<A>(predicate: (a: NoInfer<A>, index: number) => boolean): <E, R>(
self: Stream<A, E, R>
) => Stream<A, E, R>
<A, E, R>(
self: Stream<A, E, R>,
predicate: (a: NoInfer<A>, index: number) => boolean
): Stream<A, E, R>Drops elements until the specified predicate evaluates to true, then drops
that matching element.
Example (Dropping until a predicate matches)
import { Console, Effect, Stream } from "effect"
const stream = Stream.make(1, 2, 3, 4, 5)
const result = Stream.dropUntil(stream, (n) => n >= 3)
Effect.gen(function*() {
const output = yield* Stream.runCollect(result)
yield* Console.log(output) // Output: [ 4, 5 ]
})export const const dropUntil: {
<A>(
predicate: (
a: NoInfer<A>,
index: number
) => boolean
): <E, R>(
self: Stream<A, E, R>
) => Stream<A, E, R>
<A, E, R>(
self: Stream<A, E, R>,
predicate: (
a: NoInfer<A>,
index: number
) => boolean
): Stream<A, E, R>
}
Drops elements until the specified predicate evaluates to true, then drops
that matching element.
Example (Dropping until a predicate matches)
import { Console, Effect, Stream } from "effect"
const stream = Stream.make(1, 2, 3, 4, 5)
const result = Stream.dropUntil(stream, (n) => n >= 3)
Effect.gen(function*() {
const output = yield* Stream.runCollect(result)
yield* Console.log(output) // Output: [ 4, 5 ]
})
dropUntil: {
<function (type parameter) A in <A>(predicate: (a: NoInfer<A>, index: number) => boolean): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>A>(predicate: (
a: NoInfer<A>,
index: number
) => boolean
a: NoInfer<A>a: type NoInfer<A> = [A][A extends any ? 0 : never]Prevents TypeScript from inferring a type parameter from a specific
position.
When to use
Use when a function parameter must match an inferred type without becoming
an inference source.
Details
The parameter using NoInfer must still match the inferred type.
Example (Controlling inference)
import type { Types } from "effect"
declare function withDefault<T>(value: T, fallback: Types.NoInfer<T>): T
// T is inferred as "a" | "b" from the first argument only
const result = withDefault<"a" | "b">("a", "b")
NoInfer<function (type parameter) A in <A>(predicate: (a: NoInfer<A>, index: number) => boolean): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>A>, index: numberindex: number) => boolean): <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>(predicate: (a: NoInfer<A>, index: number) => boolean): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>A, 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>(predicate: (a: NoInfer<A>, index: number) => boolean): <E, R>(self: Stream<A, E, R>) => Stream<A, E, R>A, 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>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): 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, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>R>, predicate: (
a: NoInfer<A>,
index: number
) => boolean
a: NoInfer<A>a: type NoInfer<A> = [A][A extends any ? 0 : never]Prevents TypeScript from inferring a type parameter from a specific
position.
When to use
Use when a function parameter must match an inferred type without becoming
an inference source.
Details
The parameter using NoInfer must still match the inferred type.
Example (Controlling inference)
import type { Types } from "effect"
declare function withDefault<T>(value: T, fallback: Types.NoInfer<T>): T
// T is inferred as "a" | "b" from the first argument only
const result = withDefault<"a" | "b">("a", "b")
NoInfer<function (type parameter) A in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>A>, index: numberindex: number) => boolean): 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>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>R>
} = import dualdual(2, <function (type parameter) A in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): 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, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>R>,
predicate: (
a: NoInfer<A>,
index: number
) => boolean
a: NoInfer<A>a: type NoInfer<A> = [A][A extends any ? 0 : never]Prevents TypeScript from inferring a type parameter from a specific
position.
When to use
Use when a function parameter must match an inferred type without becoming
an inference source.
Details
The parameter using NoInfer must still match the inferred type.
Example (Controlling inference)
import type { Types } from "effect"
declare function withDefault<T>(value: T, fallback: Types.NoInfer<T>): T
// T is inferred as "a" | "b" from the first argument only
const result = withDefault<"a" | "b">("a", "b")
NoInfer<function (type parameter) A in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>A>, index: numberindex: number) => boolean
): 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>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>A, function (type parameter) E in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>E, function (type parameter) R in <A, E, R>(self: Stream<A, E, R>, predicate: (a: NoInfer<A>, index: number) => boolean): Stream<A, E, R>R> => const drop: {
(n: number): <A, E, R>(
self: Stream<A, E, R>
) => Stream<A, E, R>
<A, E, R>(
self: Stream<A, E, R>,
n: number
): Stream<A, E, R>
}
const dropWhile: {
<A>(
predicate: (
a: NoInfer<A>,
index: number
) => boolean
): <E, R>(
self: Stream<A, E, R>
) => Stream<A, E, R>
<A, E, R>(
self: Stream<A, E, R>,
predicate: (
a: NoInfer<A>,
index: number
) => boolean
): 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; <…;
}
a: NoInfer<A>a, i: numberi) => !predicate: (
a: NoInfer<A>,
index: number
) => boolean
a: NoInfer<A>a, i: numberi)), 1))