Struct rustc_type_ir::predicate::AliasTerm

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

Represents the unprojected term of a projection goal.

• For a projection, this would be <Ty as Trait<...>>::N<...>.
• For an inherent projection, this would be Ty::N<...>.
• For an opaque type, there is no explicit syntax.

Fields

args: I::GenericArgs

The parameters of the associated or opaque item.

For a projection, these are the generic parameters for the trait and the GAT parameters, if there are any.

For an inherent projection, they consist of the self type and the GAT parameters, if there are any.

For RPIT the generic parameters are for the generics of the function, while for TAIT it is used for the generic parameters of the alias.

def_id: I::DefId

The DefId of the TraitItem or ImplItem for the associated type N depending on whether this is a projection or an inherent projection or the DefId of the OpaqueType item if this is an opaque.

During codegen, interner.type_of(def_id) can be used to get the type of the underlying type if the type is an opaque.

Note that if this is an associated type, this is not the DefId of the TraitRef containing this associated type, which is in interner.associated_item(def_id).container, aka. interner.parent(def_id).

_use_alias_term_new_instead: ()

This field exists to prevent the creation of AliasTerm without using AliasTerm::new_from_args.

Implementations

impl<I: Interner> AliasTerm<I>

pub fn new_from_args( interner: I, def_id: I::DefId, args: I::GenericArgs, ) -> AliasTerm<I>

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

pub fn expect_ty(self, interner: I) -> AliasTy<I>

pub fn kind(self, interner: I) -> AliasTermKind

pub fn to_term(self, interner: I) -> I::Term

impl<I: Interner> AliasTerm<I>

The following methods work only with (trait) associated type projections.

pub fn self_ty(self) -> I::Ty

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

pub fn trait_def_id(self, interner: I) -> I::DefId

pub fn trait_ref_and_own_args( self, interner: I, ) -> (TraitRef<I>, I::GenericArgsSlice)

Extracts the underlying trait reference and own args from this projection. For example, if this is a projection of <T as StreamingIterator>::Item<'a>, then this function would return a T: StreamingIterator trait reference and ['a] as the own args.

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

Extracts the underlying trait reference from this projection. For example, if this is a projection of <T as Iterator>::Item, then this function would return a T: Iterator trait reference.

WARNING: This will drop the args for generic associated types consider calling Self::trait_ref_and_own_args to get those as well.

Trait Implementations

impl<I> Clone for AliasTerm<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> Debug for AliasTerm<I>

where I: Interner,

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

Formats the value using the given formatter.

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

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

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

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

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

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

impl<I: Interner> From<AliasTy<I>> for AliasTerm<I>

fn from(ty: AliasTy<I>) -> Self

Converts to this type from the input type.

impl<I: Interner> From<UnevaluatedConst<I>> for AliasTerm<I>

fn from(ct: UnevaluatedConst<I>) -> Self

Converts to this type from the input type.

impl<I> Hash for AliasTerm<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 AliasTerm<I>

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

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

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

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

type Lifted = AliasTerm<J>

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

impl<I> PartialEq for AliasTerm<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 AliasTerm<I>

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

impl<I> TypeFoldable<I> for AliasTerm<I>

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

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

where I: Interner,

impl<I> Eq for AliasTerm<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.