<OutElem, OutErr>(queue: Queue.Queue<OutElem, OutErr | Cause.Done>): <
OutDone,
Env
>(
self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>
) => Effect.Effect<void, never, Env>
<OutElem, OutErr, OutDone, Env>(
self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>,
queue: Queue.Queue<OutElem, OutErr | Cause.Done>
): Effect.Effect<void, never, Env>Runs a channel and offers each output element into a queue.
Details
When the channel completes, the queue is ended. When the channel fails, the
queue is failed with the channel's cause. The returned effect itself
completes with void.
export const const runIntoQueue: {
<OutElem, OutErr>(
queue: Queue.Queue<
OutElem,
OutErr | Cause.Done
>
): <OutDone, Env>(
self: Channel<
OutElem,
OutErr,
OutDone,
unknown,
unknown,
unknown,
Env
>
) => Effect.Effect<void, never, Env>
<OutElem, OutErr, OutDone, Env>(
self: Channel<
OutElem,
OutErr,
OutDone,
unknown,
unknown,
unknown,
Env
>,
queue: Queue.Queue<
OutElem,
OutErr | Cause.Done
>
): Effect.Effect<void, never, Env>
}
Runs a channel and offers each output element into a queue.
Details
When the channel completes, the queue is ended. When the channel fails, the
queue is failed with the channel's cause. The returned effect itself
completes with void.
runIntoQueue: {
<function (type parameter) OutElem in <OutElem, OutErr>(queue: Queue.Queue<OutElem, OutErr | Cause.Done>): <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>) => Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr>(queue: Queue.Queue<OutElem, OutErr | Cause.Done>): <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>) => Effect.Effect<void, never, Env>OutErr>(queue: Queue.Queue<
OutElem,
OutErr | Cause.Done
>
(parameter) queue: {
strategy: "suspend" | "dropping" | "sliding";
dispatcher: SchedulerDispatcher;
capacity: number;
messages: MutableList.MutableList<any>;
state: Queue.State<any, any>;
scheduleRunning: boolean;
toString: () => string;
toJSON: () => unknown;
}
import QueueQueue.interface Queue<in out A, in out E = never>A Queue is an asynchronous queue that can be offered to and taken from.
Details
It also supports signaling that it is done or failed.
Example (Offering and taking queue values)
import { Effect, Queue } from "effect"
const program = Effect.gen(function*() {
// Create a bounded queue
const queue = yield* Queue.bounded<string>(10)
// Producer: offer items to the queue
yield* Queue.offer(queue, "hello")
yield* Queue.offerAll(queue, ["world", "!"])
// Consumer: take items from the queue
const item1 = yield* Queue.take(queue)
const item2 = yield* Queue.take(queue)
const item3 = yield* Queue.take(queue)
console.log([item1, item2, item3]) // ["hello", "world", "!"]
})
Companion namespace containing type-level metadata and low-level state types
for Queue.
Queue<function (type parameter) OutElem in <OutElem, OutErr>(queue: Queue.Queue<OutElem, OutErr | Cause.Done>): <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>) => Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr>(queue: Queue.Queue<OutElem, OutErr | Cause.Done>): <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>) => Effect.Effect<void, never, Env>OutErr | import CauseCause.type Cause.Done = /*unresolved*/ anyDone>): <function (type parameter) OutDone in <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>): Effect.Effect<void, never, Env>OutDone, function (type parameter) Env in <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>): Effect.Effect<void, never, Env>Env>(
self: Channel<
OutElem,
OutErr,
OutDone,
unknown,
unknown,
unknown,
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>(queue: Queue.Queue<OutElem, OutErr | Cause.Done>): <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>) => Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr>(queue: Queue.Queue<OutElem, OutErr | Cause.Done>): <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>) => Effect.Effect<void, never, Env>OutErr, function (type parameter) OutDone in <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>): Effect.Effect<void, never, Env>OutDone, unknown, unknown, unknown, function (type parameter) Env in <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>): Effect.Effect<void, never, Env>Env>
) => import EffectEffect.interface Effect<out A, out E = never, out R = never>The Effect interface defines a value that lazily describes a workflow or
job. The workflow requires some context R, and may fail with an error of
type E, or succeed with a value of type A.
When to use
Use when you need to represent a lazy, composable workflow that can require
services, fail with a typed error, or succeed with a typed value.
Details
Effect values model resourceful interaction with the outside world,
including synchronous, asynchronous, concurrent, and parallel interaction.
They use a fiber-based concurrency model, with built-in support for
scheduling, fine-grained interruption, structured concurrency, and high
scalability.
To run an Effect value, you need a Runtime, which is a type that is
capable of executing Effect values.
Effect<void, never, function (type parameter) Env in <OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>): Effect.Effect<void, never, Env>Env>
<function (type parameter) OutElem in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutErr, function (type parameter) OutDone in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutDone, function (type parameter) Env in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>Env>(
self: Channel<
OutElem,
OutErr,
OutDone,
unknown,
unknown,
unknown,
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, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutErr, function (type parameter) OutDone in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutDone, unknown, unknown, unknown, function (type parameter) Env in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>Env>,
queue: Queue.Queue<
OutElem,
OutErr | Cause.Done
>
(parameter) queue: {
strategy: "suspend" | "dropping" | "sliding";
dispatcher: SchedulerDispatcher;
capacity: number;
messages: MutableList.MutableList<any>;
state: Queue.State<any, any>;
scheduleRunning: boolean;
toString: () => string;
toJSON: () => unknown;
}
import QueueQueue.interface Queue<in out A, in out E = never>A Queue is an asynchronous queue that can be offered to and taken from.
Details
It also supports signaling that it is done or failed.
Example (Offering and taking queue values)
import { Effect, Queue } from "effect"
const program = Effect.gen(function*() {
// Create a bounded queue
const queue = yield* Queue.bounded<string>(10)
// Producer: offer items to the queue
yield* Queue.offer(queue, "hello")
yield* Queue.offerAll(queue, ["world", "!"])
// Consumer: take items from the queue
const item1 = yield* Queue.take(queue)
const item2 = yield* Queue.take(queue)
const item3 = yield* Queue.take(queue)
console.log([item1, item2, item3]) // ["hello", "world", "!"]
})
Companion namespace containing type-level metadata and low-level state types
for Queue.
Queue<function (type parameter) OutElem in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutErr | import CauseCause.type Cause.Done = /*unresolved*/ anyDone>
): import EffectEffect.interface Effect<out A, out E = never, out R = never>The Effect interface defines a value that lazily describes a workflow or
job. The workflow requires some context R, and may fail with an error of
type E, or succeed with a value of type A.
When to use
Use when you need to represent a lazy, composable workflow that can require
services, fail with a typed error, or succeed with a typed value.
Details
Effect values model resourceful interaction with the outside world,
including synchronous, asynchronous, concurrent, and parallel interaction.
They use a fiber-based concurrency model, with built-in support for
scheduling, fine-grained interruption, structured concurrency, and high
scalability.
To run an Effect value, you need a Runtime, which is a type that is
capable of executing Effect values.
Effect<void, never, function (type parameter) Env in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>Env>
} = dual<(...args: Array<any>) => any, <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>) => Effect.Effect<void, never, Env>>(isDataFirst: (args: IArguments) => boolean, body: <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>) => Effect.Effect<void, never, Env>): ((...args: Array<any>) => any) & (<OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>) => Effect.Effect<void, never, Env>) (+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(
(args: IArgumentsargs) => const isChannel: (
u: unknown
) => u is Channel<
unknown,
unknown,
unknown,
unknown,
unknown,
unknown,
unknown
>
Checks whether a value is a Channel.
Example (Checking for channels)
import { Channel } from "effect"
const channel = Channel.succeed(42)
console.log(Channel.isChannel(channel)) // true
console.log(Channel.isChannel("not a channel")) // false
isChannel(args: IArgumentsargs[0]),
<function (type parameter) OutElem in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutErr, function (type parameter) OutDone in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutDone, function (type parameter) Env in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>Env>(
self: Channel<
OutElem,
OutErr,
OutDone,
unknown,
unknown,
unknown,
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, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutErr, function (type parameter) OutDone in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutDone, unknown, unknown, unknown, function (type parameter) Env in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>Env>,
queue: Queue.Queue<
OutElem,
OutErr | Cause.Done
>
(parameter) queue: {
strategy: "suspend" | "dropping" | "sliding";
dispatcher: SchedulerDispatcher;
capacity: number;
messages: MutableList.MutableList<any>;
state: Queue.State<any, any>;
scheduleRunning: boolean;
toString: () => string;
toJSON: () => unknown;
}
import QueueQueue.interface Queue<in out A, in out E = never>A Queue is an asynchronous queue that can be offered to and taken from.
Details
It also supports signaling that it is done or failed.
Example (Offering and taking queue values)
import { Effect, Queue } from "effect"
const program = Effect.gen(function*() {
// Create a bounded queue
const queue = yield* Queue.bounded<string>(10)
// Producer: offer items to the queue
yield* Queue.offer(queue, "hello")
yield* Queue.offerAll(queue, ["world", "!"])
// Consumer: take items from the queue
const item1 = yield* Queue.take(queue)
const item2 = yield* Queue.take(queue)
const item3 = yield* Queue.take(queue)
console.log([item1, item2, item3]) // ["hello", "world", "!"]
})
Companion namespace containing type-level metadata and low-level state types
for Queue.
Queue<function (type parameter) OutElem in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutElem, function (type parameter) OutErr in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>OutErr | import CauseCause.type Cause.Done = /*unresolved*/ anyDone>
): import EffectEffect.interface Effect<out A, out E = never, out R = never>The Effect interface defines a value that lazily describes a workflow or
job. The workflow requires some context R, and may fail with an error of
type E, or succeed with a value of type A.
When to use
Use when you need to represent a lazy, composable workflow that can require
services, fail with a typed error, or succeed with a typed value.
Details
Effect values model resourceful interaction with the outside world,
including synchronous, asynchronous, concurrent, and parallel interaction.
They use a fiber-based concurrency model, with built-in support for
scheduling, fine-grained interruption, structured concurrency, and high
scalability.
To run an Effect value, you need a Runtime, which is a type that is
capable of executing Effect values.
Effect<void, never, function (type parameter) Env in <OutElem, OutErr, OutDone, Env>(self: Channel<OutElem, OutErr, OutDone, unknown, unknown, unknown, Env>, queue: Queue.Queue<OutElem, OutErr | Cause.Done>): Effect.Effect<void, never, Env>Env> =>
import EffectEffect.const uninterruptibleMask: <A, E, R>(
f: (
restore: <AX, EX, RX>(
effect: Effect<AX, EX, RX>
) => Effect<AX, EX, RX>
) => Effect<A, E, R>
) => Effect<A, E, R>
Disables interruption and provides a restore function to restore the
interruptible state within the effect.
Example (Restoring interruption in protected regions)
import { Console, Effect } from "effect"
const program = Effect.uninterruptibleMask((restore) =>
Effect.gen(function*() {
yield* Console.log("Uninterruptible phase...")
yield* Effect.sleep("1 second")
// Restore interruptibility for this part
yield* restore(
Effect.gen(function*() {
yield* Console.log("Interruptible phase...")
yield* Effect.sleep("2 seconds")
})
)
yield* Console.log("Back to uninterruptible")
})
)
uninterruptibleMask((restore: <AX, EX, RX>(
effect: Effect<AX, EX, RX>
) => Effect<AX, EX, RX>
const runForEach: {
<OutElem, EX, RX>(
f: (o: OutElem) => Effect.Effect<void, EX, RX>
): <OutErr, OutDone, Env>(
self: Channel<
OutElem,
OutErr,
OutDone,
unknown,
unknown,
unknown,
Env
>
) => Effect.Effect<
OutDone,
OutErr | EX,
Env | RX
>
<OutElem, OutErr, OutDone, Env, EX, RX>(
self: Channel<
OutElem,
OutErr,
OutDone,
unknown,
unknown,
unknown,
Env
>,
f: (o: OutElem) => Effect.Effect<void, EX, RX>
): Effect.Effect<OutDone, OutErr | EX, Env | RX>
}
self: Channel<
OutElem,
OutErr,
OutDone,
unknown,
unknown,
unknown,
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; <…;
}
value: OutElemvalue) => import QueueQueue.const offer: <A, E>(
self: Enqueue<A, E>,
message: Types.NoInfer<A>
) => Effect<boolean>
Adds a message to the queue. Returns false if the queue is done.
Details
For bounded queues, this operation may suspend if the queue is at capacity,
depending on the backpressure strategy. For dropping/sliding queues, it may
return false or succeed immediately by dropping/sliding existing messages.
Example (Offering a value)
import { Effect, Queue } from "effect"
const program = Effect.gen(function*() {
const queue = yield* Queue.bounded<number>(3)
// Successfully add messages to queue
const success1 = yield* Queue.offer(queue, 1)
const success2 = yield* Queue.offer(queue, 2)
console.log(success1, success2) // true, true
// Queue state
const size = yield* Queue.size(queue)
console.log(size) // 2
})
offer(queue: Queue.Queue<
OutElem,
OutErr | Cause.Done
>
(parameter) queue: {
strategy: "suspend" | "dropping" | "sliding";
dispatcher: SchedulerDispatcher;
capacity: number;
messages: MutableList.MutableList<any>;
state: Queue.State<any, any>;
scheduleRunning: boolean;
toString: () => string;
toJSON: () => unknown;
}
value: OutElemvalue)).Pipeable.pipe<Effect.Effect<OutDone, OutErr, Env>, Effect.Effect<OutDone, OutErr, Env>, Effect.Effect<Exit.Exit<OutDone, OutErr>, never, Env>, Effect.Effect<void, never, Env>>(this: Effect.Effect<...>, ab: (_: Effect.Effect<OutDone, OutErr, Env>) => Effect.Effect<OutDone, OutErr, Env>, bc: (_: Effect.Effect<OutDone, OutErr, Env>) => Effect.Effect<Exit.Exit<OutDone, OutErr>, never, Env>, cd: (_: Effect.Effect<...>) => Effect.Effect<...>): Effect.Effect<...> (+21 overloads)pipe(
restore: <AX, EX, RX>(
effect: Effect<AX, EX, RX>
) => Effect<AX, EX, RX>
import EffectEffect.const exit: <A, E, R>(
self: Effect<A, E, R>
) => Effect<Exit.Exit<A, E>, never, R>
Transforms an effect to encapsulate both failure and success using the Exit
data type.
When to use
Use when you need to inspect the full outcome, including typed failures, defects,
and interruptions.
Details
exit wraps an effect's success or failure inside an Exit type, allowing
you to handle both cases explicitly.
The resulting effect cannot fail because the failure is encapsulated within
the Exit.Failure type. The error type is set to never, indicating that
the effect is structured to never fail directly.
Example (Capturing completion as Exit)
import { Effect } from "effect"
const success = Effect.succeed(42)
const failure = Effect.fail("Something went wrong")
const program1 = Effect.exit(success)
const program2 = Effect.exit(failure)
Effect.runPromise(program1).then(console.log)
// { _id: 'Exit', _tag: 'Success', value: 42 }
Effect.runPromise(program2).then(console.log)
// { _id: 'Exit', _tag: 'Failure', cause: { _id: 'Cause', _tag: 'Fail', failure: 'Something went wrong' } }
exit,
import EffectEffect.const flatMap: {
<A, B, E1, R1>(
f: (a: A) => Effect<B, E1, R1>
): <E, R>(
self: Effect<A, E, R>
) => Effect<B, E1 | E, R1 | R>
<A, E, R, B, E1, R1>(
self: Effect<A, E, R>,
f: (a: A) => Effect<B, E1, R1>
): Effect<B, E | E1, R | R1>
}
exit: Exit.Exit<OutDone, OutErr>exit) => {
if (import ExitExit.const isSuccess: <A, E>(
self: Exit<A, E>
) => self is Success<A, E>
Checks whether an Exit is a Success.
When to use
Use as a type guard to narrow Exit<A, E> to Success<A, E> and access the
value property.
Example (Narrowing to success)
import { Exit } from "effect"
const exit = Exit.succeed(42)
if (Exit.isSuccess(exit)) {
console.log(exit.value) // 42
}
isSuccess(exit: Exit.Exit<OutDone, OutErr>exit)) {
import QueueQueue.const endUnsafe: <A, E>(
self: Enqueue<A, E | Done>
) => boolean
Signals queue completion synchronously.
When to use
Use when implementing low-level queue integrations that must complete a queue
without wrapping the operation in Effect.
Details
Returns false if the queue is already done.
Gotchas
This is an unsafe operation that directly modifies the queue without Effect wrapping.
Example (Ending queues synchronously)
import { Cause, Effect, Queue } from "effect"
// Create a queue and use unsafe operations
const program = Effect.gen(function*() {
const queue = yield* Queue.bounded<number, Cause.Done>(10)
// Add some messages
Queue.offerUnsafe(queue, 1)
Queue.offerUnsafe(queue, 2)
// End the queue synchronously
const ended = Queue.endUnsafe(queue)
console.log(ended) // true
// Existing messages can still be consumed while the queue is closing
console.log(queue.state._tag) // "Closing"
Queue.takeUnsafe(queue)
Queue.takeUnsafe(queue)
// After buffered messages are consumed, the queue is done
console.log(queue.state._tag) // "Done"
})
endUnsafe(queue: Queue.Queue<
OutElem,
OutErr | Cause.Done
>
(parameter) queue: {
strategy: "suspend" | "dropping" | "sliding";
dispatcher: SchedulerDispatcher;
capacity: number;
messages: MutableList.MutableList<any>;
state: Queue.State<any, any>;
scheduleRunning: boolean;
toString: () => string;
toJSON: () => unknown;
}
import QueueQueue.const failCauseUnsafe: <A, E>(
self: Enqueue<A, E>,
cause: Cause<E>
) => boolean
Fails the queue with a cause synchronously. If the queue is already done, false is
returned.
When to use
Use when queue completion must be driven from synchronous internals while
preserving the full failure Cause.
Gotchas
This is an unsafe operation that directly modifies the queue without Effect wrapping.
Example (Failing queues with a cause synchronously)
import { Cause, Effect, Queue } from "effect"
const program = Effect.gen(function*() {
const queue = yield* Queue.bounded<number, string>(10)
// Create a cause and fail the queue synchronously
const cause = Cause.fail("Processing error")
const failed = Queue.failCauseUnsafe(queue, cause)
console.log(failed) // true
// The queue is now done with the specified failure cause
console.log(queue.state._tag) // "Done"
})
failCauseUnsafe(queue: Queue.Queue<
OutElem,
OutErr | Cause.Done
>
(parameter) queue: {
strategy: "suspend" | "dropping" | "sliding";
dispatcher: SchedulerDispatcher;
capacity: number;
messages: MutableList.MutableList<any>;
state: Queue.State<any, any>;
scheduleRunning: boolean;
toString: () => string;
toJSON: () => unknown;
}
exit: Exit.Failure<OutDone, OutErr>(parameter) exit: {
_tag: "Failure";
cause: Cause.Cause<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<out A, out E>.cause: Cause.Cause<E>(property) Failure<out A, out E>.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 EffectEffect.const void: Effect.Effect<void, never, never>(alias) const void: {
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;
}
Returns an effect that succeeds with void.
void
})
)
)
)