pub struct Read<'a, T, F = DefaultProvider>where
T: 'a,{ /* private fields */ }
Expand description
Allows to fetch a resource in a system immutably.
If the resource isn’t strictly required, you should use Option<Read<T>>
.
Type parameters
T
: The type of the resourceF
: The setup handler (default:DefaultProvider
)
Trait Implementations
sourceimpl<'a, 'b, T> Join for &'a Read<'b, T>where
&'a T: Join,
T: Resource,
impl<'a, 'b, T> Join for &'a Read<'b, T>where
&'a T: Join,
T: Resource,
sourceunsafe fn open(self) -> (Self::Mask, Self::Value)
unsafe fn open(self) -> (Self::Mask, Self::Value)
Open this join by returning the mask and the storages. Read more
sourceunsafe fn get(v: &mut Self::Value, i: Index) -> Self::Type
unsafe fn get(v: &mut Self::Value, i: Index) -> Self::Type
Get a joined component value by a given index.
sourcefn is_unconstrained() -> bool
fn is_unconstrained() -> bool
If this
Join
typically returns all indices in the mask, then iterating over only it
or combined with other joins that are also dangerous will cause the JoinIter
/ParJoin
to
go through all indices which is usually not what is wanted and will kill performance. Read moresourceimpl<'a, 'b, T> ParJoin for &'a Read<'b, T>where
&'a T: ParJoin,
T: Resource,
impl<'a, 'b, T> ParJoin for &'a Read<'b, T>where
&'a T: ParJoin,
T: Resource,
sourcefn par_join(self) -> JoinParIter<Self>where
Self: Sized,
fn par_join(self) -> JoinParIter<Self>where
Self: Sized,
Create a joined parallel iterator over the contents.
sourceimpl<'a, T, F> SystemData<'a> for Read<'a, T, F>where
T: Resource,
F: SetupHandler<T>,
impl<'a, T, F> SystemData<'a> for Read<'a, T, F>where
T: Resource,
F: SetupHandler<T>,
sourcefn fetch(res: &'a Resources) -> Read<'a, T, F>
fn fetch(res: &'a Resources) -> Read<'a, T, F>
Fetches the system data from
Resources
. Note that this is only specified for one concrete
lifetime 'a
, you need to implement the SystemData
trait for every possible
lifetime. Read moreAuto Trait Implementations
impl<'a, T, F = DefaultProvider> !RefUnwindSafe for Read<'a, T, F>
impl<'a, T, F> Send for Read<'a, T, F>where
F: Send,
T: Sync,
impl<'a, T, F> Sync for Read<'a, T, F>where
F: Sync,
T: Sync,
impl<'a, T, F> Unpin for Read<'a, T, F>where
F: Unpin,
impl<'a, T, F = DefaultProvider> !UnwindSafe for Read<'a, T, F>
Blanket Implementations
sourceimpl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<'a, T> DynamicSystemData<'a> for Twhere
T: SystemData<'a>,
impl<'a, T> DynamicSystemData<'a> for Twhere
T: SystemData<'a>,
type Accessor = StaticAccessor<T>
type Accessor = StaticAccessor<T>
The accessor of the
SystemData
, which specifies the read and write dependencies and does
the fetching. Read moresourcefn setup(_: &StaticAccessor<T>, res: &mut Resources)
fn setup(_: &StaticAccessor<T>, res: &mut Resources)
Sets up
Resources
for fetching this system data.