM (or the Dart VM) may already be the "Browser VM" you're looking for: http://www.dartlang.org/articles/why-not-bytecode/

All of their justifications seem to have a language specific VM like the JVM in mind. If you made a strategy of a "platformless x86" approach you might be able to overcome a lot of this stuff.

You might be interest in Portable NaCL (aka PNaCL). http://www.chromium.org/nativeclient/pnacl

A VM is still a specific language, it just has a binary syntax. All VM's make tradeoffs which means they are a better fit for some languages than others. The fully language neutral VM does not exist. Given that, we might as well consider JavaScript a VM which just happen to have a text-based rater than binary source.

A VM is therefore not necessarily an improvement on JavaScript - it has to be a better VM than JavaScript, and nobody have designed that yet.

Honest question - what can you do with bytecode that you can't do with javascript? Modern javascript is fast and ubiquitous and is clearly not going away anytime soon. Isn't the human readable nature of javascript more suitable for debugging anyway?

Some features typical of VM languages, like "goto" makes it more appropriate as a compilation target, because lots of higher-level control structures kan be compiled to gotos. Of course goto could also be added to the JavaScript language as is, but then we have a conflict since goto is nice in a low-level language, but discouraged in higher level languages. This conflict of interest in language design does not exist when the user language is seperate from the VM-language.

I agree with your point though.

The Relooper is good enough that the lack of goto isn't an issue in a practical sense these days.

The Emscripten Relooper algorithm "takes basic blocks of code - chunks of simple code, at the end of which are branches to other blocks of code - and generates high-level structure from that using loops and ifs."

http://mozakai.blogspot.com/2012/05/reloop-all-blocks.html

That's my point. The Relooper does a good job with vast majority of code that you might conceivably want to compile to JS, making the lack of goto not a problem in a practical sense for these compilers.

Hah, sorry, I didn't know what Relooper did, so I posted a comment describing where to find out about it for other people.

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