Trait otter_api_tests::Deref

#[lang = "deref"]
pub trait Deref {
    type Target: ?Sized;
    #[must_use]
    pub 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]

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

Dereferences the value.

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Implementations on Foreign Types

impl<T> Deref for AssertUnwindSafe<T>

type Target = T

pub fn deref(&self) -> &T

impl Deref for OsString

type Target = OsStr

pub fn deref(&self) -> &OsStr

impl Deref for CString

type Target = CStr

pub fn deref(&self) -> &CStr

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl<T, A> Deref for Vec<T, A> where
    A: Allocator, 

type Target = [T]

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

impl Deref for String

type Target = str

pub fn deref(&self) -> &str

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl Deref for Literal

type Target = Vec<u8, Global>

pub fn deref(&self) -> &Vec<u8, Global>

impl Deref for Timestamp

type Target = SystemTime

pub fn deref(&self) -> &SystemTime

impl Deref for Duration

type Target = Duration

pub fn deref(&self) -> &Duration

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 Deref for UnixReady

type Target = Ready

pub fn deref(&self) -> &Ready

impl Deref for IoVec

type Target = [u8]

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

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

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<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<'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 Deref for TempPath

type Target = Path

pub fn deref(&self) -> &Path

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

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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 PathBuf

type Target = Path

pub fn deref(&self) -> &Path

impl Deref for AccessRecord

type Target = Arc<dyn PlayerAccessSpec + 'static>

pub fn deref(&self) -> &Arc<dyn PlayerAccessSpec + 'static>

impl Deref for GLOBAL

type Target = Global

pub fn deref(&self) -> &Global

impl Deref for GPieces

type Target = DenseSlotMap<PieceId, GPiece>

pub fn deref(&self) -> &DenseSlotMap<PieceId, GPiece>

impl Deref for Html

type Target = HtmlStr

pub fn deref(&self) -> &HtmlStr

impl Deref for HtmlLit

type Target = HtmlStr

pub fn deref(&self) -> &HtmlStr

impl Deref for IPiece

type Target = IPieceTraitObj

pub fn deref(&self) -> &IPieceTraitObj

impl Deref for LinksTable

type Target = EnumMap<LinkKind, Option<String>>

pub fn deref(&self) -> &EnumMap<LinkKind, Option<String>>

impl Deref for MgmtChannelForGame

type Target = MgmtChannel

pub fn deref(&self) -> &MgmtChannel

impl Deref for PieceRenderInstructions

type Target = PriOccultedGeneral<PosC<i32>, ZLevel>

pub fn deref(&self) -> &PriOccultedGeneral<PosC<i32>, ZLevel>

impl<'_> Deref for InstanceGuard<'_>

type Target = Instance

pub fn deref(&self) -> &Instance

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

type Target = B

pub fn deref(&self) -> &B

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

type Target = VaListImpl<'f>

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

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl<A> Deref for ArrayString<A> where
    A: Array<Item = u8> + Copy, 

type Target = str

pub fn deref(&self) -> &str

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

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

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

impl<I, A> Deref for IndexVec<I, A> where
    I: Idx, 

type Target = IndexSlice<I, [A]>

pub fn deref(&self) -> &IndexSlice<I, [A]>

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

type Target = <P as Deref>::Target

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

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

type Target = T

pub fn deref(&self) -> &<NotNan<T> 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 OrderedFloat<T> where
    T: Float, 

type Target = T

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

impl<T, F> Deref for otter_api_tests::imports::failure::_core::lazy::Lazy<T, F> where
    F: FnOnce() -> T, 

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

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

type Target = T

pub fn deref(&self) -> &T

impl<T, F> Deref for Thunk<T, F> where
    T: Sync,
    F: Sync + FnOnce() -> T, 

type Target = T

pub fn deref(&self) -> &T

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