Struct rustc_pattern_analysis::usefulness::PlaceInfo

struct PlaceInfo<Cx: PatCx> {
    ty: Cx::Ty,
    private_uninhabited: bool,
    validity: PlaceValidity,
    is_scrutinee: bool,
}

Data about a place under investigation. Its methods contain a lot of the logic used to analyze the constructors in the matrix.

Fields

ty: Cx::Ty

The type of the place.

private_uninhabited: bool

Whether the place is a private uninhabited field. If so we skip this field during analysis so that we don’t observe its emptiness.

validity: PlaceValidity

Whether the place is known to contain valid data.

is_scrutinee: bool

Whether the place is the scrutinee itself or a subplace of it.

Implementations

impl<Cx: PatCx> PlaceInfo<Cx>

fn specialize<'a>( &'a self, cx: &'a Cx, ctor: &'a Constructor<Cx>, ) -> impl Iterator<Item = Self> + ExactSizeIterator + Captures<'a>

Given a constructor for the current place, we return one PlaceInfo for each field of the constructor.

fn split_column_ctors<'a>( &self, cx: &Cx, ctors: impl Iterator<Item = &'a Constructor<Cx>> + Clone, ) -> Result<(SmallVec<[Constructor<Cx>; 1]>, Vec<Constructor<Cx>>), Cx::Error>

where Cx: 'a,

This analyzes a column of constructors corresponding to the current place. It returns a pair (split_ctors, missing_ctors).

split_ctors is a splitted list of constructors that cover the whole type. This will be used to specialize the matrix.

missing_ctors is a list of the constructors not found in the column, for reporting purposes.

Trait Implementations

impl<Cx: PatCx> Clone for PlaceInfo<Cx>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

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.