Struct rustc_middle::ty::VariantDef

source ·
pub struct VariantDef {
    pub def_id: DefId,
    pub ctor: Option<(CtorKind, DefId)>,
    pub name: Symbol,
    pub discr: VariantDiscr,
    pub fields: IndexVec<FieldIdx, FieldDef>,
    flags: VariantFlags,
}
Expand description

Definition of a variant – a struct’s fields or an enum variant.

Fields§

§def_id: DefId

DefId that identifies the variant itself. If this variant belongs to a struct or union, then this is a copy of its DefId.

§ctor: Option<(CtorKind, DefId)>

DefId that identifies the variant’s constructor. If this variant is a struct variant, then this is None.

§name: Symbol

Variant or struct name.

§discr: VariantDiscr

Discriminant of this variant.

§fields: IndexVec<FieldIdx, FieldDef>

Fields of this variant.

§flags: VariantFlags

Flags of the variant (e.g. is field list non-exhaustive)?

Implementations§

source§

impl<'tcx> VariantDef

source

pub fn inhabited_predicate( &self, tcx: TyCtxt<'tcx>, adt: AdtDef<'_> ) -> InhabitedPredicate<'tcx>

Calculates the forest of DefIds from which this variant is visibly uninhabited.

source§

impl VariantDef

source

pub fn new( name: Symbol, variant_did: Option<DefId>, ctor: Option<(CtorKind, DefId)>, discr: VariantDiscr, fields: IndexVec<FieldIdx, FieldDef>, adt_kind: AdtKind, parent_did: DefId, recovered: bool, is_field_list_non_exhaustive: bool ) -> Self

Creates a new VariantDef.

variant_did is the DefId that identifies the enum variant (if this VariantDef represents an enum variant).

ctor_did is the DefId that identifies the constructor of unit or tuple-variants/structs. If this is a struct-variant then this should be None.

parent_did is the DefId of the AdtDef representing the enum or struct that owns this variant. It is used for checking if a struct has #[non_exhaustive] w/out having to go through the redirect of checking the ctor’s attributes - but compiling a small crate requires loading the AdtDefs for all the structs in the universe (e.g., coherence for any built-in trait), and we do not want to load attributes twice.

If someone speeds up attribute loading to not be a performance concern, they can remove this hack and use the constructor DefId everywhere.

source

pub fn is_field_list_non_exhaustive(&self) -> bool

Is this field list non-exhaustive?

source

pub fn is_recovered(&self) -> bool

Was this variant obtained as part of recovering from a syntactic error?

source

pub fn ident(&self, tcx: TyCtxt<'_>) -> Ident

Computes the Ident of this variant by looking up the Span

source

pub fn ctor_kind(&self) -> Option<CtorKind>

source

pub fn ctor_def_id(&self) -> Option<DefId>

source

pub fn single_field(&self) -> &FieldDef

Returns the one field in this variant.

panic!s if there are no fields or multiple fields.

source

pub fn tail_opt(&self) -> Option<&FieldDef>

Returns the last field in this variant, if present.

source

pub fn tail(&self) -> &FieldDef

Returns the last field in this variant.

Panics

Panics, if the variant has no fields.

Trait Implementations§

source§

impl Debug for VariantDef

source§

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

Formats the value using the given formatter. Read more
source§

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

source§

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

source§

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

source§

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

source§

impl Hash for VariantDef

source§

fn hash<H: Hasher>(&self, s: &mut H)

Feeds this value into the given Hasher. Read more
1.3.0 · source§

fn hash_slice<H>(data: &[Self], state: &mut H)where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher. Read more
source§

impl<'__ctx> HashStable<StableHashingContext<'__ctx>> for VariantDef

source§

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

source§

impl PartialEq<VariantDef> for VariantDef

source§

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.
1.0.0 · source§

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.
source§

impl Eq for VariantDef

Auto Trait Implementations§

Blanket Implementations§

source§

impl<T> Aligned for T

source§

const ALIGN: Alignment = _

Alignment of Self.
source§

impl<T> Any for Twhere T: 'static + ?Sized,

source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
source§

impl<T> Borrow<T> for Twhere T: ?Sized,

source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
source§

impl<T> BorrowMut<T> for Twhere T: ?Sized,

source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
source§

impl<T, R> CollectAndApply<T, R> for T

source§

fn collect_and_apply<I, F>(iter: I, f: F) -> Rwhere I: Iterator<Item = T>, F: FnOnce(&[T]) -> R,

Equivalent to f(&iter.collect::<Vec<_>>()).

§

type Output = R

source§

impl<Tcx, T> DepNodeParams<Tcx> for Twhere Tcx: DepContext, T: for<'a> HashStable<StableHashingContext<'a>> + Debug,

source§

default fn fingerprint_style() -> FingerprintStyle

source§

default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint

This method turns the parameters of a DepNodeConstructor into an opaque Fingerprint to be used in DepNode. Not all DepNodeParams support being turned into a Fingerprint (they don’t need to if the corresponding DepNode is anonymous).
source§

default fn to_debug_str(&self, _: Tcx) -> String

source§

default fn recover(_: Tcx, _: &DepNode) -> Option<T>

This method tries to recover the query key from the given DepNode, something which is needed when forcing DepNodes 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<T> From<T> for T

source§

fn from(t: T) -> T

Returns the argument unchanged.

source§

impl<T, U> Into<U> for Twhere U: From<T>,

source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

source§

impl<P> IntoQueryParam<P> for P

source§

impl<T> MaybeResult<T> for T

§

type Error = !

source§

fn from(_: Result<T, <T as MaybeResult<T>>::Error>) -> T

source§

fn to_result(self) -> Result<T, <T as MaybeResult<T>>::Error>

source§

impl<'tcx, T> ToPredicate<'tcx, T> for T

source§

fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> T

source§

impl<T, U> TryFrom<U> for Twhere U: Into<T>,

§

type Error = Infallible

The type returned in the event of a conversion error.
source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
source§

impl<T, U> TryInto<U> for Twhere U: TryFrom<T>,

§

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
source§

impl<Tcx, T> Value<Tcx> for Twhere Tcx: DepContext,

source§

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: 64 bytes