Trait geng_core::prelude::structopt::lazy_static::__Deref

#[lang = "deref"]pub trait __Deref {
    type Target: ?Sized;
#[must_use]    fn deref(&self) -> &Self::Target;
}

Used for immutable dereferencing operations, like *v.

In addition to being used for explicit dereferencing operations with the (unary) * operator in immutable contexts, Deref is also used implicitly by the compiler in many circumstances. This mechanism is called 'Deref coercion'. In mutable contexts, DerefMut is used.

Implementing Deref for smart pointers makes accessing the data behind them convenient, which is why they implement Deref. On the other hand, the rules regarding Deref and DerefMut were designed specifically to accommodate smart pointers. Because of this, Deref should only be implemented for smart pointers to avoid confusion.

For similar reasons, this trait should never fail. Failure during dereferencing can be extremely confusing when Deref is invoked implicitly.

More on Deref coercion

If T implements Deref<Target = U>, and x is a value of type T, then:

• In immutable contexts, *x (where T is neither a reference nor a raw pointer) is equivalent to *Deref::deref(&x).
• Values of type &T are coerced to values of type &U
• T implicitly implements all the (immutable) methods of the type U.

For more details, visit the chapter in The Rust Programming Language as well as the reference sections on the dereference operator, method resolution and type coercions.

Examples

A struct with a single field which is accessible by dereferencing the struct.

use std::ops::Deref;

struct DerefExample<T> {
    value: T
}

impl<T> Deref for DerefExample<T> {
    type Target = T;

    fn deref(&self) -> &Self::Target {
        &self.value
    }
}

let x = DerefExample { value: 'a' };
assert_eq!('a', *x);

Associated Types

type Target: ?Sized

The resulting type after dereferencing.

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Required methods

#[must_use]fn deref(&self) -> &Self::Target

Dereferences the value.

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Implementations on Foreign Types

impl<'_, T> Deref for MutexGuard<'_, T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'_, T> Deref for RwLockReadGuard<'_, T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl Deref for OsString

type Target = OsStr

fn deref(&self) -> &OsStr

impl<'_, T> Deref for RwLockWriteGuard<'_, T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl Deref for PathBuf

type Target = Path

fn deref(&self) -> &Path

impl<T> Deref for AssertUnwindSafe<T>

type Target = T

fn deref(&self) -> &T

impl Deref for CString

type Target = CStr

fn deref(&self) -> &CStr

impl<'_, T> Deref for &'_ mut T where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<T> Deref for ManuallyDrop<T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'_, T> Deref for &'_ T where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, 'f> Deref for VaList<'a, 'f> where
    'f: 'a, 

type Target = VaListImpl<'f>

fn deref(&self) -> &VaListImpl<'f>

impl<'_, B> Deref for Cow<'_, B> where
    B: ToOwned + ?Sized, 

type Target = B

fn deref(&self) -> &B

impl Deref for String

type Target = str

fn deref(&self) -> &str

impl<T> Deref for Box<T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'_, T> Deref for PeekMut<'_, T> where
    T: Ord, 

type Target = T

fn deref(&self) -> &T

impl<T> Deref for Vec<T>

type Target = [T]

fn deref(&self) -> &[T]

impl<'input, Endian> Deref for EndianSlice<'input, Endian> where
    Endian: Endianity, 

type Target = [u8]

fn deref(&self) -> &<EndianSlice<'input, Endian> as Deref>::Target

impl<'a, S> Deref for ANSIGenericString<'a, S> where
    S: 'a + ToOwned + ?Sized,
    <S as ToOwned>::Owned: Debug, 

type Target = S

fn deref(&self) -> &S

impl<'a> Deref for Framebuffer<'a>

type Target = FramebufferRead<'a>

fn deref(&self) -> &<Framebuffer<'a> as Deref>::Target

impl<'a, T> Deref for VertexBufferSlice<'a, T> where
    T: 'a + Vertex, 

type Target = [T]

fn deref(&self) -> &<VertexBufferSlice<'a, T> as Deref>::Target

impl<T> Deref for VertexBuffer<T> where
    T: Vertex, 

type Target = Vec<T>

fn deref(&self) -> &Vec<T>

impl<T, W> Deref for ContextWrapper<T, W> where
    T: ContextCurrentState, 

type Target = Context<T>

fn deref(&self) -> &<ContextWrapper<T, W> as Deref>::Target

impl<T> Deref for EventLoop<T>

type Target = EventLoopWindowTarget<T>

fn deref(&self) -> &EventLoopWindowTarget<T>

impl Deref for Window

type Target = UnownedWindow

fn deref(&self) -> &UnownedWindow

impl<'a, T> Deref for XSmartPointer<'a, T>

type Target = T

fn deref(&self) -> &T

impl<'a, R, T> Deref for RwLockWriteGuard<'a, R, T> where
    R: 'a + RawRwLock,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, R, T> Deref for RwLockReadGuard<'a, R, T> where
    R: 'a + RawRwLock,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, R, T> Deref for MappedMutexGuard<'a, R, T> where
    R: 'a + RawMutex,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, R, G, T> Deref for ReentrantMutexGuard<'a, R, G, T> where
    G: 'a + GetThreadId,
    R: 'a + RawMutex,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, R, T> Deref for MappedRwLockReadGuard<'a, R, T> where
    R: 'a + RawRwLock,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, R, T> Deref for RwLockUpgradableReadGuard<'a, R, T> where
    R: 'a + RawRwLockUpgrade,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, R, T> Deref for MutexGuard<'a, R, T> where
    R: 'a + RawMutex,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, R, G, T> Deref for MappedReentrantMutexGuard<'a, R, G, T> where
    G: 'a + GetThreadId,
    R: 'a + RawMutex,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a, R, T> Deref for MappedRwLockWriteGuard<'a, R, T> where
    R: 'a + RawRwLock,
    T: 'a + ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<T, F, S> Deref for ScopeGuard<T, F, S> where
    F: FnOnce(T),
    S: Strategy, 

type Target = T

fn deref(&self) -> &T

impl<A> Deref for SmallVec<A> where
    A: Array, 

type Target = [<A as Array>::Item]

fn deref(&self) -> &[<A as Array>::Item]

impl Deref for ThemedPointer

type Target = WlPointer

fn deref(&self) -> &WlPointer

impl Deref for AutoPointer

type Target = WlPointer

fn deref(&self) -> &WlPointer

impl<'lib, T> Deref for Symbol<'lib, T>

type Target = T

fn deref(&self) -> &T

impl<T> Deref for Symbol<T>

type Target = T

fn deref(&self) -> &T

impl<'a> Deref for SharedBytes<'a>

type Target = [u8]

fn deref(&self) -> &[u8]

impl<T> Deref for NotNan<T> where
    T: FloatCore, 

type Target = T

fn deref(&self) -> &<NotNan<T> as Deref>::Target

impl<T> Deref for OrderedFloat<T> where
    T: FloatCore, 

type Target = T

fn deref(&self) -> &<OrderedFloat<T> as Deref>::Target

impl<T> Deref for Owned<T>

type Target = T

fn deref(&self) -> &T

impl<'a, T> Deref for ShardedLockWriteGuard<'a, T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<T> Deref for CachePadded<T>

type Target = T

fn deref(&self) -> &T

impl<'a, T> Deref for ShardedLockReadGuard<'a, T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl Deref for Mmap

type Target = [u8]

fn deref(&self) -> &[u8]

impl Deref for MmapMut

type Target = [u8]

fn deref(&self) -> &[u8]

impl Deref for Display

type Target = WlDisplay

fn deref(&self) -> &WlDisplay

impl<'a> Deref for CursorImageBuffer<'a>

type Target = WlBuffer

fn deref(&self) -> &WlBuffer

impl<E> Deref for Source<E> where
    E: EventSource, 

type Target = E

fn deref(&self) -> &E

impl Deref for UnixReady

type Target = Ready

fn deref(&self) -> &Ready

impl Deref for IoVec

type Target = [u8]

fn deref(&self) -> &[u8]

impl Deref for WAYLAND_CURSOR_OPTION

type Target = Option<WaylandCursor>

fn deref(&self) -> &Option<WaylandCursor>

impl Deref for WAYLAND_CLIENT_OPTION

type Target = Option<WaylandClient>

fn deref(&self) -> &Option<WaylandClient>

impl Deref for WAYLAND_CURSOR_HANDLE

type Target = &'static WaylandCursor

fn deref(&self) -> &&'static WaylandCursor

impl Deref for WAYLAND_CLIENT_HANDLE

type Target = &'static WaylandClient

fn deref(&self) -> &&'static WaylandClient

impl Deref for WAYLAND_EGL_HANDLE

type Target = &'static WaylandEgl

fn deref(&self) -> &&'static WaylandEgl

impl Deref for WAYLAND_EGL_OPTION

type Target = Option<WaylandEgl>

fn deref(&self) -> &Option<WaylandEgl>

impl<'lib, T> Deref for Symbol<'lib, T>

type Target = T

fn deref(&self) -> &T

impl<T> Deref for Symbol<T>

type Target = T

fn deref(&self) -> &T

impl<P, Container> Deref for ImageBuffer<P, Container> where
    Container: Deref<Target = [<P as Pixel>::Subpixel]>,
    P: Pixel + 'static,
    <P as Pixel>::Subpixel: 'static, 

type Target = [<P as Pixel>::Subpixel]

fn deref(&self) -> &<ImageBuffer<P, Container> as Deref>::Target

impl<L, R> Deref for Either<L, R> where
    L: Deref,
    R: Deref<Target = <L as Deref>::Target>, 

type Target = <L as Deref>::Target

fn deref(&self) -> &<Either<L, R> as Deref>::Target

impl<'a, T> Deref for InputBuffer<'a, T> where
    T: Sample, 

type Target = [T]

fn deref(&self) -> &[T]

impl<'a, T> Deref for OutputBuffer<'a, T> where
    T: Sample, 

type Target = [T]

fn deref(&self) -> &[T]

impl<A> Deref for TinyVec<A> where
    A: Array, 

type Target = [<A as Array>::Item]

#[must_use]fn deref(&self) -> &<TinyVec<A> as Deref>::Target

impl<A> Deref for ArrayVec<A> where
    A: Array, 

type Target = [<A as Array>::Item]

#[must_use]fn deref(&self) -> &<ArrayVec<A> as Deref>::Target

impl<T> Deref for SliceDeque<T>

type Target = [T]

fn deref(&self) -> &<SliceDeque<T> as Deref>::Target

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Implementors

impl Deref for Error

type Target = dyn Error + 'static + Sync + Send

fn deref(&self) -> &<Error as Deref>::Target

impl<'_> Deref for WakerRef<'_>

type Target = Waker

fn deref(&self) -> &Waker

impl<'_, T> Deref for geng_core::prelude::futures::lock::MutexGuard<'_, T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'_, T> Deref for Ref<'_, T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'_, T> Deref for RefMut<'_, T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<'a> Deref for IoSlice<'a>

type Target = [u8]

fn deref(&self) -> &[u8]

impl<'a> Deref for IoSliceMut<'a>

type Target = [u8]

fn deref(&self) -> &[u8]

impl<P> Deref for Pin<P> where
    P: Deref, 

type Target = <P as Deref>::Target

fn deref(&self) -> &<P as Deref>::Target

impl<S> Deref for BlockingStream<S> where
    S: Unpin + Stream, 

type Target = S

fn deref(&self) -> &<BlockingStream<S> as Deref>::Target

impl<T> Deref for Arc<T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<T> Deref for AutoSave<T> where
    T: Serialize, 

type Target = T

fn deref(&self) -> &T

impl<T> Deref for Color<T> where
    T: ColorComponent, 

type Target = [T; 4]

fn deref(&self) -> &[T; 4]

impl<T> Deref for Rc<T> where
    T: ?Sized, 

type Target = T

fn deref(&self) -> &T

impl<T> Deref for Vec2<T>

type Target = [T; 2]

fn deref(&self) -> &[T; 2]

impl<T> Deref for Vec3<T>

type Target = [T; 3]

fn deref(&self) -> &[T; 3]

impl<T> Deref for Vec4<T>

type Target = [T; 4]

fn deref(&self) -> &[T; 4]

impl<T, F> Deref for geng_core::prelude::once_cell::sync::Lazy<T, F> where
    F: FnOnce() -> T, 

type Target = T

fn deref(&self) -> &T

impl<T, F> Deref for geng_core::prelude::once_cell::unsync::Lazy<T, F> where
    F: FnOnce() -> T, 

type Target = T

fn deref(&self) -> &T

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