Struct bevy_ecs::change_detection::Res

pub struct Res<'w, T: ?Sized + Resource> { /* private fields */ }

Shared borrow of a Resource.

See the Resource documentation for usage.

If you need a unique mutable borrow, use ResMut instead.

Panics

Panics when used as a SystemParameter if the resource does not exist.

Use Option<Res<T>> instead if the resource might not always exist.

Implementations

impl<'w, T: Resource> Res<'w, T>

pub fn clone(this: &Self) -> Self

pub fn into_inner(self) -> &'w T

Due to lifetime limitations of the Deref trait, this method can be used to obtain a reference of the Resource with a lifetime bound to 'w instead of the lifetime of the struct itself.

Trait Implementations

impl<'w, T: Resource> AsRef<T> for Res<'w, T>

fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.

impl<'w, T> Debug for Res<'w, T>where T: Debug + ?Sized + Resource,

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'w, T: ?Sized + Resource> Deref for Res<'w, T>

type Target = T

The resulting type after dereferencing.

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

Dereferences the value.

impl<'w, T: ?Sized + Resource> DetectChanges for Res<'w, T>

fn is_added(&self) -> bool

Returns true if this value was added after the system last ran.

fn is_changed(&self) -> bool

Returns true if this value was added or mutably dereferenced after the system last ran.

fn last_changed(&self) -> u32

Returns the change tick recording the time this data was most recently changed.

impl<'w, T: Resource> From<ResMut<'w, T>> for Res<'w, T>

fn from(res: ResMut<'w, T>) -> Self

Converts to this type from the input type.

impl<'w, 'a, T: Resource> IntoIterator for &'a Res<'w, T>where &'a T: IntoIterator,

type Item = <&'a T as IntoIterator>::Item

The type of the elements being iterated over.

type IntoIter = <&'a T 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<'a, T: Resource> SystemParam for Res<'a, T>

type State = ComponentId

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

type Item<'w, 's> = Res<'w, T>

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 get_param<'w, 's>( component_id: &'s mut Self::State, system_meta: &SystemMeta, world: &'w World, change_tick: u32 ) -> Self::Item<'w, 's>

Safety

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).

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_system_buffers.

impl<'a, T: Resource> ReadOnlySystemParam for Res<'a, T>