Does it handle defining functions? I can’t get them to work.
I'm afraid it cannot, since those functions would need to be compiled into WASM first, and that's something the browser can't do.
What I could add, though, is a bunch of "standard" functions (like the ones found in Hugo, for example).
Noted!
If you already have Go libraries compiling to wasm working then you could just embed a Go interpreter like yaegi [0].