Struct PriorityEventReader 

pub struct PriorityEventReader<'w, 's, E: PriorityEvent> { /* private fields */ }

Implementations

impl<E: PriorityEvent> PriorityEventReader<'_, '_, E>

pub fn iter_prio_range( &mut self, max: u32, min: u32, ) -> impl Iterator<Item = E> + '_

Iterates over events this reader has not seen yet, while also clearing them. Will not remove any events of priority lower than min (0 is highest, inf is lowest) but will discard events of higher priority i.e. will handle events in the priority range [min,max] (inclusive)

pub fn len(&self) -> usize

Determines the number of events available to be read, without consuming any

pub fn is_empty(&self) -> bool

Determines if there are any events to be read, without consuming any.

Trait Implementations

impl<E: PriorityEvent> SystemParam for PriorityEventReader<'_, '_, E>

type State = FetchState<E>

Used to store data which persists across invocations of a system.

type Item<'w, 's> = PriorityEventReader<'w, 's, E>

The item type returned when constructing this system param. The value of this associated type should be Self, instantiated with new lifetimes.

fn init_state(world: &mut World, system_meta: &mut SystemMeta) -> Self::State

Registers any World access used by this SystemParam and creates a new instance of this param’s State.

unsafe fn new_archetype( state: &mut Self::State, archetype: &Archetype, system_meta: &mut SystemMeta, )

For the specified Archetype, registers the components accessed by this SystemParam (if applicable).a

fn apply(state: &mut Self::State, system_meta: &SystemMeta, world: &mut World)

Applies any deferred mutations stored in this SystemParam’s state. This is used to apply Commands during apply_deferred.

fn queue( state: &mut Self::State, system_meta: &SystemMeta, world: DeferredWorld<'_>, )

Queues any deferred mutations to be applied at the next apply_deferred.

unsafe fn validate_param<'w, 's>( state: &'s Self::State, system_meta: &SystemMeta, world: UnsafeWorldCell<'w>, ) -> bool

Validates that the param can be acquired by the get_param. Built-in executors use this to prevent systems with invalid params from running. For nested SystemParams validation will fail if any delegated validation fails.

unsafe fn get_param<'w, 's>( state: &'s mut Self::State, system_meta: &SystemMeta, world: UnsafeWorldCell<'w>, change_tick: Tick, ) -> Self::Item<'w, 's>

Creates a parameter to be passed into a SystemParamFunction.

impl<'w, 's, E: PriorityEvent> ReadOnlySystemParam for PriorityEventReader<'w, 's, E>

where ResMut<'w, PriorityEvents<E>>: ReadOnlySystemParam, PhantomData<&'s usize>: ReadOnlySystemParam,