Function batch

batch<V>(size?: number): Task<V, readonly V[]>
Creates a task collecting consecutive items into fixed-size batches.

Batches are emitted as soon as they fill up, in source order and with items in source order; the last batch is emitted short if the feed ends before it fills up, and no batch is emitted at all for an empty feed.
Warning
- Incremental: batches are emitted as they fill up where size is positive, so the reported feed runs dry as the feed drawn from does; an unbounded size drains the whole feed before emitting the single batch holding it, so an infinite feed never completes.
- Materialising: an unbounded size holds the whole feed in memory, so a large feed may exhaust it; batch by a positive size to keep consumption bounded.
- Stateful: items are collected across draws, so a task invoked per nested feed or per run batches each independently, closing every one with a short batch rather than filling it from the items that follow.
Type Parameters
- V
  The type of items in the feed
Parameters
- size: number = 0
  The maximum number of items per batch, defaulting to 0; values less than 1 are treated as unbounded, collecting the whole feed into a single batch
Returns Task<V, readonly V[]>
A task yielding the read-only lists of the items collected into each batch
Throws
TypeError If size is not an integer
Example
```
await pipe(
  (items([1, 2, 3, 4, 5]))
  (batch(2))
  (toArray())
);  // [[1, 2], [3, 4], [5]]

await pipe(
  (items([1, 2, 3]))
  (batch())
  (toArray())
);  // [[1, 2, 3]]
```
- Defined in tasks/batch.ts:63

Function batch

Type Parameters

Parameters

Returns Task<V, readonly V[]>

Throws

Example

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