<A>(options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?: "enforce" | "shape" | undefined
}): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>
<A, E, R>(
self: Stream<A, E, R>,
options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?: "enforce" | "shape" | undefined
}
): Stream<A, E, R>Rate-limits stream chunks with a synchronous cost function.
When to use
Use to throttle chunks when each chunk's cost can be computed synchronously.
Details
Uses a token bucket. The bucket can accumulate up to units + burst tokens,
and each chunk consumes the cost returned by cost.
If using the "enforce" strategy, arrays that do not meet the bandwidth constraints are dropped. If using the "shape" strategy, arrays are delayed until they can be emitted without exceeding the bandwidth constraints.
Defaults to the "shape" strategy.
Example (Throttling stream chunks)
import { Console, Effect, Schedule, Stream } from "effect"
const stream = Stream.fromSchedule(Schedule.spaced("50 millis")).pipe(
Stream.take(6),
Stream.throttle({
cost: (arr) => arr.length,
units: 1,
duration: "100 millis",
strategy: "shape"
})
)
const program = Effect.gen(function*() {
const values = yield* Stream.runCollect(stream)
yield* Console.log(values)
// Output: [ 0, 1, 2, 3, 4, 5 ]
})rate limiting
Source effect/Stream.ts:811935 lines
export const const throttle: {
<A>(options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}): <E, R>(
self: Stream<A, E, R>
) => Stream<A, E, R>
<A, E, R>(
self: Stream<A, E, R>,
options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}
): Stream<A, E, R>
}
Rate-limits stream chunks with a synchronous cost function.
When to use
Use to throttle chunks when each chunk's cost can be computed synchronously.
Details
Uses a token bucket. The bucket can accumulate up to units + burst tokens,
and each chunk consumes the cost returned by cost.
If using the "enforce" strategy, arrays that do not meet the bandwidth
constraints are dropped. If using the "shape" strategy, arrays are delayed
until they can be emitted without exceeding the bandwidth constraints.
Defaults to the "shape" strategy.
Example (Throttling stream chunks)
import { Console, Effect, Schedule, Stream } from "effect"
const stream = Stream.fromSchedule(Schedule.spaced("50 millis")).pipe(
Stream.take(6),
Stream.throttle({
cost: (arr) => arr.length,
units: 1,
duration: "100 millis",
strategy: "shape"
})
)
const program = Effect.gen(function*() {
const values = yield* Stream.runCollect(stream)
yield* Console.log(values)
// Output: [ 0, 1, 2, 3, 4, 5 ]
})
throttle: {
<function (type parameter) A in <A>(options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>
options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}
cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
arr: Arr.NonEmptyReadonlyArray<A>(parameter) arr: {
0: A;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<A>>): Array<A>; (...items: Array<A | ConcatArray<A>>): Array<A> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<A>;
indexOf: (searchElement: A, fromIndex?: number) => number;
lastIndexOf: (searchElement: A, fromIndex?: number) => number;
every: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => void, thisArg?: any) => void;
map: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): Array<S>; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): Array<A> };
reduce: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
reduceRight: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
find: { (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findIndex: (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, A]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<A>;
includes: (searchElement: A, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: A, index: number, array: Array<A>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => A | undefined;
findLast: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findLastIndex: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
toReversed: () => Array<A>;
toSorted: (compareFn?: ((a: A, b: A) => number) | undefined) => Array<A>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<A>): Array<A>; (start: number, deleteCount?: number): Array<A> };
with: (index: number, value: A) => Array<A>;
}
import ArrArr.type Arr.NonEmptyReadonlyArray = /*unresolved*/ anyNonEmptyReadonlyArray<function (type parameter) A in <A>(options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>
units: numberunits: number
readonly duration: Duration.Inputduration: import DurationDuration.type Duration.Input = /*unresolved*/ anyInput
readonly burst?: number | undefinedburst?: number | undefined
readonly strategy?: "enforce" | "shape" | undefinedstrategy?: "enforce" | "shape" | undefined
}): <function (type parameter) E in <E, R>(self: Stream<A, E, R>): Stream<A, E, R>E, function (type parameter) R in <E, R>(self: Stream<A, E, R>): Stream<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>(options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>
function (type parameter) E in <E, R>(self: Stream<A, E, R>): Stream<A, E, R>E, function (type parameter) R in <E, R>(self: Stream<A, E, R>): Stream<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<function (type parameter) A in <A>(options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>
function (type parameter) E in <E, R>(self: Stream<A, E, R>): Stream<A, E, R>E, function (type parameter) R in <E, R>(self: Stream<A, E, R>): Stream<A, E, R>R>
<function (type parameter) A in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, 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; <…;
}
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>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}
cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
arr: Arr.NonEmptyReadonlyArray<A>(parameter) arr: {
0: A;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<A>>): Array<A>; (...items: Array<A | ConcatArray<A>>): Array<A> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<A>;
indexOf: (searchElement: A, fromIndex?: number) => number;
lastIndexOf: (searchElement: A, fromIndex?: number) => number;
every: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => void, thisArg?: any) => void;
map: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): Array<S>; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): Array<A> };
reduce: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
reduceRight: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
find: { (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findIndex: (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, A]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<A>;
includes: (searchElement: A, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: A, index: number, array: Array<A>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => A | undefined;
findLast: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findLastIndex: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
toReversed: () => Array<A>;
toSorted: (compareFn?: ((a: A, b: A) => number) | undefined) => Array<A>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<A>): Array<A>; (start: number, deleteCount?: number): Array<A> };
with: (index: number, value: A) => Array<A>;
}
import ArrArr.type Arr.NonEmptyReadonlyArray = /*unresolved*/ anyNonEmptyReadonlyArray<function (type parameter) A in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
units: numberunits: number
readonly duration: Duration.Inputduration: import DurationDuration.type Duration.Input = /*unresolved*/ anyInput
readonly burst?: number | undefinedburst?: number | undefined
readonly strategy?: "enforce" | "shape" | undefinedstrategy?: "enforce" | "shape" | undefined
}
): 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>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
import dualdual(
2,
<function (type parameter) A in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, 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; <…;
}
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>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}
cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
arr: Arr.NonEmptyReadonlyArray<A>(parameter) arr: {
0: A;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<A>>): Array<A>; (...items: Array<A | ConcatArray<A>>): Array<A> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<A>;
indexOf: (searchElement: A, fromIndex?: number) => number;
lastIndexOf: (searchElement: A, fromIndex?: number) => number;
every: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => void, thisArg?: any) => void;
map: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): Array<S>; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): Array<A> };
reduce: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
reduceRight: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
find: { (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findIndex: (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, A]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<A>;
includes: (searchElement: A, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: A, index: number, array: Array<A>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => A | undefined;
findLast: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findLastIndex: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
toReversed: () => Array<A>;
toSorted: (compareFn?: ((a: A, b: A) => number) | undefined) => Array<A>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<A>): Array<A>; (start: number, deleteCount?: number): Array<A> };
with: (index: number, value: A) => Array<A>;
}
import ArrArr.type Arr.NonEmptyReadonlyArray = /*unresolved*/ anyNonEmptyReadonlyArray<function (type parameter) A in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
units: numberunits: number
readonly duration: Duration.Inputduration: import DurationDuration.type Duration.Input = /*unresolved*/ anyInput
readonly burst?: number | undefinedburst?: number | undefined
readonly strategy?: "enforce" | "shape" | undefinedstrategy?: "enforce" | "shape" | undefined
}
): 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>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, options: {
readonly cost: (arr: Arr.NonEmptyReadonlyArray<A>) => number;
readonly units: number;
readonly duration: Duration.Input;
readonly burst?: number | undefined;
readonly strategy?: "enforce" | "shape" | undefined;
}): Stream<A, E, R>
const throttleEffect: {
<A, E2, R2>(options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => Effect.Effect<number, E2, R2>
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}): <E, R>(
self: Stream<A, E, R>
) => Stream<A, E2 | E, R2 | R>
<A, E, R, E2, R2>(
self: Stream<A, E, R>,
options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => Effect.Effect<number, E2, R2>
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}
): Stream<A, E | E2, R | R2>
}
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; <…;
}
options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}
cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => Effect.Effect<number, E, R>
arr: Arr.NonEmptyReadonlyArray<A>(parameter) arr: {
0: A;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<A>>): Array<A>; (...items: Array<A | ConcatArray<A>>): Array<A> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<A>;
indexOf: (searchElement: A, fromIndex?: number) => number;
lastIndexOf: (searchElement: A, fromIndex?: number) => number;
every: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => void, thisArg?: any) => void;
map: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): Array<S>; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): Array<A> };
reduce: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
reduceRight: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
find: { (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findIndex: (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, A]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<A>;
includes: (searchElement: A, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: A, index: number, array: Array<A>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => A | undefined;
findLast: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findLastIndex: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
toReversed: () => Array<A>;
toSorted: (compareFn?: ((a: A, b: A) => number) | undefined) => Array<A>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<A>): Array<A>; (start: number, deleteCount?: number): Array<A> };
with: (index: number, value: A) => Array<A>;
}
import EffectEffect.succeed(options: {
readonly cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
readonly units: number
readonly duration: Duration.Input
readonly burst?: number | undefined
readonly strategy?:
| "enforce"
| "shape"
| undefined
}
cost: (
arr: Arr.NonEmptyReadonlyArray<A>
) => number
arr: Arr.NonEmptyReadonlyArray<A>(parameter) arr: {
0: A;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<A>>): Array<A>; (...items: Array<A | ConcatArray<A>>): Array<A> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<A>;
indexOf: (searchElement: A, fromIndex?: number) => number;
lastIndexOf: (searchElement: A, fromIndex?: number) => number;
every: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => void, thisArg?: any) => void;
map: (callbackfn: (value: A, index: number, array: ReadonlyArray<A>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): Array<S>; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): Array<A> };
reduce: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
reduceRight: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: ReadonlyArray<A>) => A, initialValue: A): A; (callbac…;
find: { (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findIndex: (predicate: (value: A, index: number, obj: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, A]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<A>;
includes: (searchElement: A, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: A, index: number, array: Array<A>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => A | undefined;
findLast: { (predicate: (value: A, index: number, array: ReadonlyArray<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any): A | undefined };
findLastIndex: (predicate: (value: A, index: number, array: ReadonlyArray<A>) => unknown, thisArg?: any) => number;
toReversed: () => Array<A>;
toSorted: (compareFn?: ((a: A, b: A) => number) | undefined) => Array<A>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<A>): Array<A>; (start: number, deleteCount?: number): Array<A> };
with: (index: number, value: A) => Array<A>;
}