<A>(self: Subscription<A>): Effect.Effect<Arr.NonEmptyArray<A>>Takes all available messages from the subscription, suspending if no items are available.
Example (Taking all available messages)
import { Effect, PubSub } from "effect"
const program = Effect.gen(function*() {
const pubsub = yield* PubSub.bounded<string>(10)
yield* Effect.scoped(Effect.gen(function*() {
const subscription = yield* PubSub.subscribe(pubsub)
// Publish multiple messages
yield* PubSub.publishAll(pubsub, ["msg1", "msg2", "msg3"])
// Take all available messages at once
const allMessages = yield* PubSub.takeAll(subscription)
console.log("All messages:", allMessages) // ["msg1", "msg2", "msg3"]
}))
})export const const takeAll: <A>(
self: Subscription<A>
) => Effect.Effect<Arr.NonEmptyArray<A>>
Takes all available messages from the subscription, suspending if no items
are available.
Example (Taking all available messages)
import { Effect, PubSub } from "effect"
const program = Effect.gen(function*() {
const pubsub = yield* PubSub.bounded<string>(10)
yield* Effect.scoped(Effect.gen(function*() {
const subscription = yield* PubSub.subscribe(pubsub)
// Publish multiple messages
yield* PubSub.publishAll(pubsub, ["msg1", "msg2", "msg3"])
// Take all available messages at once
const allMessages = yield* PubSub.takeAll(subscription)
console.log("All messages:", allMessages) // ["msg1", "msg2", "msg3"]
}))
})
takeAll = <function (type parameter) A in <A>(self: Subscription<A>): Effect.Effect<Arr.NonEmptyArray<A>>A>(self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self: interface Subscription<out A>A subscription represents a consumer's connection to a PubSub, allowing them to take messages.
Example (Taking messages from a subscription)
import { Effect, PubSub } from "effect"
const program = Effect.gen(function*() {
const pubsub = yield* PubSub.bounded<string>(10)
// Subscribe within a scope for automatic cleanup
yield* Effect.scoped(Effect.gen(function*() {
const subscription: PubSub.Subscription<string> = yield* PubSub.subscribe(
pubsub
)
yield* PubSub.publishAll(pubsub, ["msg1", "msg2", "msg3"])
// Take individual messages
const message = yield* PubSub.take(subscription)
console.log(message) // "msg1"
// Take multiple messages
const messages = yield* PubSub.takeUpTo(subscription, 1)
console.log(messages) // ["msg2"]
const allMessages = yield* PubSub.takeAll(subscription)
console.log(allMessages) // ["msg3"]
}))
})
Subscription<function (type parameter) A in <A>(self: Subscription<A>): Effect.Effect<Arr.NonEmptyArray<A>>A>): 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<import ArrArr.type NonEmptyArray<A> = [A, ...A[]]A mutable array guaranteed to have at least one element.
When to use
Use when mutation is acceptable and non-emptiness must be tracked at the type
level.
Details
This is the mutable counterpart of
NonEmptyReadonlyArray
. Most Array
module functions return NonEmptyArray when the result is guaranteed
non-empty.
Example (Typing a mutable non-empty array)
import type { Array } from "effect"
const nonEmpty: Array.NonEmptyArray<number> = [1, 2, 3]
nonEmpty.push(4)
NonEmptyArray<function (type parameter) A in <A>(self: Subscription<A>): Effect.Effect<Arr.NonEmptyArray<A>>A>> =>
import EffectEffect.const suspend: <A, E, R>(
effect: LazyArg<Effect<A, E, R>>
) => Effect<A, E, R>
Creates an Effect lazily, delaying construction until it is needed.
When to use
Use when you need to defer the evaluation of an effect until it is required.
Details
suspend takes a thunk that represents an effect and delays creating it
until the suspended effect is evaluated. This is useful for optimizing
expensive computations, managing circular dependencies such as recursive
functions, and helping TypeScript unify return types when branches construct
different effects. Any side effects or scoped captures inside the thunk are
re-executed on each invocation.
Example (Lazily evaluating side effects)
import { Effect } from "effect"
let i = 0
const bad = Effect.succeed(i++)
const good = Effect.suspend(() => Effect.succeed(i++))
console.log(Effect.runSync(bad)) // Output: 0
console.log(Effect.runSync(bad)) // Output: 0
console.log(Effect.runSync(good)) // Output: 1
console.log(Effect.runSync(good)) // Output: 2
Example (Suspending recursive Fibonacci evaluation)
import { Effect } from "effect"
const blowsUp = (n: number): Effect.Effect<number> =>
n < 2
? Effect.succeed(1)
: Effect.zipWith(blowsUp(n - 1), blowsUp(n - 2), (a, b) => a + b)
// console.log(Effect.runSync(blowsUp(32)))
// crash: JavaScript heap out of memory
const allGood = (n: number): Effect.Effect<number> =>
n < 2
? Effect.succeed(1)
: Effect.zipWith(
Effect.suspend(() => allGood(n - 1)),
Effect.suspend(() => allGood(n - 2)),
(a, b) => a + b
)
console.log(Effect.runSync(allGood(32)))
// Output: 3524578
Example (Helping TypeScript infer recursive effect types)
import { Effect } from "effect"
// Without suspend, TypeScript may struggle with type inference.
// Inferred type:
// (a: number, b: number) =>
// Effect<never, Error, never> | Effect<number, never, never>
const withoutSuspend = (a: number, b: number) =>
b === 0
? Effect.fail(new Error("Cannot divide by zero"))
: Effect.succeed(a / b)
// Using suspend to unify return types.
// Inferred type:
// (a: number, b: number) => Effect<number, Error, never>
const withSuspend = (a: number, b: number) =>
Effect.suspend(() =>
b === 0
? Effect.fail(new Error("Cannot divide by zero"))
: Effect.succeed(a / b)
)
suspend(function function (local function) loop(value?: [A]): Effect.Effect<Arr.NonEmptyArray<A>>loop(value: [A] | undefinedvalue?: [function (type parameter) A in <A>(self: Subscription<A>): Effect.Effect<Arr.NonEmptyArray<A>>A]): 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<import ArrArr.type NonEmptyArray<A> = [A, ...A[]]A mutable array guaranteed to have at least one element.
When to use
Use when mutation is acceptable and non-emptiness must be tracked at the type
level.
Details
This is the mutable counterpart of
NonEmptyReadonlyArray
. Most Array
module functions return NonEmptyArray when the result is guaranteed
non-empty.
Example (Typing a mutable non-empty array)
import type { Array } from "effect"
const nonEmpty: Array.NonEmptyArray<number> = [1, 2, 3]
nonEmpty.push(4)
NonEmptyArray<function (type parameter) A in <A>(self: Subscription<A>): Effect.Effect<Arr.NonEmptyArray<A>>A>> {
if (self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self.Subscription<out A>.shutdownFlag: MutableRef.MutableRef<boolean>(property) Subscription<out A>.shutdownFlag: {
current: T;
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;
}
shutdownFlag.MutableRef<boolean>.current: booleancurrent) {
return import EffectEffect.const interrupt: Effect<never>const interrupt: {
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 is immediately interrupted.
Example (Creating an interrupted effect)
import { Effect } from "effect"
const program = Effect.gen(function*() {
return yield* Effect.interrupt
yield* Effect.succeed("This won't execute and is unreachable")
})
Effect.runPromise(program).catch(console.error)
// Throws: InterruptedException
interrupt
}
let let as: A[]as = self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self.Subscription<out A>.pollers: MutableList.MutableList<Deferred.Deferred<any>>(property) Subscription<out A>.pollers: {
head: MutableList.Bucket<A> | undefined;
tail: MutableList.Bucket<A> | undefined;
length: number;
}
pollers.MutableList<Deferred<any, never>>.length: numberlength === 0
? self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self.Subscription<A>.subscription: PubSub.BackingSubscription<A>(property) Subscription<A>.subscription: {
isEmpty: () => boolean;
size: () => number;
poll: () => typeof MutableList.Empty | A;
pollUpTo: (n: number) => Array<A>;
unsubscribe: () => void;
}
subscription.PubSub<in out A>.BackingSubscription<A>.pollUpTo(n: number): A[]pollUpTo(var Number: NumberConstructorAn object that represents a number of any kind. All JavaScript numbers are 64-bit floating-point numbers.
Number.NumberConstructor.POSITIVE_INFINITY: numberA value greater than the largest number that can be represented in JavaScript.
JavaScript displays POSITIVE_INFINITY values as infinity.
POSITIVE_INFINITY)
: []
if (value: [A] | undefinedvalue) {
let as: A[]as = value: [A](parameter) value: {
0: A;
length: 1;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
pop: () => A | undefined;
push: (...items: Array<A>) => number;
concat: { (...items: Array<ConcatArray<A>>): Array<A>; (...items: Array<A | ConcatArray<A>>): Array<A> };
join: (separator?: string) => string;
reverse: () => Array<A>;
shift: () => A | undefined;
slice: (start?: number, end?: number) => Array<A>;
sort: (compareFn?: ((a: A, b: A) => number) | undefined) => [A];
splice: { (start: number, deleteCount?: number): Array<A>; (start: number, deleteCount: number, ...items: Array<A>): Array<A> };
unshift: (...items: Array<A>) => number;
indexOf: (searchElement: A, fromIndex?: number) => number;
lastIndexOf: (searchElement: A, fromIndex?: number) => number;
every: { (predicate: (value: A, index: number, array: Array<A>) => value is S, thisArg?: any): this is S[]; (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: A, index: number, array: Array<A>) => void, thisArg?: any) => void;
map: (callbackfn: (value: A, index: number, array: Array<A>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: A, index: number, array: Array<A>) => value is S, thisArg?: any): Array<S>; (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any): Array<A> };
reduce: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: Array<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: Array<A>) => A, initialValue: A): A; (callbackfn: (previousVa…;
reduceRight: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: Array<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: Array<A>) => A, initialValue: A): A; (callbackfn: (previousVa…;
find: { (predicate: (value: A, index: number, obj: Array<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, obj: Array<A>) => unknown, thisArg?: any): A | undefined };
findIndex: (predicate: (value: A, index: number, obj: Array<A>) => unknown, thisArg?: any) => number;
fill: (value: A, start?: number, end?: number) => [A];
copyWithin: (target: number, start: number, end?: number) => [A];
entries: () => ArrayIterator<[number, A]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<A>;
includes: (searchElement: A, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: A, index: number, array: Array<A>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => A | undefined;
findLast: { (predicate: (value: A, index: number, array: Array<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any): A | undefined };
findLastIndex: (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any) => number;
toReversed: () => Array<A>;
toSorted: (compareFn?: ((a: A, b: A) => number) | undefined) => Array<A>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<A>): Array<A>; (start: number, deleteCount?: number): Array<A> };
with: (index: number, value: A) => Array<A>;
}
value.Array<A>.concat(...items: ConcatArray<A>[]): A[] (+1 overload)Combines two or more arrays.
This method returns a new array without modifying any existing arrays.
concat(let as: A[]as)
}
self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self.Subscription<out A>.strategy: PubSub.Strategy<any>(property) Subscription<out A>.strategy: {
shutdown: Effect.Effect<void>;
handleSurplus: (pubsub: PubSub.Atomic<any>, subscribers: PubSub.Subscribers<any>, elements: Iterable<any>, isShutdown: MutableRef.MutableRef<boolean>) => Effect.Effect<boolean>;
onPubSubEmptySpaceUnsafe: (pubsub: PubSub.Atomic<any>, subscribers: PubSub.Subscribers<any>) => void;
completePollersUnsafe: (pubsub: PubSub.Atomic<any>, subscribers: PubSub.Subscribers<any>, subscription: PubSub.BackingSubscription<any>, pollers: MutableList.MutableList<Deferred.Deferred<any, never>>) => void;
completeSubscribersUnsafe: (pubsub: PubSub.Atomic<any>, subscribers: PubSub.Subscribers<any>) => void;
}
strategy.PubSub<in out A>.Strategy<any>.onPubSubEmptySpaceUnsafe(pubsub: PubSub<in out A>.Atomic<any>, subscribers: PubSub.Subscribers<any>): voidDescribes how subscribers should signal to publishers waiting for space
to become available in the PubSub that space may be available.
onPubSubEmptySpaceUnsafe(self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self.Subscription<out A>.pubsub: PubSub.Atomic<any>(property) Subscription<out A>.pubsub: {
capacity: number;
isEmpty: () => boolean;
isFull: () => boolean;
size: () => number;
publish: (value: any) => boolean;
publishAll: (elements: Iterable<any>) => Array<any>;
slide: () => void;
subscribe: () => PubSub.BackingSubscription<any>;
replayWindow: () => PubSub.ReplayWindow<any>;
}
pubsub, self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self.Subscription<out A>.subscribers: PubSub.Subscribers<any>(property) Subscription<out A>.subscribers: {
clear: () => void;
delete: (key: PubSub.BackingSubscription<any>) => boolean;
forEach: (callbackfn: (value: Set<MutableList.MutableList<Deferred.Deferred<any, never>>>, key: PubSub.BackingSubscription<any>, map: Map<PubSub.BackingSubscription<any>, Set<MutableList.MutableList<Deferred.Deferred<any, never>>>>) => void, thisAr…;
get: (key: PubSub.BackingSubscription<any>) => Set<MutableList.MutableList<Deferred.Deferred<any, never>>> | undefined;
has: (key: PubSub.BackingSubscription<any>) => boolean;
set: (key: PubSub.BackingSubscription<any>, value: Set<MutableList.MutableList<Deferred.Deferred<any, never>>>) => PubSub.Subscribers<any>;
size: number;
entries: () => MapIterator<[PubSub.BackingSubscription<any>, Set<MutableList.MutableList<Deferred.Deferred<any, never>>>]>;
keys: () => MapIterator<PubSub.BackingSubscription<any>>;
values: () => MapIterator<Set<MutableList.MutableList<Deferred.Deferred<any, never>>>>;
}
subscribers)
if (self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self.Subscription<A>.replayWindow: PubSub.ReplayWindow<A>(property) Subscription<A>.replayWindow: {
take: () => A | undefined;
takeN: (n: number) => Array<A>;
takeAll: () => Array<A>;
remaining: number;
}
replayWindow.PubSub<in out A>.ReplayWindow<A>.remaining: numberremaining > 0) {
return import EffectEffect.const succeed: <A>(value: A) => Effect<A>Creates an Effect that always succeeds with a given value.
When to use
Use when an effect should complete successfully with a specific value without any errors
or external dependencies.
Example (Creating a successful effect)
import { Effect } from "effect"
// Creating an effect that represents a successful scenario
//
// ┌─── Effect<number, never, never>
// ▼
const success = Effect.succeed(42)
succeed(self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self.Subscription<A>.replayWindow: PubSub.ReplayWindow<A>(property) Subscription<A>.replayWindow: {
take: () => A | undefined;
takeN: (n: number) => Array<A>;
takeAll: () => Array<A>;
remaining: number;
}
replayWindow.PubSub<in out A>.ReplayWindow<A>.takeAll(): A[]takeAll().Array<A>.concat(...items: ConcatArray<A>[]): A[] (+1 overload)Combines two or more arrays.
This method returns a new array without modifying any existing arrays.
concat(let as: A[]as) as import ArrArr.type NonEmptyArray<A> = [A, ...A[]]A mutable array guaranteed to have at least one element.
When to use
Use when mutation is acceptable and non-emptiness must be tracked at the type
level.
Details
This is the mutable counterpart of
NonEmptyReadonlyArray
. Most Array
module functions return NonEmptyArray when the result is guaranteed
non-empty.
Example (Typing a mutable non-empty array)
import type { Array } from "effect"
const nonEmpty: Array.NonEmptyArray<number> = [1, 2, 3]
nonEmpty.push(4)
NonEmptyArray<function (type parameter) A in <A>(self: Subscription<A>): Effect.Effect<Arr.NonEmptyArray<A>>A>)
} else if (!import ArrArr.const isArrayNonEmpty: <A>(
self: Array<A>
) => self is NonEmptyArray<A>
Checks whether a mutable Array is non-empty, narrowing the type to
NonEmptyArray.
When to use
Use when you need the narrowed value to remain a mutable Array after proving
it has at least one element.
Example (Checking for a non-empty array)
import { Array } from "effect"
console.log(Array.isArrayNonEmpty([])) // false
console.log(Array.isArrayNonEmpty([1, 2, 3])) // true
isArrayNonEmpty(let as: A[]as)) {
return 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>
}
flatMap(const pollForItem: <A>(
self: Subscription<A>
) => Effect.Effect<A, never, never>
pollForItem(self: Subscription<A>(parameter) self: {
pubsub: PubSub.Atomic<any>;
subscribers: PubSub.Subscribers<any>;
subscription: PubSub.BackingSubscription<A>;
pollers: MutableList.MutableList<Deferred.Deferred<any>>;
shutdownHook: Latch.Latch;
shutdownFlag: MutableRef.MutableRef<boolean>;
strategy: PubSub.Strategy<any>;
replayWindow: PubSub.ReplayWindow<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; <…;
}
self), (item: Aitem) => function (local function) loop(value?: [A]): Effect.Effect<Arr.NonEmptyArray<A>>loop([item: Aitem]))
}
return import EffectEffect.const succeed: <A>(value: A) => Effect<A>Creates an Effect that always succeeds with a given value.
When to use
Use when an effect should complete successfully with a specific value without any errors
or external dependencies.
Example (Creating a successful effect)
import { Effect } from "effect"
// Creating an effect that represents a successful scenario
//
// ┌─── Effect<number, never, never>
// ▼
const success = Effect.succeed(42)
succeed(let as: [A, ...A[]]let as: {
0: A;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
pop: () => A | undefined;
push: (...items: Array<A>) => number;
concat: { (...items: Array<ConcatArray<A>>): Array<A>; (...items: Array<A | ConcatArray<A>>): Array<A> };
join: (separator?: string) => string;
reverse: () => Array<A>;
shift: () => A | undefined;
slice: (start?: number, end?: number) => Array<A>;
sort: (compareFn?: ((a: A, b: A) => number) | undefined) => [A, ...A[]];
splice: { (start: number, deleteCount?: number): Array<A>; (start: number, deleteCount: number, ...items: Array<A>): Array<A> };
unshift: (...items: Array<A>) => number;
indexOf: (searchElement: A, fromIndex?: number) => number;
lastIndexOf: (searchElement: A, fromIndex?: number) => number;
every: { (predicate: (value: A, index: number, array: Array<A>) => value is S, thisArg?: any): this is S[]; (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: A, index: number, array: Array<A>) => void, thisArg?: any) => void;
map: (callbackfn: (value: A, index: number, array: Array<A>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: A, index: number, array: Array<A>) => value is S, thisArg?: any): Array<S>; (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any): Array<A> };
reduce: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: Array<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: Array<A>) => A, initialValue: A): A; (callbackfn: (previousVa…;
reduceRight: { (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: Array<A>) => A): A; (callbackfn: (previousValue: A, currentValue: A, currentIndex: number, array: Array<A>) => A, initialValue: A): A; (callbackfn: (previousVa…;
find: { (predicate: (value: A, index: number, obj: Array<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, obj: Array<A>) => unknown, thisArg?: any): A | undefined };
findIndex: (predicate: (value: A, index: number, obj: Array<A>) => unknown, thisArg?: any) => number;
fill: (value: A, start?: number, end?: number) => [A, ...A[]];
copyWithin: (target: number, start: number, end?: number) => [A, ...A[]];
entries: () => ArrayIterator<[number, A]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<A>;
includes: (searchElement: A, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: A, index: number, array: Array<A>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => A | undefined;
findLast: { (predicate: (value: A, index: number, array: Array<A>) => value is S, thisArg?: any): S | undefined; (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any): A | undefined };
findLastIndex: (predicate: (value: A, index: number, array: Array<A>) => unknown, thisArg?: any) => number;
toReversed: () => Array<A>;
toSorted: (compareFn?: ((a: A, b: A) => number) | undefined) => Array<A>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<A>): Array<A>; (start: number, deleteCount?: number): Array<A> };
with: (index: number, value: A) => Array<A>;
}
as)
})