Trait differential_dataflow::trace::Builder

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pub trait Builder: Sized {
    type Input;
    type Time: Timestamp;
    type Output;

    // Required methods
    fn with_capacity(keys: usize, vals: usize, upds: usize) -> Self;
    fn copy(&mut self, element: &Self::Input);
    fn done(
        self,
        lower: Antichain<Self::Time>,
        upper: Antichain<Self::Time>,
        since: Antichain<Self::Time>
    ) -> Self::Output;

    // Provided methods
    fn new() -> Self { ... }
    fn push(&mut self, element: Self::Input) { ... }
}

Expand description

Functionality for building batches from ordered update sequences.

Required Associated Types§

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type Input

Input item type.

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type Time: Timestamp

Timestamp type.

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type Output

Output batch type.

Required Methods§

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fn with_capacity(keys: usize, vals: usize, upds: usize) -> Self

Allocates an empty builder with capacity for the specified keys, values, and updates.

They represent respectively the number of distinct key, (key, val), and total updates.

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fn copy(&mut self, element: &Self::Input)

Adds an element to the batch.

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fn done( self, lower: Antichain<Self::Time>, upper: Antichain<Self::Time>, since: Antichain<Self::Time> ) -> Self::Output

Completes building and returns the batch.

Provided Methods§

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fn new() -> Self

Allocates an empty builder.

Ideally we deprecate this and insist all non-trivial building happens via with_capacity().

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fn push(&mut self, element: Self::Input)

Adds an element to the batch.

The default implementation uses self.copy with references to the owned arguments. One should override it if the builder can take advantage of owned arguments.