Trait geng::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

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl<T, F> Deref for SyncLazy<T, F> where
    F: FnOnce() -> T, 

type Target = T

pub fn deref(&self) -> &T

impl Deref for CString

type Target = CStr

pub fn deref(&self) -> &CStr

impl Deref for OsString

type Target = OsStr

pub fn deref(&self) -> &OsStr

impl<T> Deref for AssertUnwindSafe<T>

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl Deref for PathBuf

type Target = Path

pub fn deref(&self) -> &Path

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

type Target = T

pub fn deref(&self) -> &T

impl<T, F> Deref for Lazy<T, F> where
    F: FnOnce() -> T, 

type Target = T

pub fn deref(&self) -> &T

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

type Target = VaListImpl<'f>

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

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

type Target = T

pub fn deref(&self) -> &T

impl<T> Deref for Vec<T>

type Target = [T]

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

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

type Target = T

pub fn deref(&self) -> &T

impl Deref for String

type Target = str

pub fn deref(&self) -> &str

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

type Target = B

pub fn deref(&self) -> &B

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = S

pub fn deref(&self) -> &S

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

type Target = [u8]

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

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

type Target = Vec<T>

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

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

type Target = [T]

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

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

type Target = FramebufferRead<'a>

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

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

type Target = Context<T>

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

impl Deref for Window

type Target = UnownedWindow

pub fn deref(&self) -> &UnownedWindow

impl<T> Deref for EventLoop<T>

type Target = EventLoopWindowTarget<T>

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

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

type Target = T

pub 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

pub fn deref(&self) -> &T

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

type Target = T

pub 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

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

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

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

impl Deref for ThemedPointer

type Target = WlPointer

pub fn deref(&self) -> &WlPointer

impl<T> Deref for Symbol<T>

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl Deref for Display

type Target = Proxy<WlDisplay>

pub fn deref(&self) -> &Proxy<WlDisplay>

impl<I> Deref for Attached<I> where
    I: Interface, 

type Target = I

pub fn deref(&self) -> &I

impl<I> Deref for Main<I> where
    I: Interface + AsRef<Proxy<I>> + From<Proxy<I>>, 

type Target = Attached<I>

pub fn deref(&self) -> &Attached<I>

impl Deref for WAYLAND_CLIENT_OPTION

type Target = Option<WaylandClient>

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

impl Deref for WAYLAND_CLIENT_HANDLE

type Target = &'static WaylandClient

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

impl Deref for WAYLAND_EGL_HANDLE

type Target = &'static WaylandEgl

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

impl Deref for WAYLAND_EGL_OPTION

type Target = Option<WaylandEgl>

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

impl Deref for MmapMut

type Target = [u8]

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

impl Deref for Mmap

type Target = [u8]

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

impl Deref for CursorImageBuffer

type Target = WlBuffer

pub fn deref(&self) -> &WlBuffer

impl<T> Deref for Owned<T>

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl<T> Deref for CachePadded<T>

type Target = T

pub fn deref(&self) -> &T

impl Deref for UnixReady

type Target = Ready

pub fn deref(&self) -> &Ready

impl Deref for IoVec

type Target = [u8]

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

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]

pub 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

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

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

type Target = T

pub fn deref(&self) -> &T

impl<T> Deref for CachePadded<T>

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl<T> Deref for Owned<T> where
    T: Pointable + ?Sized, 

type Target = T

pub fn deref(&self) -> &T

impl Deref for BytesMut

type Target = [u8]

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

impl Deref for Bytes

type Target = [u8]

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

impl<T, N> Deref for GenericArray<T, N> where
    N: ArrayLength<T>, 

type Target = [T]

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

impl<'s, T> Deref for SliceVec<'s, T>

type Target = [T]

#[must_use]pub fn deref(&self) -> &<SliceVec<'s, T> as Deref>::Target

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

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

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

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

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

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

impl<'a> Deref for Selem<'a>

type Target = Elem<'a>

pub fn deref(&self) -> &Elem<'a>

returns the elem of this selem

impl Deref for MilliBel

type Target = i64

pub fn deref(&self) -> &i64

impl<T> Deref for SliceDeque<T>

type Target = [T]

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

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

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

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

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Implementors

impl Deref for Error

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

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

impl Deref for Slider

type Target = WidgetCore

fn deref(&self) -> &WidgetCore

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

type Target = Waker

pub fn deref(&self) -> &Waker

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl<'_, T, U> Deref for geng::prelude::futures::lock::MappedMutexGuard<'_, T, U> where
    T: ?Sized,
    U: ?Sized, 

type Target = U

pub fn deref(&self) -> &U

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

type Target = [u8]

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

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

type Target = [u8]

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

impl<'a> Deref for Column<'a>

type Target = Vec<Box<dyn Widget + 'a>>

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

impl<'a> Deref for Row<'a>

type Target = Vec<Box<dyn Widget + 'a>>

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

impl<'a> Deref for Stack<'a>

type Target = Vec<Box<dyn Widget + 'a>>

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

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

type Target = <P as Deref>::Target

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

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

type Target = S

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

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = [T; 4]

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

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

type Target = T

pub fn deref(&self) -> &T

impl<T> Deref for Vec2<T>

type Target = [T; 2]

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

impl<T> Deref for Vec3<T>

type Target = [T; 3]

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

impl<T> Deref for Vec4<T>

type Target = [T; 4]

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

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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