bevy_mod_reaction 0.1.0

Reactive components for Bevy
Documentation 
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# bevy_mod_reaction


[![License](https://img.shields.io/badge/license-MIT%2FApache-blue.svg)](https://github.com/matthunz/bevy_mod_reaction)
[![Crates.io](https://img.shields.io/crates/v/bevy_mod_reaction.svg)](https://crates.io/crates/bevy_mod_reaction)
[![Downloads](https://img.shields.io/crates/d/bevy_mod_reaction.svg)](https://crates.io/crates/bevy_mod_reaction)
[![Docs](https://docs.rs/bevy_mod_reaction/badge.svg)](https://docs.rs/bevy_mod_reaction/latest/bevy_mod_reaction/)
[![CI](https://github.com/matthunz/bevy_mod_reaction/workflows/CI/badge.svg)](https://github.com/matthunz/bevy_mod_reaction/actions)


Reactive components for Bevy.

```rs
use bevy::prelude::*;
use bevy_mod_reaction::{react, Reaction, ReactiveQuery, Scope};

fn main() {
    App::new()
        .add_plugins(DefaultPlugins)
        .add_systems(Startup, setup)
        .add_systems(Update, react)
        .run();
}

#[derive(Component)]

struct Health(i32);

#[derive(Component)]

struct Damage(i32);

#[derive(Component)]

struct Armor(i32);

fn setup(mut commands: Commands) {
    // Coarse-grained reactivity:
    // This reaction will only run when the `Health` component belonging to `scope.entity` changes.
    commands.spawn((
        Health(100),
        Reaction::derive(|scope: In<Scope>, mut query: ReactiveQuery<&Health>| {
            let health = query.get(scope.entity).unwrap();
            Damage(health.0 * 2)
        }),
    ));

    commands.spawn(Reaction::new(|_: In<Scope>, query: Query<&Damage>| {
        for dmg in &query {
            dbg!(dmg.0);
        }
    }));

    commands.spawn((
        Health(0),
        Reaction::switch(
            |scope: In<Scope>, query: Query<&Health>| {
                let dmg = query.get(scope.entity).unwrap();
                dmg.0 == 0
            },
            || Armor(50),
            || Damage(100),
        ),
    ));
}
```