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Struct bevy::ecs::system::RemovedComponents[]

pub struct RemovedComponents<'a, T> where
    T: Component
{ /* fields omitted */ }
Expand description

A SystemParam that grants access to the entities that had their T Component removed.

Note that this does not allow you to see which data existed before removal. If you need this, you will need to track the component data value on your own, using a regularly scheduled system that requests Query<(Entity, &T), Changed<T>> and stores the data somewhere safe to later cross-reference.

If you are using bevy_ecs as a standalone crate, note that the RemovedComponents list will not be automatically cleared for you, and will need to be manually flushed using World::clear_trackers

For users of bevy itself, this is automatically done in a system added by MinimalPlugins or DefaultPlugins at the end of each pass of the game loop.

Examples

Basic usage:


fn react_on_removal(removed: RemovedComponents<MyComponent>) {
    removed.iter().for_each(|removed_entity| println!("{:?}", removed_entity));
}

Implementations

Returns an iterator over the entities that had their T Component removed.

Trait Implementations

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