Struct ExistentialTraitRef

pub struct ExistentialTraitRef<I: Interner> {
    pub def_id: I::DefId,
    pub args: I::GenericArgs,
    _use_existential_trait_ref_new_instead: (),
}

An existential reference to a trait, where Self is erased. For example, the trait object Trait<'a, 'b, X, Y> is:

exists T. T: Trait<'a, 'b, X, Y>

The generic parameters don’t include the erased Self, only trait type and lifetime parameters ([X, Y] and ['a, 'b] above).

Fields

def_id: I::DefId

args: I::GenericArgs

_use_existential_trait_ref_new_instead: ()

This field exists to prevent the creation of ExistentialTraitRef without calling ExistentialTraitRef::new_from_args.

Implementations

impl<I: Interner> ExistentialTraitRef<I>

pub fn new_from_args( interner: I, trait_def_id: I::DefId, args: I::GenericArgs, ) -> Self

pub fn new( interner: I, trait_def_id: I::DefId, args: impl IntoIterator<Item: Into<I::GenericArg>>, ) -> Self

pub fn erase_self_ty( interner: I, trait_ref: TraitRef<I>, ) -> ExistentialTraitRef<I>

pub fn with_self_ty(self, interner: I, self_ty: I::Ty) -> TraitRef<I>

Object types don’t have a self type specified. Therefore, when we convert the principal trait-ref into a normal trait-ref, you must give some self type. A common choice is mk_err() or some placeholder type.

Trait Implementations

impl<I> Clone for ExistentialTraitRef<I>

where I: Interner,

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<I: Interner> Debug for ExistentialTraitRef<I>

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

Formats the value using the given formatter.

impl<I: Interner, __D: TyDecoder<I = I>> Decodable<__D> for ExistentialTraitRef<I>

where I::DefId: Decodable<__D>, I::GenericArgs: Decodable<__D>,

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

impl<I: Interner> Display for ExistentialTraitRef<I>

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

Formats the value using the given formatter.

impl<I: Interner, __E: TyEncoder<I = I>> Encodable<__E> for ExistentialTraitRef<I>

where I::DefId: Encodable<__E>, I::GenericArgs: Encodable<__E>,

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

impl<I> Hash for ExistentialTraitRef<I>

where I: Interner,

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<I: Interner, __CTX> HashStable<__CTX> for ExistentialTraitRef<I>

where I::DefId: HashStable<__CTX>, I::GenericArgs: HashStable<__CTX>,

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

impl<I, J> Lift<J> for ExistentialTraitRef<I>

where I: Interner, J: Interner, I::DefId: Lift<J, Lifted = J::DefId>, I::GenericArgs: Lift<J, Lifted = J::GenericArgs>, (): Lift<J, Lifted = ()>,

type Lifted = ExistentialTraitRef<J>

fn lift_to_interner(self, interner: J) -> Option<Self::Lifted>

impl<I> PartialEq for ExistentialTraitRef<I>

where I: Interner,

fn eq(&self, __other: &Self) -> 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: Interner> Relate<I> for ExistentialTraitRef<I>

fn relate<R: TypeRelation<I>>( relation: &mut R, a: ExistentialTraitRef<I>, b: ExistentialTraitRef<I>, ) -> RelateResult<I, ExistentialTraitRef<I>>

impl<I> TypeFoldable<I> for ExistentialTraitRef<I>

where I: Interner, I::DefId: TypeFoldable<I>, I::GenericArgs: TypeFoldable<I>,

fn try_fold_with<__F: FallibleTypeFolder<I>>( self, __folder: &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<I>>(self, folder: &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<I> TypeVisitable<I> for ExistentialTraitRef<I>

where I: Interner, I::DefId: TypeVisitable<I>, I::GenericArgs: TypeVisitable<I>,

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

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

impl<I> Copy for ExistentialTraitRef<I>

where I: Interner,

impl<I> Eq for ExistentialTraitRef<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.