Macro bbecs::query

macro_rules! query {
    ($world:expr, $query:expr, $($name:expr),*) => { ... };
}

Helper to query for components in the world. We have to give a query variable that will last longer than the macro for this to work.

use bbecs::query;
use bbecs::world::{World, ENTITY_ID, WorldMethods, DataWrapper};
use bbecs::components::CastComponents;

// creating the world and adding an entity for us to query later
let mut world = World::new();
    world.register("size").unwrap();
    world
        .spawn_entity()
        .unwrap()
        .with_component("size", 15.0_f32)
        .unwrap();

// Now we are querying for the size and an entity id which is automatically added to all entities
let query;
let (sizes, entity_ids) = query!(world, query, "size", ENTITY_ID);

for (index, size) in sizes.iter().enumerate() {
    let size: &DataWrapper<f32> = size.cast().unwrap();
    let entity_id: &DataWrapper<u32> = entity_ids[index].cast().unwrap();

    assert_eq!(*size.borrow(), 15.0);
    assert_eq!(*entity_id.borrow(), 0);
}