This crate can run on wasm32 with a little modification.

[warycat]

I wrote a traveling salesman problem in rust and build it with wasm bindgen.

1. rayon::join doesn't work on wasm32, so I limit the population under 50.
2. time::get_time is unimplemented!. so I stub the time crate return value with 0.

demo https://warycat.github.io/ga_wasm/
src https://github.com/warycat/ga_wasm

Thank you for making this awesome crate.

[Bauxitedev]

I'm trying to run genevo in WASM, I've lowered my population to under 50 to avoid crashing, but there's still a crash related to the time crate:

panicked at 'time not implemented on this platform', library/std/src/sys/wasm/../unsupported/time.rs:39:9

How would I go about "stubbing the time crate return value with 0"?

---

Update: I forked genevo and changed the chrono dependency to:

[dependencies.chrono]
version = "0.4"
features = ["wasmbind"]

(as seen in chronotope/chrono#382 (comment))

Now it works!

[ravicious]

Thanks for the examples @warycat and @Bauxitedev. I was able to run the queens and the monkeys examples from v0.5.0 with the following modifications:

1. In Cargo.toml I added this to dependencies:

rand = { version = "0.7.3", features = ["wasm-bindgen"] }
chrono = { version = "0.4", features = ["wasmbind"] }

2. I reduced the population size to 40 for the queens example and 48 for the monkeys example (48 will probably work in both cases).

I used wasm-bindgen 0.2.63 and Rust 1.54 with the default wasm-pack 0.10.0 template.

Later I might check if the examples work with a bigger population after adding wasm-bindgen-rayon. The caveats page sounds rather scary and I don't need my algorithm to perform well, yet.

[haraldmaida]

Thank you all for the feedback and input. I think I finally managed to add support for wasm32 targets to genevo. Starting with version 0.7.0 there is the crate feature wasm-bindgen that enables the support wasm32. Note that I disabled rayon (and multithreading) for wasm32 targets.

I modified the great example from @warycat to test if it really works. You can check out the modified example using genevo 0.7.0 here: https://github.com/haraldmaida/ga_wasm

[ravicious]

That’s fantastic news! Thank you very much!

I think I might try to see anyway if the previous version of genevo works with rayon if you use wasm-bindgen-rayon.

[ravicious]

Ok, I tried to make 0.5.0 run with wasm-bindgen-rayon, but I ran into problems straight away:

• wasm-bindgen-rayon uses Module Workers which doesn't work in all browsers. The polyfill recommended in the readme doesn't seem to work either.
• Even if the polyfill worked or you didn't care about people using Firefox, then you'd need to make feature detection because not all browsers support WebAssembly threads.
• To make use of those threads, you need to enable cross-origin isolation policies, which AFAIK isn't possible on GitHub Pages yet (which is what I'm using for my project).

At this point I'll just upgrade to 0.7.0 instead. ;)