Problem when change a inner field in a mutable struct

[ramon-bernardo]

The inner field value of a struct is not being changed, requiring extraction and reinsertion.

Minimal example:

pub fn main(player) {
    dbg!(player.position.x);
    player.position.x = 0;
    dbg!(player.position.x);
}

use rune::alloc::clone::TryClone;
use rune::termcolor::{ColorChoice, StandardStream};
use rune::{Any, ContextError, Diagnostics, Module, Vm};

use std::sync::Arc;

#[derive(Any, TryClone, Debug)]
pub struct Position {
    #[rune(get, set)]
    pub x: u16,
    #[rune(get, set)]
    pub y: u16,
}

#[derive(Any, Debug)]
pub struct Player {
    #[rune(get, set)]
    pub position: Position,
}

pub fn module() -> Result<Module, ContextError> {
    let mut module = Module::new();
    module.ty::<Position>()?;
    module.ty::<Player>()?;
    Ok(module)
}

fn main() -> rune::support::Result<()> {
    let mut context = rune_modules::default_context()?;
    context.install(module()?)?;

    let mut sources = rune::sources!(
        entry => {
            pub fn main(player) {
                dbg!(player.position.x);
                player.position.x = 0;
                dbg!(player.position.x);
            }
        }
    );

    let mut diagnostics = Diagnostics::new();

    let result = rune::prepare(&mut sources)
        .with_context(&context)
        .with_diagnostics(&mut diagnostics)
        .build();

    if !diagnostics.is_empty() {
        let mut writer = StandardStream::stderr(ColorChoice::Always);
        diagnostics.emit(&mut writer, &sources)?;
    }

    let mut vm = Vm::new(Arc::new(context.runtime()?), Arc::new(result?));

    let mut player = Player {
        position: Position { x: 10, y: 10 },
    };

    vm.call(["main"], (&mut player,))?;
    Ok(())
}

Output

10
10

Expected result

10
0

Note: when the field is extracted, it works.

pub fn main(player) {
    let position = player.position;
    dbg!(position.x);
    position.x = 0;
    dbg!(position.x);
    player.position = position;
    dbg!(player.position.x);
}

Ouput

10
0
0

[ramon-bernardo]

Hi @udoprog, any update?

[udoprog]

Have you tried position: Shared<Position>?

Beyond that, I'm not even sure It's a solvable problem given how Rune works.

[ramon-bernardo]

Cool, this works! Alright, that's a "problem" for the future!

Rune playground

// https://rune-rs.github.io/play/?c=c3RydWN0IFBsYXllciB7Cglwb3NpdGlvbiwKfQoKc3RydWN0IFBvc2l0aW9uIHsKCXgsCgl5LAoJegp9CgpwdWIgZm4gbWFpbigpIHsKICAgIGxldCBwbGF5ZXIgPSBQbGF5ZXIgewogICAgCXBvc2l0aW9uOiBQb3NpdGlvbiB7CiAgICAJCXg6IDEwLAogICAgCQl5OiAyMCwKICAgIAkJejogMSwKICAgIAl9CiAgICB9OwogICAgCiAgICBkYmchKHBsYXllcik7CiAgICBwbGF5ZXIucG9zaXRpb24ueCA9IDIwMDsKICAgIGRiZyEocGxheWVyKTsKfQ%3D%3D
struct Player {
  position,
}

struct Position {
  x,
  y,
  z
}

pub fn main() {
  let player = Player {
    position: Position {
      x: 10,
      y: 20,
      z: 1,
    }
  };
    
  dbg!(player);
  player.position.x = 200;
  dbg!(player);
}

[captkirk88]

Have you tried position: Shared<Position>?

Beyond that, I'm not even sure It's a solvable problem given how Rune works.

Everything is solvable. Destroy keyboard, replace keyboard, refactor, repeat.