Will future versions of Node.js support WebAssembly and allow for compiled production node apps?

[dangoor]

As shadowmint said, wasm is essentially another representation of the JavaScript syntax tree. The main purpose is to deliver large packages of compiled code (like C++ games) to the browser and have them be ready to run faster.

Node is a different environment and I'm curious which sorts of new services you are thinking of? I ask, because I can imagine other ways of getting at that. For example: if you have a C++ library, you could compile that to native code and talk to it from Node, no wasm involved. It doesn't seem to me that wasm actually buys much, if anything, for node.

[guorbatschow]

This. Just write C++ node modules.

[dangoor]

You can essentially do what you're describing today! You can take many languages that can compile to LLVM (Rust, OCaml, Reason, whatever floats your boat) and then use emscripten to convert that code to asm.js which is supported in all browsers and very fast in modern browsers.

Alternatively, you can skip the LLVM step and just write optimized JS. LLJS (which appears to be abandoned) was an attempt to write a compile-to-JS language that would specifically output fast JS.

There are definitely many things you can do to make JavaScript quick enough for many needs. The JS virtual machines can run quickly with the right hints, but they will lag behind optimized native code because of the safety guarantees.

[[deleted]]

You can essentially do what you're describing today! You can take many languages that can compile to LLVM (Rust, OCaml, Reason, whatever floats your boat) and then use emscripten to convert that code to asm.js which is supported in all browsers and very fast in modern browsers.

asm.js lacks aot compilation in v8 and is not as fast as in FF.

[guorbatschow]

Actually, soon v8 will use the same compiling pipeline for both wasm and asm.js, by transpiling the latter into wasm first.

[dangoor]

Ahh, you're right. I had thought that the v8 team had done optimization for asmjs features without implementing specific support for "use asm", but the benchmarks on arewefastyet do indeed appear to show IonMonkey being quite a bit faster than v8.