<A, E, R>(self: Stream<A, E, R>): Stream<
Arr.NonEmptyReadonlyArray<A>,
E,
R
>Exposes the underlying chunks as a stream of non-empty arrays.
Example (Exposing stream chunks)
import { Console, Effect, Stream } from "effect"
const program = Effect.gen(function*() {
const chunks = yield* Stream.make(1, 2, 3, 4).pipe(
Stream.rechunk(2),
Stream.chunks,
Stream.runCollect
)
yield* Console.log(chunks)
})
Effect.runPromise(program)
// Output: [ [ 1, 2 ], [ 3, 4 ] ]grouping
Source effect/Stream.ts:69985 lines
export const const chunks: <A, E, R>(
self: Stream<A, E, R>
) => Stream<Arr.NonEmptyReadonlyArray<A>, E, R>
Exposes the underlying chunks as a stream of non-empty arrays.
Example (Exposing stream chunks)
import { Console, Effect, Stream } from "effect"
const program = Effect.gen(function*() {
const chunks = yield* Stream.make(1, 2, 3, 4).pipe(
Stream.rechunk(2),
Stream.chunks,
Stream.runCollect
)
yield* Console.log(chunks)
})
Effect.runPromise(program)
// Output: [ [ 1, 2 ], [ 3, 4 ] ]
chunks = <function (type parameter) A in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>R>(self: Stream<A, E, R>(parameter) self: {
channel: Channel.Channel<Arr.NonEmptyReadonlyArray<A>, E, void, unknown, unknown, unknown, R>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
interface Stream<out A, out E = never, out R = never>A Stream<A, E, R> describes a program that can emit many A values, fail
with E, and require R.
Details
Streams are pull-based with backpressure and emit chunks to amortize effect
evaluation. They support monadic composition and error handling similar to
Effect, adapted for multiple values.
Example (Creating and consuming streams)
import { Console, Effect, Stream } from "effect"
const program = Effect.gen(function*() {
yield* Stream.make(1, 2, 3).pipe(
Stream.map((n) => n * 2),
Stream.runForEach((n) => Console.log(n))
)
})
Effect.runPromise(program)
// Output:
// 2
// 4
// 6
Stream<function (type parameter) A in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>R>): interface Stream<out A, out E = never, out R = never>A Stream<A, E, R> describes a program that can emit many A values, fail
with E, and require R.
Details
Streams are pull-based with backpressure and emit chunks to amortize effect
evaluation. They support monadic composition and error handling similar to
Effect, adapted for multiple values.
Example (Creating and consuming streams)
import { Console, Effect, Stream } from "effect"
const program = Effect.gen(function*() {
yield* Stream.make(1, 2, 3).pipe(
Stream.map((n) => n * 2),
Stream.runForEach((n) => Console.log(n))
)
})
Effect.runPromise(program)
// Output:
// 2
// 4
// 6
Stream<import ArrArr.type NonEmptyReadonlyArray<A> = readonly [
A,
...A[]
]
A readonly array guaranteed to have at least one element.
When to use
Use when non-emptiness must be tracked at the type level while preventing mutation.
Many Array module functions accept or return this type.
Example (Typing a non-empty array)
import type { Array } from "effect"
const nonEmpty: Array.NonEmptyReadonlyArray<number> = [1, 2, 3]
const head: number = nonEmpty[0] // guaranteed to exist
NonEmptyReadonlyArray<function (type parameter) A in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>A>, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>): Stream<Arr.NonEmptyReadonlyArray<A>, E, R>R> =>
self: Stream<A, E, R>(parameter) self: {
channel: Channel.Channel<Arr.NonEmptyReadonlyArray<A>, E, void, unknown, unknown, unknown, R>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
Stream<A, E, R>.channel: Channel.Channel<Arr.NonEmptyReadonlyArray<A>, E, void, unknown, unknown, unknown, R>(property) Stream<A, E, R>.channel: {
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
Pipeable.pipe<Channel.Channel<readonly [A, ...A[]], E, void, unknown, unknown, unknown, R>, Channel.Channel<[readonly [A, ...A[]], ...(readonly [A, ...A[]])[]], E, void, unknown, unknown, unknown, R>, Stream<readonly [A, ...A[]], E, R>>(this: Channel.Channel<readonly [A, ...A[]], E, void, unknown, unknown, unknown, R>, ab: (_: Channel.Channel<readonly [A, ...A[]], E, void, unknown, unknown, unknown, R>) => Channel.Channel<[readonly [A, ...A[]], ...(readonly [A, ...A[]])[]], E, void, unknown, unknown, unknown, R>, bc: (_: Channel.Channel<[readonly [A, ...A[]], ...(readonly [A, ...A[]])[]], E, void, unknown, unknown, unknown, R>) => Stream<readonly [A, ...A[]], E, R>): Stream<...> (+21 overloads)pipe(
import ChannelChannel.const map: {
<OutElem, OutElem2>(
f: (o: OutElem, i: number) => OutElem2
): <
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>(
self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>
) => Channel<
OutElem2,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>
<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env,
OutElem2
>(
self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>,
f: (o: OutElem, i: number) => OutElem2
): Channel<
OutElem2,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>
}
import ArrArr.const of: <A>(a: A) => NonEmptyArray<A>Wraps a single value in a NonEmptyArray.
Example (Creating a single-element array)
import { Array } from "effect"
console.log(Array.of(1)) // [1]
of),
const fromChannel: <
Arr extends Arr.NonEmptyReadonlyArray<any>,
E,
R
>(
channel: Channel.Channel<
Arr,
E,
void,
unknown,
unknown,
unknown,
R
>
) => Stream<
Arr extends Arr.NonEmptyReadonlyArray<infer A>
? A
: never,
E,
R
>
Creates a stream from a array-emitting Channel.
Example (Creating a stream from an array-emitting channel)
import { Channel, Console, Effect, Stream } from "effect"
const program = Effect.gen(function*() {
const channel = Channel.succeed([1, 2, 3] as const)
const stream = Stream.fromChannel(channel)
const result = yield* Stream.runCollect(stream)
yield* Console.log(result)
})
// Output: [ 1, 2, 3 ]
fromChannel
)Referenced by 1 symbols