Storing lua functions in rust

[Randommist]

I'm trying to implement an approach where lua code is written like this

app.register("start", function (payload)
    -- some code
end)

app.register("playerConnect", function (payload)
    -- some code
end)

app.register("playerDisonnect", function (payload)
    -- some code
end)

for this I need to implement the app.register function on the rust side which will save the functions passed to it and match them by name (hashmap). that's what i'm trying to do

fn main() {
    let mut handlers: HashMap<String, mlua::Function> = HashMap::new();
    
    let lua = Lua::new();
    let app = lua.create_table().unwrap();

    let register = lua.create_function(move |lua, (name, func): (String, mlua::Function)| {
        handlers.insert(name.to_string(), func);
        Ok(())
    }).unwrap();

    app.set("register", register).unwrap();
    lua.globals().set("app", app).unwrap();

    let script = fs::read_to_string("main.lua").unwrap();
    lua.load(script);

    handlers.get("start").unwrap().call::<_, ()>(()).unwrap();
}

I get the error cannot borrow `handlers` as mutable, as it is a captured variable in a `Fn` closure cannot borrow as mutable
maybe I chose the wrong approach, can you tell me how to implement my idea

[Randommist]

the solution is to use lua.create_registry_value and lua.registry_value for more information: #290