Struct rustc_middle::ty::TyS

source ·
pub(crate) struct TyS<'tcx> {
    kind: TyKind<'tcx>,
    flags: TypeFlags,
    outer_exclusive_binder: DebruijnIndex,
}
Expand description

Represents a type.

IMPORTANT:

  • This is a very “dumb” struct (with no derives and no impls).
  • Values of this type are always interned and thus unique, and are stored as an Interned<TyS>.
  • Ty (which contains a reference to a Interned<TyS>) or Interned<TyS> should be used everywhere instead of TyS. In particular, Ty has most of the relevant methods.

Fields§

§kind: TyKind<'tcx>

This field shouldn’t be used directly and may be removed in the future. Use Ty::kind() instead.

§flags: TypeFlags

This field provides fast access to information that is also contained in kind.

This field shouldn’t be used directly and may be removed in the future. Use Ty::flags() instead.

§outer_exclusive_binder: DebruijnIndex

This field provides fast access to information that is also contained in kind.

This is a kind of confusing thing: it stores the smallest binder such that

(a) the binder itself captures nothing but (b) all the late-bound things within the type are captured by some sub-binder.

So, for a type without any late-bound things, like u32, this will be innermost, because that is the innermost binder that captures nothing. But for a type &'D u32, where 'D is a late-bound region with De Bruijn index D, this would be D + 1 – the binder itself does not capture D, but D is captured by an inner binder.

We call this concept an “exclusive” binder D because all De Bruijn indices within the type are contained within 0..D (exclusive).

Trait Implementations§

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

Returns the argument unchanged.

Calls U::from(self).

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

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: 40 bytes