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effect

Fiber.ts overview

Since v2.0.0

Exports Grouped by Category

alternatives

orElse

Returns a fiber that prefers this fiber, but falls back to the that one when this one fails. Interrupting the returned fiber will interrupt both fibers, sequentially, from left to right.

Signature

declare const orElse: {
  <A2, E2>(that: Fiber<A2, E2>): <A, E>(self: Fiber<A, E>) => Fiber<A2 | A, E2 | E>
  <A, E, A2, E2>(self: Fiber<A, E>, that: Fiber<A2, E2>): Fiber<A | A2, E | E2>
}

Source

Since v2.0.0

orElseEither

Returns a fiber that prefers this fiber, but falls back to the that one when this one fails. Interrupting the returned fiber will interrupt both fibers, sequentially, from left to right.

Signature

declare const orElseEither: {
  <A2, E2>(that: Fiber<A2, E2>): <A, E>(self: Fiber<A, E>) => Fiber<Either.Either<A2, A>, E2 | E>
  <A, E, A2, E2>(self: Fiber<A, E>, that: Fiber<A2, E2>): Fiber<Either.Either<A2, A>, E | E2>
}

Source

Since v2.0.0

constructors

all

Collects all fibers into a single fiber producing an in-order list of the results.

Signature

declare const all: <A, E>(fibers: Iterable<Fiber<A, E>>) => Fiber<ReadonlyArray<A>, E>

Source

Since v2.0.0

done

A fiber that is done with the specified Exit value.

Signature

declare const done: <A, E>(exit: Exit.Exit<A, E>) => Fiber<A, E>

Source

Since v2.0.0

fail

A fiber that has already failed with the specified value.

Signature

declare const fail: <E>(error: E) => Fiber<never, E>

Source

Since v2.0.0

failCause

Creates a Fiber that has already failed with the specified cause.

Signature

declare const failCause: <E>(cause: Cause.Cause<E>) => Fiber<never, E>

Source

Since v2.0.0

interrupted

Constructrs a Fiber that is already interrupted.

Signature

declare const interrupted: (fiberId: FiberId.FiberId) => Fiber<never>

Source

Since v2.0.0

never

A fiber that never fails or succeeds.

Signature

declare const never: Fiber<never, never>

Source

Since v2.0.0

roots

Returns a chunk containing all root fibers.

Signature

declare const roots: Effect.Effect<Array<RuntimeFiber<any, any>>, never, never>

Source

Since v2.0.0

succeed

Returns a fiber that has already succeeded with the specified value.

Signature

declare const succeed: <A>(value: A) => Fiber<A>

Source

Since v2.0.0

unsafeRoots

Returns a chunk containing all root fibers.

Signature

declare const unsafeRoots: (_: void) => Array<RuntimeFiber<any, any>>

Source

Since v2.0.0

void

A fiber that has already succeeded with unit.

Signature

declare const void: Fiber<void, never>

Source

Since v2.0.0

conversions

fromEffect

Lifts an Effect into a Fiber.

Signature

declare const fromEffect: <A, E>(effect: Effect.Effect<A, E>) => Effect.Effect<Fiber<A, E>>

Source

Since v2.0.0

destructors

awaitAll

Awaits on all fibers to be completed, successfully or not.

Signature

declare const awaitAll: <const T extends Iterable<Fiber<any, any>>>(
  fibers: T
) => Effect.Effect<
  [T] extends [ReadonlyArray<infer U>]
    ? number extends T["length"]
      ? Array<U extends Fiber<infer A, infer E> ? Exit.Exit<A, E> : never>
      : { -readonly [K in keyof T]: T[K] extends Fiber<infer A, infer E> ? Exit.Exit<A, E> : never }
    : Array<T extends Iterable<infer U> ? (U extends Fiber<infer A, infer E> ? Exit.Exit<A, E> : never) : never>
>

Source

Since v2.0.0

dump

Signature

declare const dump: <A, E>(self: RuntimeFiber<A, E>) => Effect.Effect<Fiber.Dump>

Source

Since v2.0.0

dumpAll

Signature

declare const dumpAll: (fibers: Iterable<RuntimeFiber<unknown, unknown>>) => Effect.Effect<Array<Fiber.Dump>>

Source

Since v2.0.0

inheritAll

Inherits values from all FiberRef instances into current fiber. This will resume immediately.

Signature

declare const inheritAll: <A, E>(self: Fiber<A, E>) => Effect.Effect<void>

Source

Since v2.0.0

join

Joins the fiber, which suspends the joining fiber until the result of the fiber has been determined. Attempting to join a fiber that has erred will result in a catchable error. Joining an interrupted fiber will result in an “inner interruption” of this fiber, unlike interruption triggered by another fiber, “inner interruption” can be caught and recovered.

Signature

declare const join: <A, E>(self: Fiber<A, E>) => Effect.Effect<A, E>

Source

Since v2.0.0

joinAll

Joins all fibers, awaiting their successful completion. Attempting to join a fiber that has erred will result in a catchable error, if that error does not result from interruption.

Signature

declare const joinAll: <A, E>(fibers: Iterable<Fiber<A, E>>) => Effect.Effect<Array<A>, E>

Source

Since v2.0.0

pretty

Pretty-prints a RuntimeFiber.

Signature

declare const pretty: <A, E>(self: RuntimeFiber<A, E>) => Effect.Effect<string>

Source

Since v2.0.0

scoped

Converts this fiber into a scoped effect. The fiber is interrupted when the scope is closed.

Signature

declare const scoped: <A, E>(self: Fiber<A, E>) => Effect.Effect<Fiber<A, E>, never, Scope.Scope>

Source

Since v2.0.0

folding

match

Folds over the Fiber or RuntimeFiber.

Signature

declare const match: {
  <A, E, Z>(options: {
    readonly onFiber: (fiber: Fiber<A, E>) => Z
    readonly onRuntimeFiber: (fiber: RuntimeFiber<A, E>) => Z
  }): (self: Fiber<A, E>) => Z
  <A, E, Z>(
    self: Fiber<A, E>,
    options: { readonly onFiber: (fiber: Fiber<A, E>) => Z; readonly onRuntimeFiber: (fiber: RuntimeFiber<A, E>) => Z }
  ): Z
}

Source

Since v2.0.0

getters

await

Awaits the fiber, which suspends the awaiting fiber until the result of the fiber has been determined.

Signature

declare const await: <A, E>(self: Fiber<A, E>) => Effect.Effect<Exit.Exit<A, E>>

Source

Since v2.0.0

children

Retrieves the immediate children of the fiber.

Signature

declare const children: <A, E>(self: Fiber<A, E>) => Effect.Effect<Array<RuntimeFiber<any, any>>>

Source

Since v2.0.0

id

The identity of the fiber.

Signature

declare const id: <A, E>(self: Fiber<A, E>) => FiberId.FiberId

Source

Since v2.0.0

poll

Tentatively observes the fiber, but returns immediately if it is not already done.

Signature

declare const poll: <A, E>(self: Fiber<A, E>) => Effect.Effect<Option.Option<Exit.Exit<A, E>>>

Source

Since v2.0.0

status

Returns the FiberStatus of a RuntimeFiber.

Signature

declare const status: <A, E>(self: RuntimeFiber<A, E>) => Effect.Effect<FiberStatus.FiberStatus>

Source

Since v2.0.0

instances

Order

Signature

declare const Order: order.Order<RuntimeFiber<unknown, unknown>>

Source

Since v2.0.0

interruption

interrupt

Interrupts the fiber from whichever fiber is calling this method. If the fiber has already exited, the returned effect will resume immediately. Otherwise, the effect will resume when the fiber exits.

Signature

declare const interrupt: <A, E>(self: Fiber<A, E>) => Effect.Effect<Exit.Exit<A, E>>

Source

Since v2.0.0

interruptAll

Interrupts all fibers, awaiting their interruption.

Signature

declare const interruptAll: (fibers: Iterable<Fiber<any, any>>) => Effect.Effect<void>

Source

Since v2.0.0

interruptAllAs

Interrupts all fibers as by the specified fiber, awaiting their interruption.

Signature

declare const interruptAllAs: {
  (fiberId: FiberId.FiberId): (fibers: Iterable<Fiber<any, any>>) => Effect.Effect<void>
  (fibers: Iterable<Fiber<any, any>>, fiberId: FiberId.FiberId): Effect.Effect<void>
}

Source

Since v2.0.0

interruptAs

Interrupts the fiber as if interrupted from the specified fiber. If the fiber has already exited, the returned effect will resume immediately. Otherwise, the effect will resume when the fiber exits.

Signature

declare const interruptAs: {
  (fiberId: FiberId.FiberId): <A, E>(self: Fiber<A, E>) => Effect.Effect<Exit.Exit<A, E>>
  <A, E>(self: Fiber<A, E>, fiberId: FiberId.FiberId): Effect.Effect<Exit.Exit<A, E>>
}

Source

Since v2.0.0

interruptAsFork

Interrupts the fiber as if interrupted from the specified fiber. If the fiber has already exited, the returned effect will resume immediately. Otherwise, the effect will resume when the fiber exits.

Signature

declare const interruptAsFork: {
  (fiberId: FiberId.FiberId): <A, E>(self: Fiber<A, E>) => Effect.Effect<void>
  <A, E>(self: Fiber<A, E>, fiberId: FiberId.FiberId): Effect.Effect<void>
}

Source

Since v2.0.0

interruptFork

Interrupts the fiber from whichever fiber is calling this method. The interruption will happen in a separate daemon fiber, and the returned effect will always resume immediately without waiting.

Signature

declare const interruptFork: <A, E>(self: Fiber<A, E>) => Effect.Effect<void>

Source

Since v2.0.0

mapping

map

Maps over the value the Fiber computes.

Signature

declare const map: {
  <A, B>(f: (a: A) => B): <E>(self: Fiber<A, E>) => Fiber<B, E>
  <A, E, B>(self: Fiber<A, E>, f: (a: A) => B): Fiber<B, E>
}

Source

Since v2.0.0

mapEffect

Effectually maps over the value the fiber computes.

Signature

declare const mapEffect: {
  <A, A2, E2>(f: (a: A) => Effect.Effect<A2, E2>): <E>(self: Fiber<A, E>) => Fiber<A2, E2 | E>
  <A, E, A2, E2>(self: Fiber<A, E>, f: (a: A) => Effect.Effect<A2, E2>): Fiber<A2, E | E2>
}

Source

Since v2.0.0

mapFiber

Passes the success of this fiber to the specified callback, and continues with the fiber that it returns.

Signature

declare const mapFiber: {
  <E, E2, A, B>(f: (a: A) => Fiber<B, E2>): (self: Fiber<A, E>) => Effect.Effect<Fiber<B, E | E2>>
  <A, E, E2, B>(self: Fiber<A, E>, f: (a: A) => Fiber<B, E2>): Effect.Effect<Fiber<B, E | E2>>
}

Source

Since v2.0.0

models

Fiber (interface)

A fiber is a lightweight thread of execution that never consumes more than a whole thread (but may consume much less, depending on contention and asynchronicity). Fibers are spawned by forking effects, which run concurrently with the parent effect.

Fibers can be joined, yielding their result to other fibers, or interrupted, which terminates the fiber, safely releasing all resources.

Signature

export interface Fiber<out A, out E = never> extends Effect.Effect<A, E>, Fiber.Variance<A, E> {
  /**
   * The identity of the fiber.
   */
  id(): FiberId.FiberId

  /**
   * Awaits the fiber, which suspends the awaiting fiber until the result of the
   * fiber has been determined.
   */
  readonly await: Effect.Effect<Exit.Exit<A, E>>

  /**
   * Retrieves the immediate children of the fiber.
   */
  readonly children: Effect.Effect<Array<Fiber.Runtime<any, any>>>

  /**
   * Inherits values from all `FiberRef` instances into current fiber. This
   * will resume immediately.
   */
  readonly inheritAll: Effect.Effect<void>

  /**
   * Tentatively observes the fiber, but returns immediately if it is not
   * already done.
   */
  readonly poll: Effect.Effect<Option.Option<Exit.Exit<A, E>>>

  /**
   * In the background, interrupts the fiber as if interrupted from the
   * specified fiber. If the fiber has already exited, the returned effect will
   * resume immediately. Otherwise, the effect will resume when the fiber exits.
   */
  interruptAsFork(fiberId: FiberId.FiberId): Effect.Effect<void>

  readonly [Unify.typeSymbol]?: unknown
  readonly [Unify.unifySymbol]?: FiberUnify<this>
  readonly [Unify.ignoreSymbol]?: FiberUnifyIgnore
}

Source

Since v2.0.0

FiberUnify (interface)

Signature

export interface FiberUnify<A extends { [Unify.typeSymbol]?: any }> extends Effect.EffectUnify<A> {
  Fiber?: () => A[Unify.typeSymbol] extends Fiber<infer A0, infer E0> | infer _ ? Fiber<A0, E0> : never
}

Source

Since v3.8.0

FiberUnifyIgnore (interface)

Signature

export interface FiberUnifyIgnore extends Effect.EffectUnifyIgnore {
  Effect?: true
}

Source

Since v3.8.0

RuntimeFiber (interface)

A runtime fiber that is executing an effect. Runtime fibers have an identity and a trace.

Signature

export interface RuntimeFiber<out A, out E = never> extends Fiber<A, E>, Fiber.RuntimeVariance<A, E> {
  /**
   * Reads the current number of ops that have occurred since the last yield
   */
  get currentOpCount(): number

  /**
   * Reads the current value of a fiber ref
   */
  getFiberRef<X>(fiberRef: FiberRef<X>): X

  /**
   * The identity of the fiber.
   */
  id(): FiberId.Runtime

  /**
   * The status of the fiber.
   */
  readonly status: Effect.Effect<FiberStatus.FiberStatus>

  /**
   * Returns the current `RuntimeFlags` the fiber is running with.
   */
  readonly runtimeFlags: Effect.Effect<RuntimeFlags.RuntimeFlags>

  /**
   * Adds an observer to the list of observers.
   */
  addObserver(observer: (exit: Exit.Exit<A, E>) => void): void

  /**
   * Removes the specified observer from the list of observers that will be
   * notified when the fiber exits.
   */
  removeObserver(observer: (exit: Exit.Exit<A, E>) => void): void

  /**
   * Retrieves all fiber refs of the fiber.
   */
  getFiberRefs(): FiberRefs.FiberRefs

  /**
   * Unsafely observes the fiber, but returns immediately if it is not
   * already done.
   */
  unsafePoll(): Exit.Exit<A, E> | null

  /**
   * In the background, interrupts the fiber as if interrupted from the
   * specified fiber. If the fiber has already exited, the returned effect will
   * resume immediately. Otherwise, the effect will resume when the fiber exits.
   */
  unsafeInterruptAsFork(fiberId: FiberId.FiberId): void

  /**
   * Gets the current context
   */
  get currentContext(): Context<never>

  /**
   * Gets the current context
   */
  get currentDefaultServices(): Context<DefaultServices>

  /**
   * Gets the current scheduler
   */
  get currentScheduler(): Scheduler

  /**
   * Gets the current tracer
   */
  get currentTracer(): Tracer

  /**
   * Gets the current span
   */
  get currentSpan(): AnySpan | undefined

  /**
   * Gets the current supervisor
   */
  get currentSupervisor(): Supervisor<unknown>

  readonly [Unify.typeSymbol]?: unknown
  readonly [Unify.unifySymbol]?: RuntimeFiberUnify<this>
  readonly [Unify.ignoreSymbol]?: RuntimeFiberUnifyIgnore
}

Source

Since v2.0.0

RuntimeFiberUnify (interface)

Signature

export interface RuntimeFiberUnify<A extends { [Unify.typeSymbol]?: any }> extends FiberUnify<A> {
  RuntimeFiber?: () => A[Unify.typeSymbol] extends RuntimeFiber<infer A0, infer E0> | infer _
    ? RuntimeFiber<A0, E0>
    : never
}

Source

Since v3.8.0

RuntimeFiberUnifyIgnore (interface)

Signature

export interface RuntimeFiberUnifyIgnore extends FiberUnifyIgnore {
  Fiber?: true
}

Source

Since v3.8.0

refinements

isFiber

Returns true if the specified value is a Fiber, false otherwise.

Signature

declare const isFiber: (u: unknown) => u is Fiber<unknown, unknown>

Source

Since v2.0.0

isRuntimeFiber

Returns true if the specified Fiber is a RuntimeFiber, false otherwise.

Signature

declare const isRuntimeFiber: <A, E>(self: Fiber<A, E>) => self is RuntimeFiber<A, E>

Source

Since v2.0.0

symbols

FiberTypeId

Signature

declare const FiberTypeId: unique symbol

Source

Since v2.0.0

FiberTypeId (type alias)

Signature

type FiberTypeId = typeof FiberTypeId

Source

Since v2.0.0

RuntimeFiberTypeId

Signature

declare const RuntimeFiberTypeId: unique symbol

Source

Since v2.0.0

RuntimeFiberTypeId (type alias)

Signature

type RuntimeFiberTypeId = typeof RuntimeFiberTypeId

Source

Since v2.0.0

utilities

getCurrentFiber

Gets the current fiber if one is running.

Signature

declare const getCurrentFiber: () => Option.Option<RuntimeFiber<any, any>>

Source

Since v2.0.0

utils

Fiber (namespace)

Source

Since v2.0.0

Variance (interface)

Signature

export interface Variance<out A, out E> {
  readonly [FiberTypeId]: {
    readonly _A: Types.Covariant<A>
    readonly _E: Types.Covariant<E>
  }
}

Source

Since v2.0.0

RuntimeVariance (interface)

Signature

export interface RuntimeVariance<out A, out E> {
  readonly [RuntimeFiberTypeId]: {
    readonly _A: Types.Covariant<A>
    readonly _E: Types.Covariant<E>
  }
}

Source

Since v2.0.0

Dump (interface)

Signature

export interface Dump {
  /**
   * The fiber's unique identifier.
   */
  readonly id: FiberId.Runtime
  /**
   * The status of the fiber.
   */
  readonly status: FiberStatus.FiberStatus
}

Source

Since v2.0.0

Descriptor (interface)

A record containing information about a Fiber.

Signature

export interface Descriptor {
  /**
   * The fiber's unique identifier.
   */
  readonly id: FiberId.FiberId
  /**
   * The status of the fiber.
   */
  readonly status: FiberStatus.FiberStatus
  /**
   * The set of fibers attempting to interrupt the fiber or its ancestors.
   */
  readonly interruptors: HashSet.HashSet<FiberId.FiberId>
}

Source

Since v2.0.0

Runtime (type alias)

Signature

type Runtime<A, E> = RuntimeFiber<A, E>

Source

Since v2.0.0

zipping

zip

Zips this fiber and the specified fiber together, producing a tuple of their output.

Signature

declare const zip: {
  <A2, E2>(that: Fiber<A2, E2>): <A, E>(self: Fiber<A, E>) => Fiber<[A, A2], E2 | E>
  <A, E, A2, E2>(self: Fiber<A, E>, that: Fiber<A2, E2>): Fiber<[A, A2], E | E2>
}

Source

Since v2.0.0

zipLeft

Same as zip but discards the output of that Fiber.

Signature

declare const zipLeft: {
  <A2, E2>(that: Fiber<A2, E2>): <A, E>(self: Fiber<A, E>) => Fiber<A, E2 | E>
  <A, E, A2, E2>(self: Fiber<A, E>, that: Fiber<A2, E2>): Fiber<A, E | E2>
}

Source

Since v2.0.0

zipRight

Same as zip but discards the output of this Fiber.

Signature

declare const zipRight: {
  <A2, E2>(that: Fiber<A2, E2>): <A, E>(self: Fiber<A, E>) => Fiber<A2, E2 | E>
  <A, E, A2, E2>(self: Fiber<A, E>, that: Fiber<A2, E2>): Fiber<A2, E | E2>
}

Source

Since v2.0.0

zipWith

Zips this fiber with the specified fiber, combining their results using the specified combiner function. Both joins and interruptions are performed in sequential order from left to right.

Signature

declare const zipWith: {
  <B, E2, A, C>(that: Fiber<B, E2>, f: (a: A, b: B) => C): <E>(self: Fiber<A, E>) => Fiber<C, E2 | E>
  <A, E, B, E2, C>(self: Fiber<A, E>, that: Fiber<B, E2>, f: (a: A, b: B) => C): Fiber<C, E | E2>
}

Source

Since v2.0.0