Struct rustc_middle::ty::Const
source · pub struct Const<'tcx>(pub(super) Interned<'tcx, ConstData<'tcx>>);
Expand description
Use this rather than ConstData
, whenever possible.
Tuple Fields§
§0: Interned<'tcx, ConstData<'tcx>>
Implementations§
source§impl<'tcx> Const<'tcx>
impl<'tcx> Const<'tcx>
sourcepub fn walk(self) -> TypeWalker<'tcx> ⓘ
pub fn walk(self) -> TypeWalker<'tcx> ⓘ
Iterator that walks self
and any types reachable from
self
, in depth-first order. Note that just walks the types
that appear in self
, it does not descend into the fields of
structs or variants. For example:
isize => { isize }
Foo<Bar<isize>> => { Foo<Bar<isize>>, Bar<isize>, isize }
[isize] => { [isize], isize }
source§impl<'tcx> Const<'tcx>
impl<'tcx> Const<'tcx>
pub fn ty(self) -> Ty<'tcx>
pub fn kind(self) -> ConstKind<'tcx>
pub fn new( tcx: TyCtxt<'tcx>, kind: ConstKind<'tcx>, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_param( tcx: TyCtxt<'tcx>, param: ParamConst, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_var( tcx: TyCtxt<'tcx>, infer: ConstVid<'tcx>, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_fresh(tcx: TyCtxt<'tcx>, fresh: u32, ty: Ty<'tcx>) -> Const<'tcx>
pub fn new_infer( tcx: TyCtxt<'tcx>, infer: InferConst<'tcx>, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_bound( tcx: TyCtxt<'tcx>, debruijn: DebruijnIndex, var: BoundVar, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_placeholder( tcx: TyCtxt<'tcx>, placeholder: PlaceholderConst<'tcx>, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_unevaluated( tcx: TyCtxt<'tcx>, uv: UnevaluatedConst<'tcx>, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_value( tcx: TyCtxt<'tcx>, val: ValTree<'tcx>, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_expr( tcx: TyCtxt<'tcx>, expr: Expr<'tcx>, ty: Ty<'tcx> ) -> Const<'tcx>
pub fn new_error( tcx: TyCtxt<'tcx>, e: ErrorGuaranteed, ty: Ty<'tcx> ) -> Const<'tcx>
sourcepub fn new_misc_error(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Const<'tcx>
pub fn new_misc_error(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Const<'tcx>
Like Ty::new_error but for constants.
sourcepub fn new_error_with_message<S: Into<MultiSpan>>(
tcx: TyCtxt<'tcx>,
ty: Ty<'tcx>,
span: S,
msg: &'static str
) -> Const<'tcx>
pub fn new_error_with_message<S: Into<MultiSpan>>( tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, span: S, msg: &'static str ) -> Const<'tcx>
Like Ty::new_error_with_message but for constants.
sourcepub fn from_anon_const(tcx: TyCtxt<'tcx>, def: LocalDefId) -> Self
pub fn from_anon_const(tcx: TyCtxt<'tcx>, def: LocalDefId) -> Self
Literals and const generic parameters are eagerly converted to a constant, everything else
becomes Unevaluated
.
fn try_from_lit_or_param( tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, expr: &'tcx Expr<'tcx> ) -> Option<Self>
sourcepub fn from_bits(
tcx: TyCtxt<'tcx>,
bits: u128,
ty: ParamEnvAnd<'tcx, Ty<'tcx>>
) -> Self
pub fn from_bits( tcx: TyCtxt<'tcx>, bits: u128, ty: ParamEnvAnd<'tcx, Ty<'tcx>> ) -> Self
Creates a constant with the given integer value and interns it.
sourcepub fn zero_sized(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Self
pub fn zero_sized(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Self
Creates an interned zst constant.
sourcepub fn from_target_usize(tcx: TyCtxt<'tcx>, n: u64) -> Self
pub fn from_target_usize(tcx: TyCtxt<'tcx>, n: u64) -> Self
Creates an interned usize constant.
sourcepub fn eval(
self,
tcx: TyCtxt<'tcx>,
param_env: ParamEnv<'tcx>,
span: Option<Span>
) -> Result<ValTree<'tcx>, ErrorHandled>
pub fn eval( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>, span: Option<Span> ) -> Result<ValTree<'tcx>, ErrorHandled>
Returns the evaluated constant
sourcepub fn normalize(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> Self
pub fn normalize(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> Self
Normalizes the constant to a value or an error if possible.
pub fn try_eval_scalar( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<Scalar>
sourcepub fn try_eval_scalar_int(
self,
tcx: TyCtxt<'tcx>,
param_env: ParamEnv<'tcx>
) -> Option<ScalarInt>
pub fn try_eval_scalar_int( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<ScalarInt>
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).
sourcepub fn try_eval_bits(
self,
tcx: TyCtxt<'tcx>,
param_env: ParamEnv<'tcx>
) -> Option<u128>
pub fn try_eval_bits( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'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).
sourcepub fn eval_bits(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> u128
pub fn eval_bits(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> u128
Panics if the value cannot be evaluated or doesn’t contain a valid integer of the given type.
pub fn try_eval_target_usize( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<u64>
pub fn try_eval_bool( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<bool>
sourcepub fn eval_target_usize(
self,
tcx: TyCtxt<'tcx>,
param_env: ParamEnv<'tcx>
) -> u64
pub fn eval_target_usize( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> u64
Panics if the value cannot be evaluated or doesn’t contain a valid usize
.
sourcepub fn to_valtree(self) -> ValTree<'tcx>
pub fn to_valtree(self) -> ValTree<'tcx>
Panics if self.kind != ty::ConstKind::Value
sourcepub fn try_to_valtree(self) -> Option<ValTree<'tcx>>
pub fn try_to_valtree(self) -> Option<ValTree<'tcx>>
Attempts to convert to a ValTree
pub fn try_to_scalar(self) -> Option<Scalar<AllocId>>
pub fn try_to_target_usize(self, tcx: TyCtxt<'tcx>) -> Option<u64>
pub fn is_ct_infer(self) -> bool
Trait Implementations§
source§impl<'tcx> DebugWithInfcx<TyCtxt<'tcx>> for Const<'tcx>
impl<'tcx> DebugWithInfcx<TyCtxt<'tcx>> for Const<'tcx>
fn fmt<InfCtx: InferCtxtLike<TyCtxt<'tcx>>>( this: OptWithInfcx<'_, TyCtxt<'tcx>, InfCtx, &Self>, f: &mut Formatter<'_> ) -> Result
source§impl<'tcx> From<Const<'tcx>> for GenericArg<'tcx>
impl<'tcx> From<Const<'tcx>> for GenericArg<'tcx>
source§fn from(c: Const<'tcx>) -> GenericArg<'tcx>
fn from(c: Const<'tcx>) -> GenericArg<'tcx>
source§impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for Const<'tcx>
impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for Const<'tcx>
fn hash_stable( &self, __hcx: &mut StableHashingContext<'__ctx>, __hasher: &mut StableHasher )
source§impl<'tcx> Key for Const<'tcx>
impl<'tcx> Key for Const<'tcx>
type CacheSelector = DefaultCacheSelector<Const<'tcx>>
source§fn default_span(&self, _: TyCtxt<'_>) -> Span
fn default_span(&self, _: TyCtxt<'_>) -> Span
self
, what span should we use?source§fn key_as_def_id(&self) -> Option<DefId>
fn key_as_def_id(&self) -> Option<DefId>
fn ty_adt_id(&self) -> Option<DefId>
source§impl<'tcx> Ord for Const<'tcx>
impl<'tcx> Ord for Const<'tcx>
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl<'tcx> PartialEq<Const<'tcx>> for Const<'tcx>
impl<'tcx> PartialEq<Const<'tcx>> for Const<'tcx>
source§impl<'tcx> PartialOrd<Const<'tcx>> for Const<'tcx>
impl<'tcx> PartialOrd<Const<'tcx>> for Const<'tcx>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'tcx> Relate<'tcx> for Const<'tcx>
impl<'tcx> Relate<'tcx> for Const<'tcx>
fn relate<R: TypeRelation<'tcx>>( relation: &mut R, a: Const<'tcx>, b: Const<'tcx> ) -> RelateResult<'tcx, Const<'tcx>>
source§impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for Const<'tcx>
impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for Const<'tcx>
source§fn try_fold_with<F: FallibleTypeFolder<TyCtxt<'tcx>>>(
self,
folder: &mut F
) -> Result<Self, F::Error>
fn try_fold_with<F: FallibleTypeFolder<TyCtxt<'tcx>>>( self, folder: &mut F ) -> Result<Self, F::Error>
source§fn fold_with<F>(self, folder: &mut F) -> Selfwhere
F: TypeFolder<I>,
fn fold_with<F>(self, folder: &mut F) -> Selfwhere F: TypeFolder<I>,
try_fold_with
for use with infallible
folders. Do not override this method, to ensure coherence with
try_fold_with
.source§impl<'tcx> TypeSuperFoldable<TyCtxt<'tcx>> for Const<'tcx>
impl<'tcx> TypeSuperFoldable<TyCtxt<'tcx>> for Const<'tcx>
source§fn try_super_fold_with<F: FallibleTypeFolder<TyCtxt<'tcx>>>(
self,
folder: &mut F
) -> Result<Self, F::Error>
fn try_super_fold_with<F: FallibleTypeFolder<TyCtxt<'tcx>>>( self, folder: &mut F ) -> Result<Self, F::Error>
TypeFolder
methods, when a non-custom traversal
is desired for the value of the type of interest passed to that method.
For example, in MyFolder::try_fold_ty(ty)
, it is valid to call
ty.try_super_fold_with(self)
, but any other folding should be done
with xyz.try_fold_with(self)
.source§fn super_fold_with<F>(self, folder: &mut F) -> Selfwhere
F: TypeFolder<I>,
fn super_fold_with<F>(self, folder: &mut F) -> Selfwhere F: TypeFolder<I>,
try_super_fold_with
for use with
infallible folders. Do not override this method, to ensure coherence
with try_super_fold_with
.source§impl<'tcx> TypeSuperVisitable<TyCtxt<'tcx>> for Const<'tcx>
impl<'tcx> TypeSuperVisitable<TyCtxt<'tcx>> for Const<'tcx>
source§fn super_visit_with<V: TypeVisitor<TyCtxt<'tcx>>>(
&self,
visitor: &mut V
) -> ControlFlow<V::BreakTy>
fn super_visit_with<V: TypeVisitor<TyCtxt<'tcx>>>( &self, visitor: &mut V ) -> ControlFlow<V::BreakTy>
TypeVisitor
methods, when a non-custom
traversal is desired for the value of the type of interest passed to
that method. For example, in MyVisitor::visit_ty(ty)
, it is valid to
call ty.super_visit_with(self)
, but any other visiting should be done
with xyz.visit_with(self)
.source§impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for Const<'tcx>
impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for Const<'tcx>
source§fn visit_with<V: TypeVisitor<TyCtxt<'tcx>>>(
&self,
visitor: &mut V
) -> ControlFlow<V::BreakTy>
fn visit_with<V: TypeVisitor<TyCtxt<'tcx>>>( &self, visitor: &mut V ) -> ControlFlow<V::BreakTy>
impl<'tcx> Copy for Const<'tcx>
impl<'tcx> Eq for Const<'tcx>
impl<'tcx> StructuralEq for Const<'tcx>
impl<'tcx> StructuralPartialEq for Const<'tcx>
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§
source§impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere T: Copy,
fn allocate_on<'a>(self, arena: &'a Arena<'tcx>) -> &'a mut T
fn allocate_from_iter<'a>( arena: &'a Arena<'tcx>, iter: impl IntoIterator<Item = T> ) -> &'a mut [T]
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T, R> CollectAndApply<T, R> for T
impl<T, R> CollectAndApply<T, R> for T
source§impl<Tcx, T> DepNodeParams<Tcx> for Twhere
Tcx: DepContext,
T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
impl<Tcx, T> DepNodeParams<Tcx> for Twhere Tcx: DepContext, T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
default fn fingerprint_style() -> FingerprintStyle
source§default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint
default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint
default fn to_debug_str(&self, _: Tcx) -> String
source§default fn recover(_: Tcx, _: &DepNode) -> Option<T>
default fn recover(_: Tcx, _: &DepNode) -> Option<T>
DepNode
,
something which is needed when forcing DepNode
s during red-green
evaluation. The query system will only call this method if
fingerprint_style()
is not FingerprintStyle::Opaque
.
It is always valid to return None
here, in which case incremental
compilation will treat the query as having changed instead of forcing it.source§impl<P> IntoQueryParam<P> for P
impl<P> IntoQueryParam<P> for P
fn into_query_param(self) -> P
source§impl<'tcx, T> IsSuggestable<'tcx> for Twhere
T: TypeVisitable<TyCtxt<'tcx>> + TypeFoldable<TyCtxt<'tcx>>,
impl<'tcx, T> IsSuggestable<'tcx> for Twhere T: TypeVisitable<TyCtxt<'tcx>> + TypeFoldable<TyCtxt<'tcx>>,
source§impl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
source§impl<'tcx, T> ToPredicate<'tcx, T> for T
impl<'tcx, T> ToPredicate<'tcx, T> for T
fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> T
source§impl<'tcx, T> TypeVisitableExt<'tcx> for Twhere
T: TypeVisitable<TyCtxt<'tcx>>,
impl<'tcx, T> TypeVisitableExt<'tcx> for Twhere T: TypeVisitable<TyCtxt<'tcx>>,
source§fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool
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.source§fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
true
if this type has any regions that escape binder
(and
hence are not bound by it).source§fn has_escaping_bound_vars(&self) -> bool
fn has_escaping_bound_vars(&self) -> bool
true
if this type has regions that are not a part of the type.
For example, for<'a> fn(&'a i32)
return false
, while fn(&'a i32)
would return true
. The latter can occur when traversing through the
former. Read morefn has_type_flags(&self, flags: TypeFlags) -> bool
fn has_projections(&self) -> bool
fn has_inherent_projections(&self) -> bool
fn has_opaque_types(&self) -> bool
fn has_generators(&self) -> bool
fn references_error(&self) -> bool
fn error_reported(&self) -> Result<(), ErrorGuaranteed>
fn has_non_region_param(&self) -> bool
fn has_infer_regions(&self) -> bool
fn has_infer_types(&self) -> bool
fn has_non_region_infer(&self) -> bool
fn has_infer(&self) -> bool
fn has_placeholders(&self) -> bool
fn has_non_region_placeholders(&self) -> bool
fn has_param(&self) -> bool
source§fn has_free_regions(&self) -> bool
fn has_free_regions(&self) -> bool
fn has_erased_regions(&self) -> bool
source§fn has_erasable_regions(&self) -> bool
fn has_erasable_regions(&self) -> bool
source§fn is_global(&self) -> bool
fn is_global(&self) -> bool
source§fn has_late_bound_regions(&self) -> bool
fn has_late_bound_regions(&self) -> bool
source§fn has_non_region_late_bound(&self) -> bool
fn has_non_region_late_bound(&self) -> bool
source§fn has_late_bound_vars(&self) -> bool
fn has_late_bound_vars(&self) -> bool
source§fn still_further_specializable(&self) -> bool
fn still_further_specializable(&self) -> bool
impl
specialization.source§impl<Tcx, T> Value<Tcx> for Twhere
Tcx: DepContext,
impl<Tcx, T> Value<Tcx> for Twhere Tcx: DepContext,
default fn from_cycle_error( tcx: Tcx, cycle: &[QueryInfo], _guar: ErrorGuaranteed ) -> T
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: 8 bytes