How to call a Rust function from JanetClient?

[Andriamanitra]

My goal is to embed Janet into a Rust program as a sort of plugin language, so I need a way to both interpret Janet scripts from Rust and to call Rust functions from those Janet scripts.

I'm following the example of declaring a Janet module, but I can't figure out how to call Rust functions from JanetClient. Here's what I have so far:

use janetrs::{client::JanetClient, declare_janet_mod, janet_fn, Janet};

#[janet_fn(arity(fix(0)))]
fn rust_hello(args: &mut [Janet]) -> Janet {
    println!("Hello world!");
    Janet::nil()
}

declare_janet_mod!("rust";
    {"hello", rust_hello},
);

fn main() {
    let janet = JanetClient::init_with_default_env().unwrap();
    let result = janet.run("(rust/hello)");
    println!("{:?}", result);
}

This just gets me a CompileError (I think the declared "rust" module is not available to the JanetClient, but I don't know how to fix it)

main:1:1: compile error: unknown symbol rust/hello
Err(CompileError)

[Andriamanitra]

Nevermind I figured it out – turns out you don't need to use declare_janet_mod! at all:

use janetrs::{client::JanetClient, env::CFunOptions, janet_fn, Janet};

#[janet_fn(arity(fix(0)))]
fn rust_hello(args: &mut [Janet]) -> Janet {
    println!("Hello world!");
    Janet::nil()
}

fn main() {
    let mut janet = JanetClient::init_with_default_env().unwrap();
    janet.add_c_fn(CFunOptions::new(c"rust/hello", rust_hello));
    let result = janet.run("(rust/hello)");
    println!("{:?}", result);
}