<
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
>Recovers from channel failures whose full Cause is selected by a Filter.
When to use
Use when you need to recover a channel only from causes selected by a
Filter, while giving the recovery both the selected value and the original
Cause.
Details
When the filter succeeds, the recovery function receives the selected value and the original cause. When the filter fails, the returned channel fails with the residual cause produced by the filter.
Source effect/Channel.ts:4212119 lines
export const 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
>
}
Recovers from channel failures whose full Cause is selected by a Filter.
When to use
Use when you need to recover a channel only from causes selected by a
Filter, while giving the recovery both the selected value and the original
Cause.
Details
When the filter succeeds, the recovery function receives the selected value
and the original cause. When the filter fails, the returned channel fails
with the residual cause produced by the filter.
catchCauseFilter: {
<
function (type parameter) OutErr in <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>OutErr,
function (type parameter) EB in <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>EB,
function (type parameter) X in <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>X extends import CauseCause.type Cause.Cause = /*unresolved*/ anyCause<any>,
function (type parameter) OutElem1 in <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>OutElem1,
function (type parameter) OutErr1 in <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>OutErr1,
function (type parameter) OutDone1 in <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>OutDone1,
function (type parameter) InElem1 in <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>InElem1,
function (type parameter) InErr1 in <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>InErr1,
function (type parameter) InDone1 in <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>InDone1,
function (type parameter) Env1 in <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>Env1
>(
filter: Filter.Filter<
Cause.Cause<OutErr>,
EB,
X
>
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.type Cause.Cause = /*unresolved*/ anyCause<function (type parameter) OutErr in <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>OutErr>, function (type parameter) EB in <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>EB, function (type parameter) X in <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>X>,
f: (
failure: EB,
cause: Cause.Cause<OutErr>
) => Channel<
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>
failure: EBfailure: function (type parameter) EB in <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>EB,
cause: Cause.Cause<OutErr>(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.type Cause.Cause = /*unresolved*/ anyCause<function (type parameter) OutErr in <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>OutErr>
) => interface Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<function (type parameter) OutElem1 in <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>OutElem1, function (type parameter) OutErr1 in <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>OutErr1, function (type parameter) OutDone1 in <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>OutDone1, function (type parameter) InElem1 in <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>InElem1, function (type parameter) InErr1 in <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>InErr1, function (type parameter) InDone1 in <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>InDone1, function (type parameter) Env1 in <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>Env1>
): <
function (type parameter) OutElem in <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,
function (type parameter) OutDone in <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>OutDone,
function (type parameter) InElem in <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>InElem,
function (type parameter) InErr in <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>InErr,
function (type parameter) InDone in <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>InDone,
function (type parameter) Env in <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>Env
>(self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>
(parameter) self: {
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 Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<function (type parameter) OutElem in <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, function (type parameter) OutErr in <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>OutErr, function (type parameter) OutDone in <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>OutDone, function (type parameter) InElem in <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>InElem, function (type parameter) InErr in <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>InErr, function (type parameter) InDone in <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>InDone, function (type parameter) Env in <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>Env>) => interface Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<
function (type parameter) OutElem in <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 | function (type parameter) OutElem1 in <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>OutElem1,
import CauseCause.declareCause.type Cause.Cause.Error = /*unresolved*/ anyError<function (type parameter) X in <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>X> | function (type parameter) OutErr1 in <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>OutErr1,
function (type parameter) OutDone in <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>OutDone | function (type parameter) OutDone1 in <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>OutDone1,
function (type parameter) InElem in <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>InElem & function (type parameter) InElem1 in <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>InElem1,
function (type parameter) InErr in <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>InErr & function (type parameter) InErr1 in <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>InErr1,
function (type parameter) InDone in <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>InDone & function (type parameter) InDone1 in <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>InDone1,
function (type parameter) Env in <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>Env | function (type parameter) Env1 in <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>Env1
>
<
function (type parameter) OutElem in <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>OutElem,
function (type parameter) OutErr in <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>OutErr,
function (type parameter) OutDone in <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>OutDone,
function (type parameter) InElem in <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>InElem,
function (type parameter) InErr in <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>InErr,
function (type parameter) InDone in <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>InDone,
function (type parameter) Env in <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>Env,
function (type parameter) EB in <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>EB,
function (type parameter) X in <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>X extends import CauseCause.type Cause.Cause = /*unresolved*/ anyCause<any>,
function (type parameter) OutElem1 in <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>OutElem1,
function (type parameter) OutErr1 in <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>OutErr1,
function (type parameter) OutDone1 in <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>OutDone1,
function (type parameter) InElem1 in <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>InElem1,
function (type parameter) InErr1 in <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>InErr1,
function (type parameter) InDone1 in <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>InDone1,
function (type parameter) Env1 in <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>Env1
>(
self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>
(parameter) self: {
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 Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<function (type parameter) OutElem in <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>OutElem, function (type parameter) OutErr in <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>OutErr, function (type parameter) OutDone in <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>OutDone, function (type parameter) InElem in <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>InElem, function (type parameter) InErr in <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>InErr, function (type parameter) InDone in <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>InDone, function (type parameter) Env in <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>Env>,
filter: Filter.Filter<
Cause.Cause<OutErr>,
EB,
X
>
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.type Cause.Cause = /*unresolved*/ anyCause<function (type parameter) OutErr in <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>OutErr>, function (type parameter) EB in <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>EB, function (type parameter) X in <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>X>,
f: (
failure: EB,
cause: Cause.Cause<OutErr>
) => Channel<
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>
failure: EBfailure: function (type parameter) EB in <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>EB,
cause: Cause.Cause<OutErr>(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.type Cause.Cause = /*unresolved*/ anyCause<function (type parameter) OutErr in <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>OutErr>
) => interface Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<function (type parameter) OutElem1 in <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>OutElem1, function (type parameter) OutErr1 in <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>OutErr1, function (type parameter) OutDone1 in <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>OutDone1, function (type parameter) InElem1 in <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>InElem1, function (type parameter) InErr1 in <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>InErr1, function (type parameter) InDone1 in <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>InDone1, function (type parameter) Env1 in <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>Env1>
): interface Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<
function (type parameter) OutElem in <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>OutElem | function (type parameter) OutElem1 in <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>OutElem1,
import CauseCause.declareCause.type Cause.Cause.Error = /*unresolved*/ anyError<function (type parameter) X in <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>X> | function (type parameter) OutErr1 in <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>OutErr1,
function (type parameter) OutDone in <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>OutDone | function (type parameter) OutDone1 in <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>OutDone1,
function (type parameter) InElem in <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>InElem & function (type parameter) InElem1 in <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>InElem1,
function (type parameter) InErr in <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>InErr & function (type parameter) InErr1 in <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>InErr1,
function (type parameter) InDone in <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>InDone & function (type parameter) InDone1 in <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>InDone1,
function (type parameter) Env in <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>Env | function (type parameter) Env1 in <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>Env1
>
} = dual<(...args: Array<any>) => any, <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>>(arity: 3, body: <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>): ((...args: Array<any>) => any) & (<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>) (+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) OutElem in <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>OutElem,
function (type parameter) OutErr in <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>OutErr,
function (type parameter) OutDone in <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>OutDone,
function (type parameter) InElem in <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>InElem,
function (type parameter) InErr in <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>InErr,
function (type parameter) InDone in <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>InDone,
function (type parameter) Env in <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>Env,
function (type parameter) EB in <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>EB,
function (type parameter) X in <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>X extends import CauseCause.type Cause.Cause = /*unresolved*/ anyCause<any>,
function (type parameter) OutElem1 in <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>OutElem1,
function (type parameter) OutErr1 in <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>OutErr1,
function (type parameter) OutDone1 in <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>OutDone1,
function (type parameter) InElem1 in <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>InElem1,
function (type parameter) InErr1 in <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>InErr1,
function (type parameter) InDone1 in <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>InDone1,
function (type parameter) Env1 in <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>Env1
>(
self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>
(parameter) self: {
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 Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<function (type parameter) OutElem in <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>OutElem, function (type parameter) OutErr in <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>OutErr, function (type parameter) OutDone in <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>OutDone, function (type parameter) InElem in <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>InElem, function (type parameter) InErr in <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>InErr, function (type parameter) InDone in <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>InDone, function (type parameter) Env in <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>Env>,
filter: Filter.Filter<
Cause.Cause<OutErr>,
EB,
X
>
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.type Cause.Cause = /*unresolved*/ anyCause<function (type parameter) OutErr in <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>OutErr>, function (type parameter) EB in <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>EB, function (type parameter) X in <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>X>,
f: (
failure: EB,
cause: Cause.Cause<OutErr>
) => Channel<
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>
failure: EBfailure: function (type parameter) EB in <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>EB,
cause: Cause.Cause<OutErr>(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.type Cause.Cause = /*unresolved*/ anyCause<function (type parameter) OutErr in <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>OutErr>
) => interface Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<function (type parameter) OutElem1 in <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>OutElem1, function (type parameter) OutErr1 in <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>OutErr1, function (type parameter) OutDone1 in <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>OutDone1, function (type parameter) InElem1 in <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>InElem1, function (type parameter) InErr1 in <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>InErr1, function (type parameter) InDone1 in <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>InDone1, function (type parameter) Env1 in <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>Env1>
): interface Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<
function (type parameter) OutElem in <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>OutElem | function (type parameter) OutElem1 in <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>OutElem1,
import CauseCause.declareCause.type Cause.Cause.Error = /*unresolved*/ anyError<function (type parameter) X in <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>X> | function (type parameter) OutErr1 in <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>OutErr1,
function (type parameter) OutDone in <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>OutDone | function (type parameter) OutDone1 in <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>OutDone1,
function (type parameter) InElem in <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>InElem & function (type parameter) InElem1 in <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>InElem1,
function (type parameter) InErr in <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>InErr & function (type parameter) InErr1 in <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>InErr1,
function (type parameter) InDone in <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>InDone & function (type parameter) InDone1 in <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>InDone1,
function (type parameter) Env in <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>Env | function (type parameter) Env1 in <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>Env1
> =>
const catchCause: {
<
OutErr,
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>(
f: (
d: 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,
OutErr1,
OutDone | OutDone1,
InElem & InElem1,
InErr & InErr1,
InDone & InDone1,
Env | Env1
>
<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env,
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>(
self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>,
f: (
d: Cause.Cause<OutErr>
) => Channel<
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>
): Channel<
OutElem | OutElem1,
OutErr1,
OutDone | OutDone1,
InElem & InElem1,
InErr & InErr1,
InDone & InDone1,
Env | Env1
>
}
self: Channel<
OutElem,
OutErr,
OutDone,
InElem,
InErr,
InDone,
Env
>
(parameter) self: {
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; <…;
}
cause: Cause.Cause<OutErr>(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;
}
interface Channel<out OutElem, out OutErr = never, out OutDone = void, in InElem = unknown, in InErr = unknown, in InDone = unknown, out Env = never>A Channel is a nexus of I/O operations, which supports both reading and
writing. A channel may read values of type InElem and write values of type
OutElem. When the channel finishes, it yields a value of type OutDone. A
channel may fail with a value of type OutErr.
Details
Channels are the foundation of Streams: both streams and sinks are built on
channels. Most users shouldn't have to use channels directly, as streams and
sinks are much more convenient and cover all common use cases. However, when
adding new stream and sink operators, or doing something highly specialized,
it may be useful to use channels directly.
Channels compose in a variety of ways:
- Piping: One channel can be piped to another channel, assuming the
input type of the second is the same as the output type of the first.
- Sequencing: The terminal value of one channel can be used to create
another channel, and both the first channel and the function that makes
the second channel can be composed into a channel.
- Concatenating: The output of one channel can be used to create other
channels, which are all concatenated together. The first channel and the
function that makes the other channels can be composed into a channel.
Example (Typing channels)
import type { Channel } from "effect"
// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>
// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>
// A channel with all type parameters specified
type FullChannel = Channel.Channel<
string, // OutElem - output elements
Error, // OutErr - output errors
number, // OutDone - completion value
number, // InElem - input elements
string, // InErr - input errors
boolean, // InDone - input completion
{ db: string } // Env - required environment
>
Channel<
function (type parameter) OutElem1 in <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>OutElem1,
import CauseCause.declareCause.type Cause.Cause.Error = /*unresolved*/ anyError<function (type parameter) X in <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>X> | function (type parameter) OutErr1 in <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>OutErr1,
function (type parameter) OutDone1 in <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>OutDone1,
function (type parameter) InElem1 in <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>InElem1,
function (type parameter) InErr1 in <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>InErr1,
function (type parameter) InDone1 in <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>InDone1,
function (type parameter) Env1 in <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>Env1
> => {
const const result: Result.Result<EB, X>result = filter: Filter.Filter<
Cause.Cause<OutErr>,
EB,
X
>
cause: Cause.Cause<OutErr>(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 ResultResult.const isFailure: <A, E>(
self: Result<A, E>
) => self is Failure<A, E>
Checks whether a Result is a Failure.
When to use
Use to narrow a known Result to the Failure variant.
Details
- Acts as a TypeScript type guard, narrowing to
Failure<A, E>
- After narrowing, you can access
.failure to read the error value
Example (Narrowing to failure)
import { Result } from "effect"
const result = Result.fail("oops")
if (Result.isFailure(result)) {
console.log(result.failure)
// Output: "oops"
}
isFailure(const result: Result.Result<EB, X>result)
? const failCause: <E>(
cause: Cause.Cause<E>
) => Channel<never, E, never>
Constructs a channel that fails immediately with the specified Cause.
When to use
Use when the channel failure must preserve a full Cause, such as defects,
interruptions, or combined failures.
Example (Failing with causes)
import { Cause, Channel } from "effect"
// Create a channel that fails with a simple cause
const simpleCause = Cause.fail("Simple error")
const failedChannel = Channel.failCause(simpleCause)
// Create a channel with a die cause
const dieCause = Cause.die(new Error("System error"))
const dieFailure = Channel.failCause(dieCause)
// Create a channel with a simple fail cause
const failCause = Cause.fail("Simple error")
const simpleFail = Channel.failCause(failCause)
failCause(const result: Result.Failure<EB, X>const result: {
_tag: "Failure";
_op: "Failure";
failure: 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;
}
Failure<EB, X>.failure: X extends Cause.Cause<any>failure)
: f: (
failure: EB,
cause: Cause.Cause<OutErr>
) => Channel<
OutElem1,
OutErr1,
OutDone1,
InElem1,
InErr1,
InDone1,
Env1
>
const result: Result.Success<EB, X>const result: {
_tag: "Success";
_op: "Success";
success: A;
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;
}
Success<EB, X>.success: EBsuccess, cause: Cause.Cause<OutErr>(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;
}
Referenced by 1 symbols