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

pub enum ConstKind<'tcx> {
    Param(ParamConst),
    Infer(InferConst<'tcx>),
    Bound(DebruijnIndex, BoundVar),
    Placeholder(PlaceholderConst<'tcx>),
    Unevaluated(Unevaluated<'tcx>),
    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(DebruijnIndex, BoundVar)

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

Placeholder(PlaceholderConst<'tcx>)

A placeholder const - universally quantified higher-ranked const.

Unevaluated(Unevaluated<'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(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>

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

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

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

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>

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<'tcx>> Decodable<__D> for ConstKind<'tcx>

fn decode(__decoder: &mut __D) -> Result<Self, <__D as Decoder>::Error>

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

fn encode(&self, __encoder: &mut __E) -> Result<(), <__E as Encoder>::Error>

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, 

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.

#[must_use]

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

Compares and returns the maximum of two values.

#[must_use]

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

Compares and returns the minimum of two values.

#[must_use]

fn clamp(self, min: Self, max: Self) -> 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: &ConstKind<'tcx>) -> bool

This method tests for !=.

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.

#[must_use]

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

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

#[must_use]

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

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

#[must_use]

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

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

#[must_use]

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<'tcx> for ConstKind<'tcx>

fn super_fold_with<F: TypeFolder<'tcx>>(self, folder: &mut F) -> Self

fn super_visit_with<V: TypeVisitor<'tcx>>(
    &self,
    visitor: &mut V
) -> ControlFlow<V::BreakTy>

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

fn visit_with<V: TypeVisitor<'tcx>>(
    &self,
    visitor: &mut V
) -> ControlFlow<V::BreakTy>

fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool

Returns true if self has any late-bound regions that are either bound by binder or bound by some binder outside of binder. If binder is ty::INNERMOST, this indicates whether there are any late-bound regions that appear free.

fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool

Returns true if this self has any regions that escape binder (and hence are not bound by it).

fn has_escaping_bound_vars(&self) -> bool

fn has_type_flags(&self, flags: TypeFlags) -> bool

fn has_projections(&self) -> bool

fn has_opaque_types(&self) -> bool

fn references_error(&self) -> bool

fn has_param_types_or_consts(&self) -> bool

fn has_infer_regions(&self) -> bool

fn has_infer_types(&self) -> bool

fn has_infer_types_or_consts(&self) -> bool

fn needs_infer(&self) -> bool

fn has_placeholders(&self) -> bool

fn needs_subst(&self) -> bool

fn has_free_regions(&self) -> bool

“Free” regions in this context means that it has any region that is not (a) erased or (b) late-bound.

fn has_erased_regions(&self) -> bool

fn has_erasable_regions(&self) -> bool

True if there are any un-erased free regions.

fn is_global(&self) -> bool

Indicates whether this value references only ‘global’ generic parameters that are the same regardless of what fn we are in. This is used for caching.

fn has_late_bound_regions(&self) -> bool

True if there are any late-bound regions

fn still_further_specializable(&self) -> bool

Indicates whether this value still has parameters/placeholders/inference variables which could be replaced later, in a way that would change the results of impl specialization.

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

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

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

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