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|
use ecs::actions::Actions;
use ecs::event::Event;
use ecs::{Component, Query, World};
#[derive(Component)]
struct Wool
{
remaining: u32,
}
#[derive(Component)]
struct Health
{
health: u32,
}
#[derive(Component)]
struct Name
{
name: &'static str,
}
fn sheer(query: Query<(Wool, Name)>)
{
for (mut wool, name) in &query {
if wool.remaining == 0 {
println!("{} Has no wool left", name.name);
continue;
}
// Sheer the whool
wool.remaining -= 5;
println!("Sheered 5 wool from {}", name.name);
}
}
fn feed(query: Query<(Health, Name)>)
{
for (mut health, name) in &query {
health.health += 1;
println!("Feeded {} which gained 1 health", name.name);
}
}
fn age(query: Query<(Health, Name)>, mut actions: Actions)
{
for (mut health, name) in &query {
if health.health <= 2 {
health.health = 0;
println!("{} passed away", name.name);
actions.stop();
continue;
}
health.health -= 2;
println!("{} aged and lost 2 health", name.name);
}
}
#[derive(Debug)]
struct EventA;
impl Event for EventA {}
#[derive(Debug)]
struct EventB;
impl Event for EventB {}
#[derive(Debug)]
struct EventC;
impl Event for EventC {}
fn main()
{
let mut world = World::new();
world.register_system(EventA, sheer);
world.register_system(EventB, feed);
world.register_system(EventC, age);
world.create_entity((
Wool { remaining: 30 },
Health { health: 3 },
Name { name: "Bessy" },
));
world.event_loop::<(EventA, EventB, EventC)>();
}
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