Trait BatchReader 

pub trait BatchReader: LayoutExt + Sized {
    type Cursor: Cursor<Storage = Self> + WithLayout<Layout = Self::Layout> + for<'a> LayoutExt<Key<'a> = Self::Key<'a>, KeyOwn = Self::KeyOwn, Val<'a> = Self::Val<'a>, ValOwn = Self::ValOwn, Time = Self::Time, TimeGat<'a> = Self::TimeGat<'a>, Diff = Self::Diff, DiffGat<'a> = Self::DiffGat<'a>, KeyContainer = Self::KeyContainer, ValContainer = Self::ValContainer, TimeContainer = Self::TimeContainer, DiffContainer = Self::DiffContainer>;

    // Required methods
    fn cursor(&self) -> Self::Cursor;
    fn len(&self) -> usize;
    fn description(&self) -> &Description<Self::Time>;

    // Provided methods
    fn is_empty(&self) -> bool { ... }
    fn lower(&self) -> &Antichain<Self::Time> { ... }
    fn upper(&self) -> &Antichain<Self::Time> { ... }
}

A batch of updates whose contents may be read.

This is a restricted interface to batches of updates, which support the reading of the batch’s contents, but do not expose ways to construct the batches. This trait is appropriate for views of the batch, and is especially useful for views derived from other sources in ways that prevent the construction of batches from the type of data in the view (for example, filtered views, or views with extended time coordinates).

Required Associated Types

type Cursor: Cursor<Storage = Self> + WithLayout<Layout = Self::Layout> + for<'a> LayoutExt<Key<'a> = Self::Key<'a>, KeyOwn = Self::KeyOwn, Val<'a> = Self::Val<'a>, ValOwn = Self::ValOwn, Time = Self::Time, TimeGat<'a> = Self::TimeGat<'a>, Diff = Self::Diff, DiffGat<'a> = Self::DiffGat<'a>, KeyContainer = Self::KeyContainer, ValContainer = Self::ValContainer, TimeContainer = Self::TimeContainer, DiffContainer = Self::DiffContainer>

The type used to enumerate the batch’s contents.

Required Methods

fn cursor(&self) -> Self::Cursor

Acquires a cursor to the batch’s contents.

fn len(&self) -> usize

The number of updates in the batch.

fn description(&self) -> &Description<Self::Time>

Describes the times of the updates in the batch.

Provided Methods

fn is_empty(&self) -> bool

True if the batch is empty.

fn lower(&self) -> &Antichain<Self::Time>

All times in the batch are greater or equal to an element of lower.

fn upper(&self) -> &Antichain<Self::Time>

All times in the batch are not greater or equal to any element of upper.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<B: BatchReader> BatchReader for Rc<B>

type Cursor = RcBatchCursor<<B as BatchReader>::Cursor>

The type used to enumerate the batch’s contents.

fn cursor(&self) -> Self::Cursor

Acquires a cursor to the batch’s contents.

fn len(&self) -> usize

The number of updates in the batch.

fn description(&self) -> &Description<Self::Time>

Describes the times of the updates in the batch.

Implementors

impl<B, F> BatchReader for BatchFilter<B, F>

where B: BatchReader, F: FnMut(B::Key<'_>, B::Val<'_>) -> bool + Clone + 'static,

type Cursor = BatchCursorFilter<<B as BatchReader>::Cursor, F>

impl<B, F> BatchReader for BatchFreeze<B, F>

where B: BatchReader, F: Fn(B::TimeGat<'_>) -> Option<B::Time>,

type Cursor = BatchCursorFreeze<<B as BatchReader>::Cursor, F>

impl<B, TInner> BatchReader for differential_dataflow::trace::wrappers::enter::BatchEnter<B, TInner>

where B: BatchReader, TInner: Refines<B::Time> + Lattice,

type Cursor = BatchCursorEnter<<B as BatchReader>::Cursor, TInner>

impl<B, TInner, F> BatchReader for differential_dataflow::trace::wrappers::enter_at::BatchEnter<B, TInner, F>

where B: BatchReader, TInner: Refines<B::Time> + Lattice, F: FnMut(B::Key<'_>, <B::Cursor as LayoutExt>::Val<'_>, B::TimeGat<'_>) -> TInner + Clone,

type Cursor = BatchCursorEnter<<B as BatchReader>::Cursor, TInner, F>

impl<B: BatchReader> BatchReader for BatchFrontier<B>

type Cursor = BatchCursorFrontier<<B as BatchReader>::Cursor>

impl<L: Layout> BatchReader for OrdValBatch<L>

type Cursor = OrdValCursor<L>

impl<L: for<'a> Layout<ValContainer: BatchContainer<ReadItem<'a> = &'a ()>>> BatchReader for OrdKeyBatch<L>

type Cursor = OrdKeyCursor<L>