Struct differential_dataflow::trace::wrappers::enter_at::BatchCursorEnter

pub struct BatchCursorEnter<K, V, T, R, B: BatchReader<K, V, T, R>, TInner, F> { /* fields omitted */ }

Wrapper to provide cursor to nested scope.

Trait Implementations

impl<K, V, T, R, TInner, B: BatchReader<K, V, T, R>, F> Cursor<K, V, TInner, R> for BatchCursorEnter<K, V, T, R, B, TInner, F> where
    T: Timestamp,
    TInner: Refines<T> + Lattice,
    F: FnMut(&K, &V, &T) -> TInner, 

type Storage = BatchEnter<K, V, T, R, B, TInner, F>

Type the cursor addresses data in.

fn key_valid(&self, storage: &Self::Storage) -> bool

Indicates if the current key is valid.

fn val_valid(&self, storage: &Self::Storage) -> bool

Indicates if the current value is valid.

fn key<'a>(&self, storage: &'a Self::Storage) -> &'a K

A reference to the current key. Asserts if invalid.

fn val<'a>(&self, storage: &'a Self::Storage) -> &'a V

A reference to the current value. Asserts if invalid.

fn map_times<L: FnMut(&TInner, &R)>(
    &mut self,
    storage: &Self::Storage,
    logic: L
)

Applies logic to each pair of time and difference. Intended for mutation of the closure’s scope.

fn step_key(&mut self, storage: &Self::Storage)

Advances the cursor to the next key.

fn seek_key(&mut self, storage: &Self::Storage, key: &K)

Advances the cursor to the specified key.

fn step_val(&mut self, storage: &Self::Storage)

Advances the cursor to the next value.

fn seek_val(&mut self, storage: &Self::Storage, val: &V)

Advances the cursor to the specified value.

fn rewind_keys(&mut self, storage: &Self::Storage)

Rewinds the cursor to the first key.

fn rewind_vals(&mut self, storage: &Self::Storage)

Rewinds the cursor to the first value for current key.

fn get_key<'a>(&self, storage: &'a Self::Storage) -> Option<&'a K>

Returns a reference to the current key, if valid.

fn get_val<'a>(&self, storage: &'a Self::Storage) -> Option<&'a V>

Returns a reference to the current value, if valid.