Enum rustc_middle::infer::canonical::CanonicalTyVarKind

pub enum CanonicalTyVarKind {
    General(UniverseIndex),
    Int,
    Float,
}

Rust actually has more than one category of type variables; notably, the type variables we create for literals (e.g., 22 or 22.) can only be instantiated with integral/float types (e.g., usize or f32). In order to faithfully reproduce a type, we need to know what set of types a given type variable can be unified with.

Variants

General(UniverseIndex)

General type variable ?T that can be unified with arbitrary types.

Int

Integral type variable ?I (that can only be unified with integral types).

Float

Floating-point type variable ?F (that can only be unified with float types).

Trait Implementations

impl Clone for CanonicalTyVarKind

fn clone(&self) -> CanonicalTyVarKind

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for CanonicalTyVarKind

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

Formats the value using the given formatter.

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

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

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

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

impl Hash for CanonicalTyVarKind

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<'__ctx> HashStable<StableHashingContext<'__ctx>> for CanonicalTyVarKind

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

impl<'tcx> Lift<'tcx> for CanonicalTyVarKind

type Lifted = CanonicalTyVarKind

fn lift_to_tcx(self, _: TyCtxt<'tcx>) -> Option<Self>

impl PartialEq<CanonicalTyVarKind> for CanonicalTyVarKind

fn eq(&self, other: &CanonicalTyVarKind) -> 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> TypeFoldable<'tcx> for CanonicalTyVarKind

fn try_fold_with<F: FallibleTypeFolder<'tcx>>(
    self,
    _: &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: TypeFolder<'tcx>>(self, _: &mut F) -> Self

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<'tcx> for CanonicalTyVarKind

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

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

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 type has any regions that escape binder (and hence are not bound by it).

fn has_escaping_bound_vars(&self) -> bool

Return 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.

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 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 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 Copy for CanonicalTyVarKind

impl Eq for CanonicalTyVarKind

impl StructuralEq for CanonicalTyVarKind

impl StructuralPartialEq for CanonicalTyVarKind

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: 4 bytes

Size for each variant:

• General: 4 bytes
• Int: 0 bytes
• Float: 0 bytes