Water Off a Duck's Back

Description:

Allows for easy error handling in bevy.

Warning: Darkness

This crate requires nightly, as it uses try_trait_v2 to convert from results and options to () using the ? operator.
It also uses try_as_dyn in order to prefer Display to Debug implementations when displaying an error.
I have little doubt that eventually in some form these features will be stabilised.

Example:

use bevy::{log::LogPlugin, prelude::*};
use duck_back::Else;

fn main() {
    App::new()
        .add_plugins(DefaultPlugins.set(LogPlugin {
            filter: "duck_back=trace".to_string(),
            ..default()
        }))
        .add_systems(Startup, (start, query))
        .run();
}

fn start() {
    let bad: Option<u32> = None;
    let _bad: u32 = bad.else_return()?;
}

fn query(transform: Query<&Transform>) {
    let _transform: &Transform = transform.single().else_error()?;
}

2026-02-16T05:05:12.958909Z ERROR duck_back: (examples/messages.rs:20:5)
Failed to unwrap value.
No entities fit the query bevy_ecs::system::query::Query<'_, '_, &bevy_transform::components::transform::Transform>
2026-02-16T05:05:12.958934Z TRACE duck_back: (examples/messages.rs:16:5)
Failed to unwrap value.