Enum BorrowKind

pub enum BorrowKind {
    Shared,
    Fake(FakeBorrowKind),
    Mut {
        kind: MutBorrowKind,
    },
}

Variants

Shared

Data must be immutable and is aliasable.

Fake(FakeBorrowKind)

An immutable, aliasable borrow that is discarded after borrow-checking. Can behave either like a normal shared borrow or like a special shallow borrow (see FakeBorrowKind).

This is used when lowering index expressions and matches. This is used to prevent code like the following from compiling:

let mut x: &[_] = &[[0, 1]];
let y: &[_] = &[];
let _ = x[0][{x = y; 1}];

let mut x = &Some(0);
match *x {
    None => (),
    Some(_) if { x = &None; false } => (),
    Some(_) => (),
}

We can also report errors with this kind of borrow differently.

Mut

Data is mutable and not aliasable.

Fields

kind: MutBorrowKind

Implementations

impl BorrowKind

pub fn mutability(&self) -> Mutability

pub fn allows_two_phase_borrow(&self) -> bool

Returns whether borrows represented by this kind are allowed to be split into separate Reservation and Activation phases.

pub fn to_mutbl_lossy(self) -> Mutability

Trait Implementations

impl Clone for BorrowKind

fn clone(&self) -> BorrowKind

Returns a duplicate of the value.

const fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BorrowKind

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

Formats the value using the given formatter.

impl<'tcx, __D: TyDecoder<'tcx>> Decodable<__D> for BorrowKind

fn decode(__decoder: &mut __D) -> Self

impl<'tcx, __E: TyEncoder<'tcx>> Encodable<__E> for BorrowKind

fn encode(&self, __encoder: &mut __E)

impl Hash for BorrowKind

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<'__ctx> HashStable<StableHashingContext<'__ctx>> for BorrowKind

fn hash_stable( &self, __hcx: &mut StableHashingContext<'__ctx>, __hasher: &mut StableHasher, )

impl Ord for BorrowKind

fn cmp(&self, other: &BorrowKind) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for BorrowKind

fn eq(&self, other: &BorrowKind) -> bool

Tests for self and other values to be equal, and is used by ==.

const fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for BorrowKind

fn partial_cmp(&self, other: &BorrowKind) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for BorrowKind

fn try_fold_with<F: FallibleTypeFolder<TyCtxt<'tcx>>>( self, _: &mut F, ) -> Result<Self, F::Error>

The entry point for folding. To fold a value t with a folder f call: t.try_fold_with(f).

fn fold_with<F: TypeFolder<TyCtxt<'tcx>>>(self, _: &mut F) -> Self

The entry point for folding. To fold a value t with a folder f call: t.fold_with(f).

impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for BorrowKind

fn visit_with<F: TypeVisitor<TyCtxt<'tcx>>>(&self, _: &mut F) -> F::Result

The entry point for visiting. To visit a value t with a visitor v call: t.visit_with(v).

impl Copy for BorrowKind

impl Eq for BorrowKind

impl StructuralPartialEq for BorrowKind

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 2 bytes

Size for each variant:

• Shared: 0 bytes
• Fake: 1 byte
• Mut: 1 byte