Struct ExtractWorld 

pub struct ExtractWorld<'w, 's, P>
where
    P: ReadOnlySystemParam + 'static,
{ /* private fields */ }

A helper for accessing MainWorld content using a system parameter. ExtractWorld is used to get data from the main world during crate::core::Extract. Note that the system parameter P must implement ReadOnlySystemParam, as the main world is only accessible for reading in this context.

Example

fn extract(mut commands: Commands, clouds: ExtractWorld<Query<Entity, With<Cloud>>>) {
    /* (...) */
}

Trait Implementations

impl<'w, 's, P> Deref for ExtractWorld<'w, 's, P>

where P: ReadOnlySystemParam,

type Target = <P as SystemParam>::Item<'w, 's>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<P> DerefMut for ExtractWorld<'_, '_, P>

where P: ReadOnlySystemParam,

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<'a, 'w, 's, P> IntoIterator for &'a ExtractWorld<'w, 's, P>

where P: ReadOnlySystemParam, &'a SystemParamItem<'w, 's, P>: IntoIterator,

type Item = <&'a <P as SystemParam>::Item<'w, 's> as IntoIterator>::Item

The type of the elements being iterated over.

type IntoIter = <&'a <P as SystemParam>::Item<'w, 's> as IntoIterator>::IntoIter

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<P> SystemParam for ExtractWorld<'_, '_, P>

where P: ReadOnlySystemParam,

type State = ExtractState<P>

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

type Item<'w, 's> = ExtractWorld<'w, 's, P>

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

fn init_access( state: &Self::State, system_meta: &mut SystemMeta, component_access_set: &mut FilteredAccessSet, world: &mut World, )

Registers any [World] access used by this [SystemParam]

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

Creates a new instance of this param’s State.

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.

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 ApplyDeferred.

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

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

unsafe fn validate_param( state: &mut Self::State, system_meta: &SystemMeta, world: UnsafeWorldCell<'_>, ) -> Result<(), SystemParamValidationError>

Validates that the param can be acquired by the get_param.

impl<P> ReadOnlySystemParam for ExtractWorld<'_, '_, P>

where P: ReadOnlySystemParam,