[][src]Enum rustc_middle::ty::ConstKind

pub enum ConstKind<'tcx> {
    Param(ParamConst),
    Infer(InferConst<'tcx>),
    Bound(DebruijnIndexBoundVar),
    Placeholder(PlaceholderConst),
    Unevaluated(WithOptConstParam<DefId>, SubstsRef<'tcx>, Option<Promoted>),
    Value(ConstValue<'tcx>),
    Error(DelaySpanBugEmitted),
}

Represents a constant in Rust.

Variants

Param(ParamConst)

A const generic parameter.

Infer(InferConst<'tcx>)

Infer the value of the const.

Bound(DebruijnIndexBoundVar)

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

Placeholder(PlaceholderConst)

A placeholder const - universally quantified higher-ranked const.

Unevaluated(WithOptConstParam<DefId>, SubstsRef<'tcx>, Option<Promoted>)

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(ConstValue<'tcx>)

Used to hold computed value.

Error(DelaySpanBugEmitted)

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

Implementations

impl<'tcx> ConstKind<'tcx>[src]

pub fn try_to_value(self) -> Option<ConstValue<'tcx>>[src]

pub fn try_to_scalar(self) -> Option<Scalar>[src]

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

pub fn try_to_bool(self) -> Option<bool>[src]

pub fn try_to_machine_usize(self, tcx: TyCtxt<'tcx>) -> Option<u64>[src]

impl<'tcx> ConstKind<'tcx>[src]

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

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

pub(super) fn try_eval(
    self,
    tcx: TyCtxt<'tcx>,
    param_env: ParamEnv<'tcx>
) -> Option<Result<ConstValue<'tcx>, ErrorReported>>
[src]

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

Trait Implementations

impl<'tcx> Clone for ConstKind<'tcx>[src]

impl<'tcx> Copy for ConstKind<'tcx>[src]

impl<'tcx> Debug for ConstKind<'tcx>[src]

impl<'tcx> Decodable for ConstKind<'tcx>[src]

impl<'tcx> Encodable for ConstKind<'tcx>[src]

impl<'tcx> Eq for ConstKind<'tcx>[src]

impl<'tcx> Hash for ConstKind<'tcx>[src]

impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for ConstKind<'tcx>[src]

impl<'tcx> Ord for ConstKind<'tcx>[src]

impl<'tcx> PartialEq<ConstKind<'tcx>> for ConstKind<'tcx>[src]

impl<'tcx> PartialOrd<ConstKind<'tcx>> for ConstKind<'tcx>[src]

impl<'tcx> StructuralEq for ConstKind<'tcx>[src]

impl<'tcx> StructuralPartialEq for ConstKind<'tcx>[src]

impl<'tcx> TypeFoldable<'tcx> for ConstKind<'tcx>[src]

Auto Trait Implementations

impl<'tcx> !RefUnwindSafe for ConstKind<'tcx>

impl<'tcx> !Send for ConstKind<'tcx>

impl<'tcx> !Sync for ConstKind<'tcx>

impl<'tcx> Unpin for ConstKind<'tcx>

impl<'tcx> !UnwindSafe for ConstKind<'tcx>

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized
[src]

impl<'tcx, T> ArenaAllocatable<'tcx, ()> for T where
    T: Copy
[src]

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

impl<'a, T> Captures<'a> for T where
    T: ?Sized
[src]

impl<T> Decodable for T where
    T: UseSpecializedDecodable
[src]

impl<Ctxt, T> DepNodeParams<Ctxt> for T where
    Ctxt: DepContext,
    T: HashStable<<Ctxt as DepContext>::StableHashingContext> + Debug
[src]

impl<T> Encodable for T where
    T: UseSpecializedEncodable + ?Sized
[src]

impl<T> From<T> for T[src]

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

impl<T> MaybeResult<T> for T[src]

type Error = !

impl<'tcx, T> Subst<'tcx> for T where
    T: TypeFoldable<'tcx>, 
[src]

impl<T> ToOwned for T where
    T: Clone
[src]

type Owned = T

The resulting type after obtaining ownership.

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

impl<T> WithConstness for T[src]