pub enum TyKind<'tcx> {
Show 27 variants Bool, Char, Int(IntTy), Uint(UintTy), Float(FloatTy), Adt(&'tcx AdtDef, SubstsRef<'tcx>), Foreign(DefId), Str, Array(Ty<'tcx>, &'tcx Const<'tcx>), Slice(Ty<'tcx>), RawPtr(TypeAndMut<'tcx>), Ref(Region<'tcx>, Ty<'tcx>, Mutability), FnDef(DefId, SubstsRef<'tcx>), FnPtr(PolyFnSig<'tcx>), Dynamic(&'tcx List<Binder<'tcx, ExistentialPredicate<'tcx>>>, Region<'tcx>), Closure(DefId, SubstsRef<'tcx>), Generator(DefId, SubstsRef<'tcx>, Movability), GeneratorWitness(Binder<'tcx, &'tcx List<Ty<'tcx>>>), Never, Tuple(SubstsRef<'tcx>), Projection(ProjectionTy<'tcx>), Opaque(DefId, SubstsRef<'tcx>), Param(ParamTy), Bound(DebruijnIndex, BoundTy), Placeholder(PlaceholderType), Infer(InferTy), Error(DelaySpanBugEmitted),
}
Expand description

Defines the kinds of types.

N.B., if you change this, you’ll probably want to change the corresponding AST structure in rustc_ast/src/ast.rs as well.

Variants

Bool

The primitive boolean type. Written as bool.

Char

The primitive character type; holds a Unicode scalar value (a non-surrogate code point). Written as char.

Int(IntTy)

A primitive signed integer type. For example, i32.

Uint(UintTy)

A primitive unsigned integer type. For example, u32.

Float(FloatTy)

A primitive floating-point type. For example, f64.

Adt(&'tcx AdtDef, SubstsRef<'tcx>)

Algebraic data types (ADT). For example: structures, enumerations and unions.

InternalSubsts here, possibly against intuition, may contain Params. That is, even after substitution it is possible that there are type variables. This happens when the Adt corresponds to an ADT definition and not a concrete use of it.

Foreign(DefId)

An unsized FFI type that is opaque to Rust. Written as extern type T.

Str

The pointee of a string slice. Written as str.

Array(Ty<'tcx>, &'tcx Const<'tcx>)

An array with the given length. Written as [T; n].

Slice(Ty<'tcx>)

The pointee of an array slice. Written as [T].

RawPtr(TypeAndMut<'tcx>)

A raw pointer. Written as *mut T or *const T

Ref(Region<'tcx>, Ty<'tcx>, Mutability)

A reference; a pointer with an associated lifetime. Written as &'a mut T or &'a T.

FnDef(DefId, SubstsRef<'tcx>)

The anonymous type of a function declaration/definition. Each function has a unique type, which is output (for a function named foo returning an i32) as fn() -> i32 {foo}.

For example the type of bar here:

fn foo() -> i32 { 1 }
let bar = foo; // bar: fn() -> i32 {foo}

FnPtr(PolyFnSig<'tcx>)

A pointer to a function. Written as fn() -> i32.

For example the type of bar here:

fn foo() -> i32 { 1 }
let bar: fn() -> i32 = foo;

Dynamic(&'tcx List<Binder<'tcx, ExistentialPredicate<'tcx>>>, Region<'tcx>)

A trait object. Written as dyn for<'b> Trait<'b, Assoc = u32> + Send + 'a.

Closure(DefId, SubstsRef<'tcx>)

The anonymous type of a closure. Used to represent the type of |a| a.

Generator(DefId, SubstsRef<'tcx>, Movability)

The anonymous type of a generator. Used to represent the type of |a| yield a.

GeneratorWitness(Binder<'tcx, &'tcx List<Ty<'tcx>>>)

A type representing the types stored inside a generator. This should only appear in GeneratorInteriors.

Never

The never type !.

Tuple(SubstsRef<'tcx>)

A tuple type. For example, (i32, bool). Use TyS::tuple_fields to iterate over the field types.

Projection(ProjectionTy<'tcx>)

The projection of an associated type. For example, <T as Trait<..>>::N.

Opaque(DefId, SubstsRef<'tcx>)

Opaque (impl Trait) type found in a return type. The DefId comes either from

  • the impl Trait ast::Ty node,
  • or the type Foo = impl Trait declaration The substitutions are for the generics of the function in question. After typeck, the concrete type can be found in the types map.

Param(ParamTy)

A type parameter; for example, T in fn f<T>(x: T) {}.

Bound(DebruijnIndex, BoundTy)

Bound type variable, used only when preparing a trait query.

Placeholder(PlaceholderType)

A placeholder type - universally quantified higher-ranked type.

Infer(InferTy)

A type variable used during type checking.

Error(DelaySpanBugEmitted)

A placeholder for a type which could not be computed; this is propagated to avoid useless error messages.

Implementations

Get the article (“a” or “an”) to use with this type.

Trait Implementations

Immutably borrows from an owned value. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Feeds this value into the given Hasher. Read more

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

This method returns an Ordering between self and other. Read more

Compares and returns the maximum of two values. Read more

Compares and returns the minimum of two values. Read more

Restrict a value to a certain interval. Read more

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

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). Read more

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. Read more

Performs the conversion.

Performs the conversion.

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

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: 32 bytes

Size for each variant:

  • Bool: 0 bytes
  • Char: 0 bytes
  • Int: 1 byte
  • Uint: 1 byte
  • Float: 1 byte
  • Adt: 23 bytes
  • Foreign: 11 bytes
  • Str: 0 bytes
  • Array: 23 bytes
  • Slice: 15 bytes
  • RawPtr: 23 bytes
  • Ref: 23 bytes
  • FnDef: 23 bytes
  • FnPtr: 31 bytes
  • Dynamic: 23 bytes
  • Closure: 23 bytes
  • Generator: 23 bytes
  • GeneratorWitness: 23 bytes
  • Never: 0 bytes
  • Tuple: 15 bytes
  • Projection: 23 bytes
  • Opaque: 23 bytes
  • Param: 11 bytes
  • Bound: 15 bytes
  • Placeholder: 11 bytes
  • Infer: 11 bytes
  • Error: 0 bytes