Trait BatchReader

pub trait BatchReader
where
    Self: Sized,
{
    type Key<'a>: Copy + Clone + MyTrait<'a, Owned = Self::KeyOwned>;
    type KeyOwned: Ord + Clone;
    type Val<'a>: Copy + Clone + MyTrait<'a, Owned = Self::ValOwned>;
    type ValOwned: Ord + Clone;
    type Time: Timestamp;
    type Diff;
    type Cursor: for<'a> Cursor<Storage = Self, Key<'a> = Self::Key<'a>, KeyOwned = Self::KeyOwned, Val<'a> = Self::Val<'a>, ValOwned = Self::ValOwned, Time = Self::Time, Diff = Self::Diff>;

    // 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 Key<'a>: Copy + Clone + MyTrait<'a, Owned = Self::KeyOwned>

Key by which updates are indexed.

type KeyOwned: Ord + Clone

Owned version of the above.

type Val<'a>: Copy + Clone + MyTrait<'a, Owned = Self::ValOwned>

Values associated with keys.

type ValOwned: Ord + Clone

Owned version of the above.

type Time: Timestamp

Timestamps associated with updates

type Diff

Associated update.

type Cursor: for<'a> Cursor<Storage = Self, Key<'a> = Self::Key<'a>, KeyOwned = Self::KeyOwned, Val<'a> = Self::Val<'a>, ValOwned = Self::ValOwned, Time = Self::Time, Diff = Self::Diff>

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 + Abomonation> BatchReader for Abomonated<B, Vec<u8>>

type Cursor = AbomonatedBatchCursor<<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.

type Key<'a> = <B as BatchReader>::Key<'a>

type KeyOwned = <B as BatchReader>::KeyOwned

type Val<'a> = <B as BatchReader>::Val<'a>

type ValOwned = <B as BatchReader>::ValOwned

type Time = <B as BatchReader>::Time

type Diff = <B as BatchReader>::Diff

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.

type Key<'a> = <B as BatchReader>::Key<'a>

type KeyOwned = <B as BatchReader>::KeyOwned

type Val<'a> = <B as BatchReader>::Val<'a>

type ValOwned = <B as BatchReader>::ValOwned

type Time = <B as BatchReader>::Time

type Diff = <B as BatchReader>::Diff

Implementors

impl<B> BatchReader for BatchFrontier<B>

where B: BatchReader, B::Time: Timestamp + Lattice,

type Key<'a> = <B as BatchReader>::Key<'a>

type KeyOwned = <B as BatchReader>::KeyOwned

type Val<'a> = <B as BatchReader>::Val<'a>

type ValOwned = <B as BatchReader>::ValOwned

type Time = <B as BatchReader>::Time

type Diff = <B as BatchReader>::Diff

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

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

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

type Key<'a> = <B as BatchReader>::Key<'a>

type KeyOwned = <B as BatchReader>::KeyOwned

type Val<'a> = <B as BatchReader>::Val<'a>

type ValOwned = <B as BatchReader>::ValOwned

type Time = <B as BatchReader>::Time

type Diff = <B as BatchReader>::Diff

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

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

where B: BatchReader, B::Time: Clone, F: Fn(&B::Time) -> Option<B::Time>,

type Key<'a> = <B as BatchReader>::Key<'a>

type KeyOwned = <B as BatchReader>::KeyOwned

type Val<'a> = <B as BatchReader>::Val<'a>

type ValOwned = <B as BatchReader>::ValOwned

type Time = <B as BatchReader>::Time

type Diff = <B as BatchReader>::Diff

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

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

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

type Key<'a> = <B as BatchReader>::Key<'a>

type KeyOwned = <B as BatchReader>::KeyOwned

type Val<'a> = <B as BatchReader>::Val<'a>

type ValOwned = <B as BatchReader>::ValOwned

type Time = TInner

type Diff = <B as BatchReader>::Diff

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, B::Time: Timestamp, TInner: Refines<B::Time> + Lattice, F: FnMut(B::Key<'_>, <B::Cursor as Cursor>::Val<'_>, &B::Time) -> TInner + Clone,

type Key<'a> = <B as BatchReader>::Key<'a>

type KeyOwned = <B as BatchReader>::KeyOwned

type Val<'a> = <B as BatchReader>::Val<'a>

type ValOwned = <B as BatchReader>::ValOwned

type Time = TInner

type Diff = <B as BatchReader>::Diff

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

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

type Key<'a> = <<L as Layout>::KeyContainer as BatchContainer>::ReadItem<'a>

type KeyOwned = <<L as Layout>::Target as Update>::Key

type Val<'a> = &'a ()

type ValOwned = ()

type Time = <<L as Layout>::Target as Update>::Time

type Diff = <<L as Layout>::Target as Update>::Diff

type Cursor = OrdKeyCursor<L>

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

type Key<'a> = <<L as Layout>::KeyContainer as BatchContainer>::ReadItem<'a>

type KeyOwned = <<L as Layout>::Target as Update>::Key

type Val<'a> = <<L as Layout>::ValContainer as BatchContainer>::ReadItem<'a>

type ValOwned = <<L as Layout>::Target as Update>::Val

type Time = <<L as Layout>::Target as Update>::Time

type Diff = <<L as Layout>::Target as Update>::Diff

type Cursor = OrdValCursor<L>