Enum rustc_trait_selection::infer::canonical::CanonicalVarKind

pub enum CanonicalVarKind<I>
where
    I: Interner,
{
    Ty(CanonicalTyVarKind),
    PlaceholderTy(<I as Interner>::PlaceholderTy),
    Region(UniverseIndex),
    PlaceholderRegion(<I as Interner>::PlaceholderRegion),
    Const(UniverseIndex),
    Effect,
    PlaceholderConst(<I as Interner>::PlaceholderConst),
}

Describes the “kind” of the canonical variable. This is a “kind” in the type-theory sense of the term – i.e., a “meta” type system that analyzes type-like values.

Variants

Ty(CanonicalTyVarKind)

Some kind of type inference variable.

PlaceholderTy(<I as Interner>::PlaceholderTy)

A “placeholder” that represents “any type”.

Region(UniverseIndex)

Region variable '?R.

PlaceholderRegion(<I as Interner>::PlaceholderRegion)

A “placeholder” that represents “any region”. Created when you are solving a goal like for<'a> T: Foo<'a> to represent the bound region 'a.

Const(UniverseIndex)

Some kind of const inference variable.

Effect

Effect variable '?E.

PlaceholderConst(<I as Interner>::PlaceholderConst)

A “placeholder” that represents “any const”.

Implementations

impl<I> CanonicalVarKind<I>

where I: Interner,

pub fn universe(self) -> UniverseIndex

pub fn with_updated_universe(self, ui: UniverseIndex) -> CanonicalVarKind<I>

Replaces the universe of this canonical variable with ui.

In case this is a float or int variable, this causes an ICE if the updated universe is not the root.

Trait Implementations

impl<I> Clone for CanonicalVarKind<I>

where I: Interner,

fn clone(&self) -> CanonicalVarKind<I>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<I> Debug for CanonicalVarKind<I>

where I: Interner,

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

Formats the value using the given formatter.

impl<I, __D> Decodable<__D> for CanonicalVarKind<I>

where I: Interner, __D: TyDecoder<I = I>, <I as Interner>::PlaceholderTy: Decodable<__D>, <I as Interner>::PlaceholderRegion: Decodable<__D>, <I as Interner>::PlaceholderConst: Decodable<__D>,

fn decode(__decoder: &mut __D) -> CanonicalVarKind<I>

impl<I, __E> Encodable<__E> for CanonicalVarKind<I>

where I: Interner, __E: TyEncoder<I = I>, <I as Interner>::PlaceholderTy: Encodable<__E>, <I as Interner>::PlaceholderRegion: Encodable<__E>, <I as Interner>::PlaceholderConst: Encodable<__E>,

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

impl<I> Hash for CanonicalVarKind<I>

where I: Interner,

fn hash<__H>(&self, __state: &mut __H)

where __H: Hasher,

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<I, __CTX> HashStable<__CTX> for CanonicalVarKind<I>

where I: Interner, <I as Interner>::PlaceholderTy: HashStable<__CTX>, <I as Interner>::PlaceholderRegion: HashStable<__CTX>, <I as Interner>::PlaceholderConst: HashStable<__CTX>,

fn hash_stable( &self, __hcx: &mut __CTX, __hasher: &mut StableHasher<SipHasher128>, )

impl<I> PartialEq for CanonicalVarKind<I>

where I: Interner,

fn eq(&self, __other: &CanonicalVarKind<I>) -> bool

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<I> TypeFoldable<I> for CanonicalVarKind<I>

where I: Interner, <I as Interner>::PlaceholderTy: TypeFoldable<I>, <I as Interner>::PlaceholderRegion: TypeFoldable<I>, <I as Interner>::PlaceholderConst: TypeFoldable<I>,

fn try_fold_with<__F>( self, __folder: &mut __F, ) -> Result<CanonicalVarKind<I>, <__F as FallibleTypeFolder<I>>::Error>

where __F: FallibleTypeFolder<I>,

The entry point for folding. To fold a value t with a folder f call: t.try_fold_with(f).

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

where F: TypeFolder<I>,

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<I> TypeVisitable<I> for CanonicalVarKind<I>

where I: Interner, <I as Interner>::PlaceholderTy: TypeVisitable<I>, <I as Interner>::PlaceholderRegion: TypeVisitable<I>, <I as Interner>::PlaceholderConst: TypeVisitable<I>,

fn visit_with<__V>( &self, __visitor: &mut __V, ) -> <__V as TypeVisitor<I>>::Result

where __V: TypeVisitor<I>,

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

impl<I> Copy for CanonicalVarKind<I>

where I: Interner,

impl<I> Eq for CanonicalVarKind<I>

where I: Interner,

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.