pub struct UserTypeProjection {
    pub base: UserTypeAnnotationIndex,
    pub projs: Vec<ProjectionKind>,
}
Expand description

Encodes the effect of a user-supplied type annotation on the subcomponents of a pattern. The effect is determined by applying the given list of projections to some underlying base type. Often, the projection element list projs is empty, in which case this directly encodes a type in base. But in the case of complex patterns with subpatterns and bindings, we want to apply only a part of the type to a variable, in which case the projs vector is used.

Examples:

  • let x: T = ... – here, the projs vector is empty.

  • let (x, _): T = ... – here, the projs vector would contain field[0] (aka .0), indicating that the type of s is determined by finding the type of the .0 field from T.

Fields§

§base: UserTypeAnnotationIndex§projs: Vec<ProjectionKind>

Implementations§

Trait Implementations§

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 tests for self and other values to be equal, and is used by ==.
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
The entry point for folding. To fold a value t with a folder f call: t.try_fold_with(f). Read more
A convenient alternative to try_fold_with for use with infallible folders. Do not override this method, to ensure coherence with try_fold_with.
The entry point for visiting. To visit a value t with a visitor v call: t.visit_with(v). Read more
Returns true if self has any late-bound regions that are either bound by binder or bound by some binder outside of binder. If binder is ty::INNERMOST, this indicates whether there are any late-bound regions that appear free.
Returns true if this type has any regions that escape binder (and hence are not bound by it).
Return true if this type has regions that are not a part of the type. For example, for<'a> fn(&'a i32) return false, while fn(&'a i32) would return true. The latter can occur when traversing through the former. Read more
“Free” regions in this context means that it has any region that is not (a) erased or (b) late-bound.
True if there are any un-erased free regions.
Indicates whether this value references only ‘global’ generic parameters that are the same regardless of what fn we are in. This is used for caching.
True if there are any late-bound regions
True if there are any late-bound non-region variables
True if there are any late-bound variables
Indicates whether this value still has parameters/placeholders/inference variables which could be replaced later, in a way that would change the results of impl specialization.

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).
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.

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 resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
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