<A, E, R>(self: Stream<A, E, R>): Stream<[A, number], E, R>Zips this stream together with the index of elements.
Example (Zipping elements with indices)
import { Console, Effect, Stream } from "effect"
const program = Effect.gen(function*() {
const indexed = yield* Stream.make("a", "b", "c", "d").pipe(
Stream.zipWithIndex,
Stream.runCollect
)
yield* Console.log(indexed)
})
Effect.runPromise(program)
// Output: [["a", 0], ["b", 1], ["c", 2], ["d", 3]]export const const zipWithIndex: <A, E, R>(
self: Stream<A, E, R>
) => Stream<[A, number], E, R>
Zips this stream together with the index of elements.
Example (Zipping elements with indices)
import { Console, Effect, Stream } from "effect"
const program = Effect.gen(function*() {
const indexed = yield* Stream.make("a", "b", "c", "d").pipe(
Stream.zipWithIndex,
Stream.runCollect
)
yield* Console.log(indexed)
})
Effect.runPromise(program)
// Output: [["a", 0], ["b", 1], ["c", 2], ["d", 3]]
zipWithIndex = <function (type parameter) A in <A, E, R>(self: Stream<A, E, R>): Stream<[A, number], E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>): Stream<[A, number], E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>): Stream<[A, number], 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<[A, number], E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>): Stream<[A, number], E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>): Stream<[A, number], 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<[function (type parameter) A in <A, E, R>(self: Stream<A, E, R>): Stream<[A, number], E, R>A, number], function (type parameter) E in <A, E, R>(self: Stream<A, E, R>): Stream<[A, number], E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>): Stream<[A, number], E, R>R> => const map: {
<A, B>(f: (a: A, i: number) => B): <E, R>(
self: Stream<A, E, R>
) => Stream<B, E, R>
<A, E, R, B>(
self: Stream<A, E, R>,
f: (a: A, i: number) => B
): Stream<B, E, 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; <…;
}
a: Aa, i: numberi) => [a: Aa, i: numberi])