<E, EB, A2, E2, R2, X extends Cause.Cause<any>>(
filter: Filter.Filter<Cause.Cause<E>, EB, X>,
f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>
): <A, R>(
self: Stream<A, E, R>
) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>
<A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(
self: Stream<A, E, R>,
filter: Filter.Filter<Cause.Cause<E>, EB, X>,
f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>
): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>Recovers from stream failures by filtering the Cause and switching to a
recovery stream.
When to use
Use when you need to recover a stream only from causes selected by a
Filter, while giving the recovery both the selected value and the original
Cause.
Details
The filter is applied to the full Cause. A successful filter result is
passed to f together with the original cause; a failed filter result
re-fails with the residual cause.
export const const catchCauseFilter: {
<E, EB, A2, E2, R2, X extends Cause.Cause<any>>(
filter: Filter.Filter<Cause.Cause<E>, EB, X>,
f: (
failure: EB,
cause: Cause.Cause<E>
) => Stream<A2, E2, R2>
): <A, R>(
self: Stream<A, E, R>
) => Stream<
A | A2,
Cause.Cause.Error<X> | E2,
R2 | R
>
<
A,
E,
R,
EB,
A2,
E2,
R2,
X extends Cause.Cause<any>
>(
self: Stream<A, E, R>,
filter: Filter.Filter<Cause.Cause<E>, EB, X>,
f: (
failure: EB,
cause: Cause.Cause<E>
) => Stream<A2, E2, R2>
): Stream<
A | A2,
Cause.Cause.Error<X> | E2,
R | R2
>
}
Recovers from stream failures by filtering the Cause and switching to a
recovery stream.
When to use
Use when you need to recover a stream only from causes selected by a
Filter, while giving the recovery both the selected value and the original
Cause.
Details
The filter is applied to the full Cause. A successful filter result is
passed to f together with the original cause; a failed filter result
re-fails with the residual cause.
catchCauseFilter: {
<function (type parameter) E in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>E, function (type parameter) EB in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>EB, function (type parameter) A2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>A2, function (type parameter) E2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>E2, function (type parameter) R2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>R2, function (type parameter) X in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>X extends import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<any>>(
filter: Filter.Filter<Cause.Cause<E>, EB, X>filter: import FilterFilter.interface Filter<in Input, out Pass = Input, out Fail = Input>Represents a filter function that can transform inputs to outputs or filter them out.
Details
A filter takes an input value and either returns a boxed pass value or the
special fail type to indicate the value should be filtered out.
Example (Defining a positive number filter)
import { Filter, Result } from "effect"
// A filter that only passes positive numbers
const positiveFilter: Filter.Filter<number> = (n) => n > 0 ? Result.succeed(n) : Result.fail(n)
console.log(positiveFilter(5)) // Result.succeed(5)
console.log(positiveFilter(-3)) // Result.fail(-3)
Filter<import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<function (type parameter) E in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>E>, function (type parameter) EB in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>EB, function (type parameter) X in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>X>,
f: (
failure: EB,
cause: Cause.Cause<E>
) => Stream<A2, E2, R2>
failure: EBfailure: function (type parameter) EB in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>EB, cause: Cause.Cause<E>(parameter) cause: {
reasons: ReadonlyArray<Reason<E>>;
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; <…;
toString: () => string;
toJSON: () => unknown;
}
import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<function (type parameter) E in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>E>) => 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) A2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>A2, function (type parameter) E2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>E2, function (type parameter) R2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>R2>
): <function (type parameter) A in <A, R>(self: Stream<A, E, R>): Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>A, function (type parameter) R in <A, R>(self: Stream<A, E, R>): Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | 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, R>(self: Stream<A, E, R>): Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>A, function (type parameter) E in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>E, function (type parameter) R in <A, R>(self: Stream<A, E, R>): Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | 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, R>(self: Stream<A, E, R>): Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>A | function (type parameter) A2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>A2, import CauseCause.Cause.type Cause<out E>.Error<T> = T extends Cause.Cause<infer E> ? E : neverExtracts the error type E from a Cause<E>.
Example (Extracting the error type)
import type { Cause } from "effect"
// string
type E = Cause.Cause.Error<Cause.Cause<string>>
Error<function (type parameter) X in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>X> | function (type parameter) E2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>E2, function (type parameter) R2 in <E, EB, A2, E2, R2, X extends Cause.Cause<any>>(filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): <A, R>(self: Stream<A, E, R>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>R2 | function (type parameter) R in <A, R>(self: Stream<A, E, R>): Stream<A | A2, Cause.Cause.Error<X> | E2, R2 | R>R>
<function (type parameter) A in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A, function (type parameter) E in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E, function (type parameter) R in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R, function (type parameter) EB in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>EB, function (type parameter) A2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A2, function (type parameter) E2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E2, function (type parameter) R2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R2, function (type parameter) X in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>X extends import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<any>>(
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, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A, function (type parameter) E in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E, function (type parameter) R in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R>,
filter: Filter.Filter<Cause.Cause<E>, EB, X>filter: import FilterFilter.interface Filter<in Input, out Pass = Input, out Fail = Input>Represents a filter function that can transform inputs to outputs or filter them out.
Details
A filter takes an input value and either returns a boxed pass value or the
special fail type to indicate the value should be filtered out.
Example (Defining a positive number filter)
import { Filter, Result } from "effect"
// A filter that only passes positive numbers
const positiveFilter: Filter.Filter<number> = (n) => n > 0 ? Result.succeed(n) : Result.fail(n)
console.log(positiveFilter(5)) // Result.succeed(5)
console.log(positiveFilter(-3)) // Result.fail(-3)
Filter<import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<function (type parameter) E in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E>, function (type parameter) EB in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>EB, function (type parameter) X in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>X>,
f: (
failure: EB,
cause: Cause.Cause<E>
) => Stream<A2, E2, R2>
failure: EBfailure: function (type parameter) EB in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>EB, cause: Cause.Cause<E>(parameter) cause: {
reasons: ReadonlyArray<Reason<E>>;
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; <…;
toString: () => string;
toJSON: () => unknown;
}
import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<function (type parameter) E in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E>) => 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) A2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A2, function (type parameter) E2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E2, function (type parameter) R2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R2>
): 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, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A | function (type parameter) A2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A2, import CauseCause.Cause.type Cause<out E>.Error<T> = T extends Cause.Cause<infer E> ? E : neverExtracts the error type E from a Cause<E>.
Example (Extracting the error type)
import type { Cause } from "effect"
// string
type E = Cause.Cause.Error<Cause.Cause<string>>
Error<function (type parameter) X in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>X> | function (type parameter) E2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E2, function (type parameter) R in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R | function (type parameter) R2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R2>
} = dual<(...args: Array<any>) => any, <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>>(arity: 3, body: <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>): ((...args: Array<any>) => any) & (<A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>) => Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>) (+1 overload)Creates a function that can be called in data-first style or data-last
(pipe-friendly) style.
When to use
Use to expose one implementation through both direct and pipe-friendly
call styles.
Details
Pass either the arity of the uncurried function or a predicate that decides
whether the current call is data-first. Arity is the common case. Use a
predicate when optional arguments make arity ambiguous.
Example (Selecting data-first or data-last style by arity)
import { Function, pipe } from "effect"
const sum = Function.dual<
(that: number) => (self: number) => number,
(self: number, that: number) => number
>(2, (self, that) => self + that)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
Example (Defining overloads with call signatures)
import { Function, pipe } from "effect"
const sum: {
(that: number): (self: number) => number
(self: number, that: number): number
} = Function.dual(2, (self: number, that: number): number => self + that)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
Example (Selecting data-first or data-last style with a predicate)
import { Function, pipe } from "effect"
const sum = Function.dual<
(that: number) => (self: number) => number,
(self: number, that: number) => number
>(
(args) => args.length === 2,
(self, that) => self + that
)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
dual(3, <function (type parameter) A in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A, function (type parameter) E in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E, function (type parameter) R in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R, function (type parameter) EB in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>EB, function (type parameter) A2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A2, function (type parameter) E2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E2, function (type parameter) R2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R2, function (type parameter) X in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>X extends import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<any>>(
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, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A, function (type parameter) E in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E, function (type parameter) R in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R>,
filter: Filter.Filter<Cause.Cause<E>, EB, X>filter: import FilterFilter.interface Filter<in Input, out Pass = Input, out Fail = Input>Represents a filter function that can transform inputs to outputs or filter them out.
Details
A filter takes an input value and either returns a boxed pass value or the
special fail type to indicate the value should be filtered out.
Example (Defining a positive number filter)
import { Filter, Result } from "effect"
// A filter that only passes positive numbers
const positiveFilter: Filter.Filter<number> = (n) => n > 0 ? Result.succeed(n) : Result.fail(n)
console.log(positiveFilter(5)) // Result.succeed(5)
console.log(positiveFilter(-3)) // Result.fail(-3)
Filter<import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<function (type parameter) E in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E>, function (type parameter) EB in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>EB, function (type parameter) X in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>X>,
f: (
failure: EB,
cause: Cause.Cause<E>
) => Stream<A2, E2, R2>
failure: EBfailure: function (type parameter) EB in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>EB, cause: Cause.Cause<E>(parameter) cause: {
reasons: ReadonlyArray<Reason<E>>;
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; <…;
toString: () => string;
toJSON: () => unknown;
}
import CauseCause.interface Cause<out E>A structured representation of how an Effect failed.
When to use
Use to preserve the full structured failure information for an effect instead
of collapsing it to a single error value.
Details
Access the individual failure entries through the reasons array, then
narrow each entry with
isFailReason
,
isDieReason
, or
- Use
hasFails
/
hasDies
/
hasInterrupts
to test
for the presence of specific reason kinds without iterating.
- Use
findError
/
findDefect
to extract the first value
of a given kind.
- Use
combine
to merge two causes.
Cause implements Equal — two causes with the same reasons (by value)
compare as equal.
Example (Creating and inspecting a cause)
import { Cause } from "effect"
const cause = Cause.fail("Something went wrong")
console.log(cause.reasons.length) // 1
console.log(Cause.isFailReason(cause.reasons[0])) // true
Companion namespace for the Cause interface.
Cause<function (type parameter) E in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E>) => 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) A2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A2, function (type parameter) E2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E2, function (type parameter) R2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R2>
): 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, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A | function (type parameter) A2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>A2, import CauseCause.Cause.type Cause<out E>.Error<T> = T extends Cause.Cause<infer E> ? E : neverExtracts the error type E from a Cause<E>.
Example (Extracting the error type)
import type { Cause } from "effect"
// string
type E = Cause.Cause.Error<Cause.Cause<string>>
Error<function (type parameter) X in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>X> | function (type parameter) E2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>E2, function (type parameter) R in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R | function (type parameter) R2 in <A, E, R, EB, A2, E2, R2, X extends Cause.Cause<any>>(self: Stream<A, E, R>, filter: Filter.Filter<Cause.Cause<E>, EB, X>, f: (failure: EB, cause: Cause.Cause<E>) => Stream<A2, E2, R2>): Stream<A | A2, Cause.Cause.Error<X> | E2, R | R2>R2> =>
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(
import ChannelChannel.const catchCauseFilter: {
<
OutErr,
EB,
X extends Cause.Cause<any>,
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>(
filter: Filter.Filter<
Cause.Cause<OutErr>,
EB,
X
>,
f: (
failure: EB,
cause: Cause.Cause<OutErr>
) => Channel<
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>
): <
OutElem,
OutDone,
InElem,
InErr,
InDone,
Env
>(
self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>
) => Channel<
OutElem | OutElem1,
Cause.Cause.Error<X> | OutErr1,
OutDone | OutDone1,
InElem & InElem1,
InErr & InErr1,
InDone & InDone1,
Env | Env1
>
<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env,
EB,
X extends Cause.Cause<any>,
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>(
self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>,
filter: Filter.Filter<
Cause.Cause<OutErr>,
EB,
X
>,
f: (
failure: EB,
cause: Cause.Cause<OutErr>
) => Channel<
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>
): Channel<
OutElem | OutElem1,
Cause.Cause.Error<X> | OutErr1,
OutDone | OutDone1,
InElem & InElem1,
InErr & InErr1,
InDone & InDone1,
Env | Env1
>
}
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; <…;
}
filter: Filter.Filter<Cause.Cause<E>, EB, X>filter,
(failure: EBfailure, cause: Cause.Cause<E>(parameter) cause: {
reasons: ReadonlyArray<Reason<E>>;
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; <…;
toString: () => string;
toJSON: () => unknown;
}
f: (
failure: EB,
cause: Cause.Cause<E>
) => Stream<A2, E2, R2>
failure: EBfailure, cause: Cause.Cause<E>(parameter) cause: {
reasons: ReadonlyArray<Reason<E>>;
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; <…;
toString: () => string;
toJSON: () => unknown;
}
Stream<A2, E2, R2>.channel: Channel.Channel<Arr.NonEmptyReadonlyArray<A>, E, void, unknown, unknown, unknown, R>(property) Stream<A2, E2, R2>.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; <…;
}