Struct rustc_mir_build::thir::pattern::usefulness::PatStack

struct PatStack<'p, 'tcx> {
    pats: SmallVec<[&'p DeconstructedPat<'p, 'tcx>; 2]>,
}

A row of a matrix. Rows of len 1 are very common, which is why SmallVec[_; 2] works well.

Fields

pats: SmallVec<[&'p DeconstructedPat<'p, 'tcx>; 2]>

Implementations

impl<'p, 'tcx> PatStack<'p, 'tcx>

fn from_pattern(pat: &'p DeconstructedPat<'p, 'tcx>) -> Self

fn from_vec(vec: SmallVec<[&'p DeconstructedPat<'p, 'tcx>; 2]>) -> Self

fn is_empty(&self) -> bool

fn len(&self) -> usize

fn head(&self) -> &'p DeconstructedPat<'p, 'tcx>

fn iter(&self) -> impl Iterator<Item = &DeconstructedPat<'p, 'tcx>>

fn expand_or_pat<'a>(
    &'a self
) -> impl Iterator<Item = PatStack<'p, 'tcx>> + Captures<'a>

fn pop_head_constructor(
    &self,
    cx: &MatchCheckCtxt<'p, 'tcx>,
    ctor: &Constructor<'tcx>
) -> PatStack<'p, 'tcx>

This computes S(self.head().ctor(), self). See top of the file for explanations.

Structure patterns with a partial wild pattern (Foo { a: 42, .. }) have their missing fields filled with wild patterns.

This is roughly the inverse of Constructor::apply.

Trait Implementations

impl<'p, 'tcx> Clone for PatStack<'p, 'tcx>

fn clone(&self) -> PatStack<'p, 'tcx>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'p, 'tcx> Debug for PatStack<'p, 'tcx>

Pretty-printing for matrix row.

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

Formats the value using the given formatter.

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: 24 bytes