[][src]Struct rustc_middle::ty::Const

pub struct Const<'tcx> {
    pub ty: Ty<'tcx>,
    pub val: ConstKind<'tcx>,

Typed constant value.


ty: Ty<'tcx>val: ConstKind<'tcx>


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

pub fn from_anon_const(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> &'tcx Self[src]

Literals and const generic parameters are eagerly converted to a constant, everything else becomes Unevaluated.

pub fn from_opt_const_arg_anon_const(
    tcx: TyCtxt<'tcx>,
    def: WithOptConstParam<LocalDefId>
) -> &'tcx Self

pub fn from_value(
    tcx: TyCtxt<'tcx>,
    val: ConstValue<'tcx>,
    ty: Ty<'tcx>
) -> &'tcx Self

Interns the given value as a constant.

pub fn from_scalar(tcx: TyCtxt<'tcx>, val: Scalar, ty: Ty<'tcx>) -> &'tcx Self[src]

Interns the given scalar as a constant.

pub fn from_bits(
    tcx: TyCtxt<'tcx>,
    bits: u128,
    ty: ParamEnvAnd<'tcx, Ty<'tcx>>
) -> &'tcx Self

Creates a constant with the given integer value and interns it.

pub fn zero_sized(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> &'tcx Self[src]

Creates an interned zst constant.

pub fn from_bool(tcx: TyCtxt<'tcx>, v: bool) -> &'tcx Self[src]

Creates an interned bool constant.

pub fn from_usize(tcx: TyCtxt<'tcx>, n: u64) -> &'tcx Self[src]

Creates an interned usize constant.

pub fn try_eval_bits(
    tcx: TyCtxt<'tcx>,
    param_env: ParamEnv<'tcx>,
    ty: Ty<'tcx>
) -> Option<u128>

Attempts to evaluate the given constant to bits. Can fail to evaluate in the presence of generics (or erroneous code) or if the value can't be represented as bits (e.g. because it contains const generic parameters or pointers).

pub fn try_eval_bool(
    tcx: TyCtxt<'tcx>,
    param_env: ParamEnv<'tcx>
) -> Option<bool>

pub fn try_eval_usize(
    tcx: TyCtxt<'tcx>,
    param_env: ParamEnv<'tcx>
) -> Option<u64>

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

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

pub fn eval_bits(
    tcx: TyCtxt<'tcx>,
    param_env: ParamEnv<'tcx>,
    ty: Ty<'tcx>
) -> u128

Panics if the value cannot be evaluated or doesn't contain a valid integer of the given type.

pub fn eval_usize(&self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> u64[src]

Panics if the value cannot be evaluated or doesn't contain a valid usize.

Trait Implementations

impl<'tcx> Borrow<Const<'tcx>> for Interned<'tcx, Const<'tcx>>[src]

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

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

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

impl<'tcx, __D: TyDecoder<'tcx>> Decodable<__D> for Const<'tcx>[src]

impl<'tcx> Display for &'tcx Const<'tcx>[src]

impl<'tcx, __E: TyEncoder<'tcx>> Encodable<__E> for Const<'tcx>[src]

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

impl<'tcx> EqUnifyValue for &'tcx Const<'tcx>[src]

impl<'tcx> From<&'tcx Const<'tcx>> for GenericArg<'tcx>[src]

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

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

impl<'tcx> Key for &'tcx Const<'tcx>[src]

type CacheSelector = DefaultCacheSelector

impl<'a, 'tcx> Lift<'tcx> for &'a Const<'a>[src]

type Lifted = &'tcx Const<'tcx>

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

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

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

impl<'tcx, P: Printer<'tcx>> Print<'tcx, P> for &'tcx Const<'tcx>[src]

type Output = P::Const

type Error = P::Error

impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for Const<'tcx>[src]

impl<'tcx> Relate<'tcx> for &'tcx Const<'tcx>[src]

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

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

impl<'tcx> TypeFoldable<'tcx> for &'tcx Const<'tcx>[src]

Auto Trait Implementations

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

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

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

impl<'tcx> Unpin for Const<'tcx>

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

Blanket Implementations

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

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

impl<T> Borrow<T> for T where
    T: ?Sized

impl<T> BorrowMut<T> for T where
    T: ?Sized

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

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

impl<T, U> Into<U> for T where
    U: From<T>, 

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

type Error = !

impl<T> ToOwned for T where
    T: Clone

type Owned = T

The resulting type after obtaining ownership.

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 

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

The type returned in the event of a conversion error.

impl<T> WithConstness for T[src]