Enum rustc_middle::ty::consts::kind::ConstKind

pub enum ConstKind<'tcx> {
    Param(ParamConst),
    Infer(InferConst<'tcx>),
    Bound(DebruijnIndex, BoundVar),
    Placeholder(PlaceholderConst<'tcx>),
    Unevaluated(UnevaluatedConst<'tcx>),
    Value(ValTree<'tcx>),
    Error(ErrorGuaranteed),
    Expr(Expr<'tcx>),
}

Represents a constant in Rust.

Variants

Param(ParamConst)

A const generic parameter.

Infer(InferConst<'tcx>)

Infer the value of the const.

Bound(DebruijnIndex, BoundVar)

Bound const variable, used only when preparing a trait query.

Placeholder(PlaceholderConst<'tcx>)

A placeholder const - universally quantified higher-ranked const.

Unevaluated(UnevaluatedConst<'tcx>)

Used in the HIR by using Unevaluated everywhere and later normalizing to one of the other variants when the code is monomorphic enough for that.

Value(ValTree<'tcx>)

Used to hold computed value.

Error(ErrorGuaranteed)

A placeholder for a const which could not be computed; this is propagated to avoid useless error messages.

Expr(Expr<'tcx>)

Expr which contains an expression which has partially evaluated items.

Implementations

impl<'tcx> ConstKind<'tcx>

pub fn try_to_value(self) -> Option<ValTree<'tcx>>

pub fn try_to_scalar(self) -> Option<Scalar<AllocId>>

pub fn try_to_scalar_int(self) -> Option<ScalarInt>

pub fn try_to_bits(self, size: Size) -> Option<u128>

pub fn try_to_bool(self) -> Option<bool>

pub fn try_to_target_usize(self, tcx: TyCtxt<'tcx>) -> Option<u64>

impl<'tcx> ConstKind<'tcx>

pub fn eval(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> Self

Tries to evaluate the constant if it is Unevaluated. If that doesn’t succeed, return the unevaluated constant.

pub fn try_eval_for_mir( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<Result<ConstValue<'tcx>, ErrorGuaranteed>>

Tries to evaluate the constant if it is Unevaluated. If that isn’t possible or necessary return None.

pub fn try_eval_for_typeck( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<Result<ValTree<'tcx>, ErrorGuaranteed>>

Tries to evaluate the constant if it is Unevaluated. If that isn’t possible or necessary return None.

fn try_eval_inner( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>, eval_mode: EvalMode ) -> Option<Result<EvalResult<'tcx>, ErrorGuaranteed>>

Trait Implementations

impl<'tcx> Clone for ConstKind<'tcx>

fn clone(&self) -> ConstKind<'tcx>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'tcx> Debug for ConstKind<'tcx>

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

Formats the value using the given formatter.

impl<'tcx, __D: TyDecoder<I = TyCtxt<'tcx>>> Decodable<__D> for ConstKind<'tcx>

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

impl<'tcx, __E: TyEncoder<I = TyCtxt<'tcx>>> Encodable<__E> for ConstKind<'tcx>

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

impl<'tcx> From<(DebruijnIndex, BoundVar)> for ConstKind<'tcx>

fn from(original: (DebruijnIndex, BoundVar)) -> ConstKind<'tcx>

Converts to this type from the input type.

impl<'tcx> From<ConstVid<'tcx>> for ConstKind<'tcx>

fn from(const_vid: ConstVid<'tcx>) -> Self

Converts to this type from the input type.

impl<'tcx> From<Expr<'tcx>> for ConstKind<'tcx>

fn from(original: Expr<'tcx>) -> ConstKind<'tcx>

Converts to this type from the input type.

impl<'tcx> From<InferConst<'tcx>> for ConstKind<'tcx>

fn from(original: InferConst<'tcx>) -> ConstKind<'tcx>

Converts to this type from the input type.

impl<'tcx> From<ParamConst> for ConstKind<'tcx>

fn from(original: ParamConst) -> ConstKind<'tcx>

Converts to this type from the input type.

impl<'tcx> From<Placeholder<BoundVar>> for ConstKind<'tcx>

fn from(original: PlaceholderConst<'tcx>) -> ConstKind<'tcx>

Converts to this type from the input type.

impl<'tcx> From<UnevaluatedConst<'tcx>> for ConstKind<'tcx>

fn from(original: UnevaluatedConst<'tcx>) -> ConstKind<'tcx>

Converts to this type from the input type.

impl<'tcx> From<ValTree<'tcx>> for ConstKind<'tcx>

fn from(original: ValTree<'tcx>) -> ConstKind<'tcx>

Converts to this type from the input type.

impl<'tcx> Hash for ConstKind<'tcx>

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<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for ConstKind<'tcx>

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

impl<'tcx> Ord for ConstKind<'tcx>

fn cmp(&self, other: &ConstKind<'tcx>) -> Ordering

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl<'tcx> PartialEq<ConstKind<'tcx>> for ConstKind<'tcx>

fn eq(&self, other: &ConstKind<'tcx>) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

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

impl<'tcx> PartialOrd<ConstKind<'tcx>> for ConstKind<'tcx>

fn partial_cmp(&self, other: &ConstKind<'tcx>) -> Option<Ordering>

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

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

fn try_fold_with<__F: FallibleTypeFolder<TyCtxt<'tcx>>>( self, __folder: &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>(self, folder: &mut F) -> Selfwhere F: TypeFolder<I>,

A convenient alternative to try_fold_with for use with infallible folders. Do not override this method, to ensure coherence with try_fold_with.

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

fn visit_with<__V: TypeVisitor<TyCtxt<'tcx>>>( &self, __visitor: &mut __V ) -> ControlFlow<__V::BreakTy>

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

impl<'tcx> Copy for ConstKind<'tcx>

impl<'tcx> Eq for ConstKind<'tcx>

impl<'tcx> StructuralEq for ConstKind<'tcx>

impl<'tcx> StructuralPartialEq for ConstKind<'tcx>

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:32 bytes

Size for each variant:

• Param: 8 bytes
• Infer: 8 bytes
• Bound: 8 bytes
• Placeholder: 8 bytes
• Unevaluated: 20 bytes
• Value: 28 bytes
• Error: 0 bytes
• Expr: 28 bytes