| /** | |
| * Provides low-level building blocks for streaming data through Effect. | |
| * | |
| * A `Channel` can read input elements, write output elements, fail with a typed | |
| * error, and finish with a typed result while managing resources safely. | |
| * Streams and sinks are built on channels, so most application code uses those | |
| * higher-level modules instead. This module is useful when implementing stream | |
| * operators or specialized streaming workflows. | |
| * | |
| * @since 2.0.0 | |
| */ | |
| // @effect-diagnostics returnEffectInGen:off | |
| import * as Arr from "./Array.js"; | |
| import * as Cause from "./Cause.js"; | |
| import * as Chunk from "./Chunk.js"; | |
| import * as Context from "./Context.js"; | |
| import * as Effect from "./Effect.js"; | |
| import * as Exit from "./Exit.js"; | |
| import * as Fiber from "./Fiber.js"; | |
| import { constant, constTrue, constVoid, dual, identity as identity_ } from "./Function.js"; | |
| import { ClockRef, endSpan } from "./internal/effect.js"; | |
| import { addSpanStackTrace } from "./internal/tracer.js"; | |
| import * as Iterable from "./Iterable.js"; | |
| import * as Latch from "./Latch.js"; | |
| import * as Layer from "./Layer.js"; | |
| import * as Option from "./Option.js"; | |
| import { pipeArguments } from "./Pipeable.js"; | |
| import { hasProperty, isTagged } from "./Predicate.js"; | |
| import * as PubSub from "./PubSub.js"; | |
| import * as Pull from "./Pull.js"; | |
| import * as Queue from "./Queue.js"; | |
| import { TracerTimingEnabled } from "./References.js"; | |
| import * as Result from "./Result.js"; | |
| import * as Schedule from "./Schedule.js"; | |
| import * as Scope from "./Scope.js"; | |
| import * as Semaphore from "./Semaphore.js"; | |
| import * as String from "./String.js"; | |
| import * as Take from "./Take.js"; | |
| import { ParentSpan } from "./Tracer.js"; | |
| /** | |
| * Runtime identifier stored on `Channel` values and used by `isChannel` to | |
| * recognize them. | |
| * | |
| * @category type IDs | |
| * @since 4.0.0 | |
| */ | |
| export const TypeId = "~effect/Channel"; | |
| /** | |
| * Checks whether a value is a `Channel`. | |
| * | |
| * **Example** (Checking for channels) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const channel = Channel.succeed(42) | |
| * console.log(Channel.isChannel(channel)) // true | |
| * console.log(Channel.isChannel("not a channel")) // false | |
| * ``` | |
| * | |
| * @category guards | |
| * @since 3.5.4 | |
| */ | |
| export const isChannel = u => hasProperty(u, TypeId); | |
| const ChannelProto = { | |
| [TypeId]: { | |
| _Env: identity_, | |
| _InErr: identity_, | |
| _InElem: identity_, | |
| _OutErr: identity_, | |
| _OutElem: identity_ | |
| }, | |
| pipe() { | |
| return pipeArguments(this, arguments); | |
| } | |
| }; | |
| // ----------------------------------------------------------------------------- | |
| // Constructors | |
| // ----------------------------------------------------------------------------- | |
| /** | |
| * Creates a `Channel` from a transformation function that operates on upstream pulls. | |
| * | |
| * **Example** (Creating channels from transforms) | |
| * | |
| * ```ts | |
| * import { Channel, Effect } from "effect" | |
| * | |
| * const channel = Channel.fromTransform((upstream, scope) => | |
| * Effect.succeed(upstream) | |
| * ) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromTransform = transform => { | |
| const self = Object.create(ChannelProto); | |
| self.transform = (upstream, scope) => Effect.catchCause(transform(upstream, scope), cause => Effect.succeed(Effect.failCause(cause))); | |
| return self; | |
| }; | |
| /** | |
| * Transforms a Channel by applying a function to its Pull implementation. | |
| * | |
| * **Example** (Transforming pull behavior) | |
| * | |
| * ```ts | |
| * import { Channel, Effect } from "effect" | |
| * | |
| * // Transform a channel by modifying its pull behavior | |
| * const originalChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * const transformedChannel = Channel.transformPull( | |
| * originalChannel, | |
| * (pull, scope) => | |
| * Effect.succeed( | |
| * Effect.map(pull, (value) => value * 2) | |
| * ) | |
| * ) | |
| * // Outputs: 2, 4, 6 | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const transformPull = (self, f) => fromTransform((upstream, scope) => Effect.flatMap(toTransform(self)(upstream, scope), pull => f(pull, scope))); | |
| /** | |
| * Creates a `Channel` from an `Effect` that produces a `Pull`. | |
| * | |
| * **Example** (Creating channels from pulls) | |
| * | |
| * ```ts | |
| * import { Channel, Effect } from "effect" | |
| * | |
| * const channel = Channel.fromPull( | |
| * Effect.succeed(Effect.succeed(42)) | |
| * ) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromPull = effect => fromTransform((_, __) => effect); | |
| /** | |
| * Creates a `Channel` from a transformation function that operates on upstream | |
| * pulls, but also provides a forked scope that closes when the resulting | |
| * Channel completes. | |
| * | |
| * **When to use** | |
| * | |
| * Use when building channels that require scoped resource lifecycle management, | |
| * providing both the channel scope and a forked scope that automatically closes | |
| * when the channel completes. | |
| * | |
| * @see {@link fromTransform} for a simpler transformation without a forked scope | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromTransformBracket = f => fromTransform(Effect.fnUntraced(function* (upstream, scope) { | |
| const closableScope = Scope.forkUnsafe(scope); | |
| const onCause = cause => Scope.close(closableScope, Pull.doneExitFromCause(cause)); | |
| const pull = yield* Effect.onError(f(upstream, scope, closableScope), onCause); | |
| return Effect.onError(pull, onCause); | |
| })); | |
| /** | |
| * Converts a `Channel` back to its underlying transformation function. | |
| * | |
| * **Example** (Extracting channel transforms) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const channel = Channel.succeed(42) | |
| * const transform = Channel.toTransform(channel) | |
| * // transform can now be used directly | |
| * ``` | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const toTransform = channel => channel.transform; | |
| /** | |
| * The default chunk size used by channels for batching operations. | |
| * | |
| * **Example** (Reading the default chunk size) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * console.log(Channel.DefaultChunkSize) // 4096 | |
| * ``` | |
| * | |
| * @category constants | |
| * @since 4.0.0 | |
| */ | |
| export const DefaultChunkSize = 4096; | |
| const asyncQueue = (scope, f, options) => Queue.make({ | |
| capacity: options?.bufferSize, | |
| strategy: options?.strategy | |
| }).pipe(Effect.tap(queue => Scope.addFinalizer(scope, Queue.shutdown(queue))), Effect.tap(queue => Effect.forkIn(Scope.provide(f(queue), scope), scope))); | |
| /** | |
| * Creates a `Channel` that interacts with a callback function using a queue. | |
| * | |
| * **Example** (Creating channels from callbacks) | |
| * | |
| * ```ts | |
| * import { Channel, Effect, Queue } from "effect" | |
| * | |
| * const channel = Channel.callback<number>((queue) => | |
| * Effect.gen(function*() { | |
| * yield* Queue.offer(queue, 1) | |
| * yield* Queue.offer(queue, 2) | |
| * yield* Queue.offer(queue, 3) | |
| * }) | |
| * ) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const callback = (f, options) => fromTransform((_, scope) => Effect.map(asyncQueue(scope, f, options), Queue.take)); | |
| /** | |
| * Creates a `Channel` that interacts with a callback function using a queue, emitting arrays. | |
| * | |
| * **Example** (Creating array channels from callbacks) | |
| * | |
| * ```ts | |
| * import { Channel, Effect, Queue } from "effect" | |
| * | |
| * const channel = Channel.callbackArray<number>(Effect.fn(function*(queue) { | |
| * yield* Queue.offer(queue, 1) | |
| * yield* Queue.offer(queue, 2) | |
| * })) | |
| * // Emits arrays of numbers instead of individual numbers | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const callbackArray = (f, options) => fromTransform((_, scope) => Effect.map(asyncQueue(scope, f, options), Queue.takeAll)); | |
| /** | |
| * Creates a `Channel` that lazily evaluates to another channel. | |
| * | |
| * **Example** (Suspending channel creation) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const channel = Channel.suspend(() => Channel.succeed(42)) | |
| * // The inner channel is not created until the suspended channel is run | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const suspend = evaluate => fromTransform((upstream, scope) => Effect.suspend(() => toTransform(evaluate())(upstream, scope))); | |
| /** | |
| * Acquires a resource, uses it to build a `Channel`, and guarantees that | |
| * `release` runs with the channel's `Exit` when the channel completes, fails, | |
| * or is interrupted. | |
| * | |
| * **Details** | |
| * | |
| * Acquisition is uninterruptible. If acquisition fails, `use` is not run and | |
| * `release` is not registered. | |
| * | |
| * **Example** (Managing resources with acquire-use-release) | |
| * | |
| * ```ts | |
| * import { Channel, Effect } from "effect" | |
| * | |
| * const channel = Channel.acquireUseRelease( | |
| * Effect.succeed("resource"), | |
| * (resource) => Channel.succeed(resource.toUpperCase()), | |
| * (resource, exit) => Effect.log(`Released: ${resource}`) | |
| * ) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const acquireUseRelease = (acquire, use, release) => fromTransformBracket(Effect.fnUntraced(function* (upstream, scope, forkedScope) { | |
| let option = Option.none(); | |
| yield* Scope.addFinalizerExit(forkedScope, exit => Option.isSome(option) ? release(option.value, exit) : Effect.void); | |
| const value = yield* Effect.uninterruptible(acquire); | |
| option = Option.some(value); | |
| return yield* toTransform(use(value))(upstream, scope); | |
| })); | |
| /** | |
| * Acquires a resource, emits the acquired value as a single channel element, | |
| * and registers `release` in the channel scope. | |
| * | |
| * **Details** | |
| * | |
| * The release action runs when the channel scope closes and receives the scope | |
| * exit. If acquisition fails, no element is emitted and `release` is not | |
| * registered. | |
| * | |
| * **Example** (Managing resources with acquire-release) | |
| * | |
| * ```ts | |
| * import { Channel, Effect } from "effect" | |
| * | |
| * const channel = Channel.acquireRelease( | |
| * Effect.succeed("resource"), | |
| * (resource, exit) => Effect.log(`Released: ${resource}`) | |
| * ) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const acquireRelease = /*#__PURE__*/dual(2, (self, release) => unwrap(Effect.map(Effect.acquireRelease(self, release), succeed))); | |
| /** | |
| * Creates a `Channel` from an iterator. | |
| * | |
| * **Example** (Creating channels from iterators) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const numbers = [1, 2, 3, 4, 5] | |
| * const channel = Channel.fromIterator(() => numbers[Symbol.iterator]()) | |
| * // Emits: 1, 2, 3, 4, 5 | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromIterator = iterator => fromPull(Effect.sync(() => { | |
| const iter = iterator(); | |
| return Effect.suspend(() => { | |
| const state = iter.next(); | |
| return state.done ? Cause.done(state.value) : Effect.succeed(state.value); | |
| }); | |
| })); | |
| /** | |
| * Creates a `Channel` that emits all elements from an array. | |
| * | |
| * **Example** (Creating channels from arrays) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const channel = Channel.fromArray([1, 2, 3, 4, 5]) | |
| * // Emits: 1, 2, 3, 4, 5 | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromArray = array => fromPull(Effect.sync(() => { | |
| let index = 0; | |
| return Effect.suspend(() => index >= array.length ? Cause.done() : Effect.succeed(array[index++])); | |
| })); | |
| /** | |
| * Creates a `Channel` that emits all elements from a chunk. | |
| * | |
| * **Example** (Creating channels from chunks) | |
| * | |
| * ```ts | |
| * import { Channel, Chunk } from "effect" | |
| * | |
| * const chunk = Chunk.make(1, 2, 3) | |
| * const channel = Channel.fromChunk(chunk) | |
| * // Emits: 1, 2, 3 | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromChunk = chunk => fromArray(Chunk.toReadonlyArray(chunk)); | |
| /** | |
| * Creates a `Channel` from an iterator that emits arrays of elements. | |
| * | |
| * **Example** (Batching iterator output) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create a channel from a simple iterator | |
| * const numberIterator = (): Iterator<number, string> => { | |
| * let count = 0 | |
| * return { | |
| * next: () => { | |
| * if (count < 3) { | |
| * return { value: count++, done: false } | |
| * } | |
| * return { value: "finished", done: true } | |
| * } | |
| * } | |
| * } | |
| * | |
| * const channel = Channel.fromIteratorArray(() => numberIterator(), 2) | |
| * // This will emit arrays: [0, 1], [2], then complete with "finished" | |
| * ``` | |
| * | |
| * **Example** (Batching generator output) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create channel from a generator function | |
| * function* fibonacci(): Generator<number, void, unknown> { | |
| * let a = 0, b = 1 | |
| * for (let i = 0; i < 5; i++) { | |
| * yield a | |
| * ;[a, b] = [b, a + b] | |
| * } | |
| * } | |
| * | |
| * const fibChannel = Channel.fromIteratorArray(() => fibonacci(), 3) | |
| * // Emits: [0, 1, 1], [2, 3], then completes | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromIteratorArray = (iterator, chunkSize = DefaultChunkSize) => fromPull(Effect.sync(() => { | |
| const iter = iterator(); | |
| let done = Option.none(); | |
| return Effect.suspend(() => { | |
| if (done._tag === "Some") return Cause.done(done.value); | |
| const buffer = []; | |
| while (buffer.length < chunkSize) { | |
| const state = iter.next(); | |
| if (state.done) { | |
| if (buffer.length === 0) { | |
| return Cause.done(state.value); | |
| } | |
| done = Option.some(state.value); | |
| break; | |
| } | |
| buffer.push(state.value); | |
| } | |
| return Effect.succeed(buffer); | |
| }); | |
| })); | |
| /** | |
| * Creates a `Channel` that emits all elements from an iterable. | |
| * | |
| * **Example** (Creating channels from iterables) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const set = new Set([1, 2, 3]) | |
| * const channel = Channel.fromIterable(set) | |
| * // Emits: 1, 2, 3 | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromIterable = iterable => fromIterator(() => iterable[Symbol.iterator]()); | |
| /** | |
| * Creates a `Channel` that emits arrays of elements from an iterable. | |
| * | |
| * **Example** (Batching iterable output) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const numbers = [1, 2, 3, 4, 5] | |
| * const channel = Channel.fromIterableArray(numbers) | |
| * // Emits arrays like: [1, 2, 3, 4], [5] (based on chunk size) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromIterableArray = (iterable, chunkSize = DefaultChunkSize) => fromIteratorArray(() => iterable[Symbol.iterator](), chunkSize); | |
| /** | |
| * Creates a `Channel` that emits a single value and then ends. | |
| * | |
| * **Example** (Creating channels that succeed) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const channel = Channel.succeed(42) | |
| * // Emits: 42 | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const succeed = value => fromEffect(Effect.succeed(value)); | |
| /** | |
| * Creates a `Channel` that immediately ends with the specified value. | |
| * | |
| * **Example** (Ending with a value) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * const channel = Channel.end("done") | |
| * // Ends immediately with "done", emits nothing | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const end = value => fromPull(Effect.succeed(Cause.done(value))); | |
| /** | |
| * Creates a `Channel` that immediately ends with the lazily evaluated value. | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const endSync = evaluate => fromPull(Effect.sync(() => Cause.done(evaluate()))); | |
| /** | |
| * Creates a `Channel` that emits a single value computed by a lazy evaluation. | |
| * | |
| * **Example** (Computing values lazily) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * let requests = 0 | |
| * | |
| * const channel = Channel.sync(() => { | |
| * requests += 1 | |
| * return `request-${requests}` | |
| * }) | |
| * // Emits "request-1" when the channel runs for the first time | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const sync = evaluate => fromEffect(Effect.sync(evaluate)); | |
| /** | |
| * Represents a `Channel` that emits no elements. | |
| * | |
| * **Example** (Using empty channels) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create an empty channel | |
| * const emptyChannel = Channel.empty | |
| * | |
| * // Use empty channel in composition | |
| * const combined = Channel.concatWith(emptyChannel, () => Channel.succeed(42)) | |
| * // Will immediately provide the second channel's output | |
| * | |
| * // Empty channel can be used as a no-op in conditional logic | |
| * const conditionalChannel = (shouldEmit: boolean) => | |
| * shouldEmit ? Channel.succeed("data") : Channel.empty | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const empty = /*#__PURE__*/fromPull(/*#__PURE__*/Effect.succeed(/*#__PURE__*/Cause.done())); | |
| /** | |
| * Represents a `Channel` that never completes. | |
| * | |
| * **Example** (Using non-terminating channels) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create a channel that never completes | |
| * const neverChannel = Channel.never | |
| * | |
| * // Use in conditional logic | |
| * const withFallback = Channel.concatWith( | |
| * neverChannel, | |
| * () => Channel.succeed("fallback") | |
| * ) | |
| * | |
| * // Never channel is useful for testing or as a placeholder | |
| * const conditionalChannel = (shouldComplete: boolean) => | |
| * shouldComplete ? Channel.succeed("done") : Channel.never | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const never = /*#__PURE__*/fromPull(/*#__PURE__*/Effect.succeed(Effect.never)); | |
| /** | |
| * Constructs a channel that fails immediately with the specified error. | |
| * | |
| * **Example** (Failing with an error) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create a channel that fails with a string error | |
| * const failedChannel = Channel.fail("Something went wrong") | |
| * | |
| * // Create a channel that fails with a custom error | |
| * class CustomError extends Error { | |
| * constructor(message: string) { | |
| * super(message) | |
| * this.name = "CustomError" | |
| * } | |
| * } | |
| * const customErrorChannel = Channel.fail(new CustomError("Custom error")) | |
| * | |
| * // Use in error handling by piping to another channel | |
| * const channelWithFallback = Channel.concatWith( | |
| * failedChannel, | |
| * () => Channel.succeed("fallback value") | |
| * ) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const fail = error => fromPull(Effect.succeed(Effect.fail(error))); | |
| /** | |
| * Constructs a channel that fails immediately with the specified lazily | |
| * evaluated error. | |
| * | |
| * **When to use** | |
| * | |
| * Use when the error value should be computed each time the channel runs instead | |
| * of when the channel is constructed. | |
| * | |
| * **Example** (Failing with a lazy error) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create a channel that fails with a lazily computed error | |
| * const failedChannel = Channel.failSync(() => { | |
| * console.log("Computing error...") | |
| * return new Error("Computed at runtime") | |
| * }) | |
| * | |
| * // The error computation is deferred until the channel runs | |
| * let attempts = 0 | |
| * const conditionalError = Channel.failSync(() => { | |
| * attempts += 1 | |
| * return `Error after attempt ${attempts}` | |
| * }) | |
| * | |
| * // Use with expensive error construction | |
| * const expensiveError = Channel.failSync(() => { | |
| * const requestId = "request-123" | |
| * return new Error(`Failed while processing ${requestId}`) | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const failSync = evaluate => fromPull(Effect.failSync(evaluate)); | |
| /** | |
| * 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) | |
| * | |
| * ```ts | |
| * 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) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const failCause = cause => fromPull(Effect.failCause(cause)); | |
| /** | |
| * Constructs a channel that fails immediately with the specified lazily | |
| * evaluated `Cause`. | |
| * | |
| * **Example** (Failing with lazy causes) | |
| * | |
| * ```ts | |
| * import { Cause, Channel } from "effect" | |
| * | |
| * // Create a channel that fails with a lazily computed cause | |
| * let attempts = 0 | |
| * const failedChannel = Channel.failCauseSync(() => { | |
| * attempts += 1 | |
| * return Cause.fail(`Runtime error after attempt ${attempts}`) | |
| * }) | |
| * | |
| * // Create a channel with die cause computation | |
| * const dieCauseChannel = Channel.failCauseSync(() => { | |
| * const operation = "load-profile" | |
| * return Cause.die(`Unexpected defect during ${operation}`) | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const failCauseSync = evaluate => fromPull(Effect.failCauseSync(evaluate)); | |
| /** | |
| * Constructs a channel that fails immediately with the specified defect. | |
| * | |
| * **Example** (Dying with defects) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create a channel that dies with a string defect | |
| * const diedChannel = Channel.die("Unrecoverable error") | |
| * | |
| * // Create a channel that dies with an Error object | |
| * const errorDefect = Channel.die(new Error("System failure")) | |
| * | |
| * // Die with any value as a defect | |
| * const objectDefect = Channel.die({ | |
| * code: "SYSTEM_FAILURE", | |
| * details: "Critical system component failed" | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const die = defect => failCause(Cause.die(defect)); | |
| /** | |
| * Uses an effect to write a single value to the channel. | |
| * | |
| * **Example** (Creating channels from effects) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect } from "effect" | |
| * | |
| * class DatabaseError extends Data.TaggedError("DatabaseError")<{ | |
| * readonly message: string | |
| * }> {} | |
| * | |
| * // Create a channel from a successful effect | |
| * const successChannel = Channel.fromEffect( | |
| * Effect.succeed("Hello from effect!") | |
| * ) | |
| * | |
| * // Create a channel from an effect that might fail | |
| * const fetchUserChannel = Channel.fromEffect( | |
| * Effect.tryPromise({ | |
| * try: () => fetch("/api/user").then((res) => res.json()), | |
| * catch: (error) => new DatabaseError({ message: String(error) }) | |
| * }) | |
| * ) | |
| * | |
| * // Channel from effect with async computation | |
| * const asyncChannel = Channel.fromEffect( | |
| * Effect.gen(function*() { | |
| * yield* Effect.sleep("100 millis") | |
| * return "Async result" | |
| * }) | |
| * ) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const fromEffect = effect => fromPull(Effect.sync(() => { | |
| let done = false; | |
| return Effect.suspend(() => { | |
| if (done) return Cause.done(); | |
| done = true; | |
| return effect; | |
| }); | |
| })); | |
| /** | |
| * Creates a channel that evaluates an effect and uses its successful value as | |
| * the channel's done value without emitting any output elements. | |
| * | |
| * **Details** | |
| * | |
| * If the effect fails, the channel fails with the effect's error. | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromEffectDone = effect => fromPull(Effect.succeed(Effect.flatMap(effect, Cause.done))); | |
| /** | |
| * Uses an effect and discards its result. | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromEffectDrain = effect => fromPull(Effect.flatMap(effect, () => Cause.done())); | |
| /** | |
| * Creates a channel from an effect that produces a `Take`. | |
| * | |
| * **Details** | |
| * | |
| * A successful `Take` emits a non-empty array of output elements. A failed | |
| * `Take` fails the channel. A done `Take` completes the channel with its done | |
| * value. | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromEffectTake = effect => fromPull(Effect.succeed(Effect.flatMap(effect, Take.toPull))); | |
| /** | |
| * Creates a channel from a queue. | |
| * | |
| * **Example** (Creating channels from queues) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect, Queue } from "effect" | |
| * | |
| * class QueueError extends Data.TaggedError("QueueError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * const program = Effect.gen(function*() { | |
| * // Create a bounded queue | |
| * const queue = yield* Queue.bounded<string, QueueError>(10) | |
| * | |
| * // Add some items to the queue | |
| * yield* Queue.offer(queue, "item1") | |
| * yield* Queue.offer(queue, "item2") | |
| * yield* Queue.offer(queue, "item3") | |
| * | |
| * // Create a channel from the queue | |
| * const channel = Channel.fromQueue(queue) | |
| * | |
| * // The channel will read items from the queue one by one | |
| * return channel | |
| * }) | |
| * | |
| * // Sliding queue example | |
| * const slidingProgram = Effect.gen(function*() { | |
| * const slidingQueue = yield* Queue.sliding<number, QueueError>(5) | |
| * yield* Queue.offerAll(slidingQueue, [1, 2, 3, 4, 5, 6]) | |
| * return Channel.fromQueue(slidingQueue) | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const fromQueue = queue => fromPull(Effect.succeed(Queue.take(queue))); | |
| /** | |
| * Creates a channel from a queue that emits arrays of elements. | |
| * | |
| * **Example** (Creating batched channels from queues) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect, Queue } from "effect" | |
| * | |
| * class ProcessingError extends Data.TaggedError("ProcessingError")<{ | |
| * readonly stage: string | |
| * }> {} | |
| * | |
| * const program = Effect.gen(function*() { | |
| * // Create a queue for batch processing | |
| * const queue = yield* Queue.bounded<number, ProcessingError>(100) | |
| * | |
| * // Fill queue with data | |
| * yield* Queue.offerAll(queue, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]) | |
| * | |
| * // Create a channel that reads arrays from the queue | |
| * const arrayChannel = Channel.fromQueueArray(queue) | |
| * | |
| * // This will emit non-empty arrays of elements instead of individual items | |
| * // Useful for batch processing scenarios | |
| * return arrayChannel | |
| * }) | |
| * | |
| * // High-throughput processing example | |
| * const batchProcessor = Effect.gen(function*() { | |
| * const dataQueue = yield* Queue.dropping<string, ProcessingError>(1000) | |
| * const batchChannel = Channel.fromQueueArray(dataQueue) | |
| * | |
| * // Process data in batches for better performance | |
| * return Channel.map( | |
| * batchChannel, | |
| * (batch) => batch.map((item) => item.toUpperCase()) | |
| * ) | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromQueueArray = queue => fromPull(Effect.succeed(Queue.takeAll(queue))); | |
| /** | |
| * Creates a channel that forwards upstream input elements, input errors, and | |
| * the upstream done value unchanged. | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const identity = () => fromTransform((upstream, _scope) => Effect.succeed(upstream)); | |
| /** | |
| * Creates a channel from a PubSub subscription. | |
| * | |
| * **Example** (Creating channels from subscriptions) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect, PubSub } from "effect" | |
| * | |
| * class SubscriptionError extends Data.TaggedError("SubscriptionError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * const program = Effect.gen(function*() { | |
| * // Create a PubSub | |
| * const pubsub = yield* PubSub.bounded<string>(32) | |
| * | |
| * // Create a subscription | |
| * const subscription = yield* PubSub.subscribe(pubsub) | |
| * | |
| * // Publish some messages | |
| * yield* PubSub.publish(pubsub, "Hello") | |
| * yield* PubSub.publish(pubsub, "World") | |
| * yield* PubSub.publish(pubsub, "from") | |
| * yield* PubSub.publish(pubsub, "PubSub") | |
| * | |
| * // Create a channel from the subscription | |
| * const channel = Channel.fromSubscription(subscription) | |
| * | |
| * // The channel will receive all published messages | |
| * return channel | |
| * }) | |
| * | |
| * // Real-time notifications example | |
| * const notificationChannel = Effect.gen(function*() { | |
| * const eventBus = yield* PubSub.unbounded<{ type: string; payload: any }>() | |
| * const userSubscription = yield* PubSub.subscribe(eventBus) | |
| * | |
| * return Channel.fromSubscription(userSubscription) | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromSubscription = subscription => fromPull(Effect.succeed(Effect.onInterrupt(PubSub.take(subscription), () => Cause.done()))); | |
| /** | |
| * Creates a channel from a PubSub subscription that outputs arrays of values. | |
| * | |
| * **Details** | |
| * | |
| * This constructor creates a channel that reads from a PubSub subscription and outputs | |
| * arrays of values in chunks. It's useful when you want to process multiple values at once | |
| * for better performance. | |
| * | |
| * **Example** (Batching subscription values) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect, PubSub } from "effect" | |
| * | |
| * class StreamError extends Data.TaggedError("StreamError")<{ | |
| * readonly message: string | |
| * }> {} | |
| * | |
| * const program = Effect.gen(function*() { | |
| * const pubsub = yield* PubSub.bounded<number>(16) | |
| * const subscription = yield* PubSub.subscribe(pubsub) | |
| * | |
| * // Create a channel that reads arrays of values | |
| * const channel = Channel.fromSubscriptionArray(subscription) | |
| * | |
| * // Publish some values | |
| * yield* PubSub.publish(pubsub, 1) | |
| * yield* PubSub.publish(pubsub, 2) | |
| * yield* PubSub.publish(pubsub, 3) | |
| * yield* PubSub.publish(pubsub, 4) | |
| * | |
| * // The channel will output arrays like [1, 2, 3] and [4] | |
| * return channel | |
| * }) | |
| * ``` | |
| * | |
| * **Example** (Processing subscription values in batches) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect, PubSub } from "effect" | |
| * | |
| * class BatchProcessingError extends Data.TaggedError("BatchProcessingError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * const batchProcessor = Effect.gen(function*() { | |
| * const pubsub = yield* PubSub.bounded<string>(32) | |
| * const subscription = yield* PubSub.subscribe(pubsub) | |
| * | |
| * // Create a channel that processes items in batches | |
| * const batchChannel = Channel.fromSubscriptionArray(subscription) | |
| * | |
| * // Transform to process each batch | |
| * const processedChannel = Channel.map(batchChannel, (batch) => { | |
| * console.log(`Processing batch of ${batch.length} items:`, batch) | |
| * return batch.map((item) => item.toUpperCase()) | |
| * }) | |
| * | |
| * return processedChannel | |
| * }) | |
| * ``` | |
| * | |
| * **Example** (Aggregating subscription metrics) | |
| * | |
| * ```ts | |
| * import { Channel, Effect, PubSub } from "effect" | |
| * | |
| * const metricsAggregator = Effect.gen(function*() { | |
| * const metricsPubSub = yield* PubSub.bounded< | |
| * { timestamp: number; value: number } | |
| * >(100) | |
| * const subscription = yield* PubSub.subscribe(metricsPubSub) | |
| * | |
| * // Create a channel that collects metrics in chunks | |
| * const metricsChannel = Channel.fromSubscriptionArray(subscription) | |
| * | |
| * // Transform to calculate aggregate statistics | |
| * const aggregatedChannel = Channel.map(metricsChannel, (metrics) => { | |
| * const values = metrics.map((m) => m.value) | |
| * const sum = values.reduce((a, b) => a + b, 0) | |
| * const avg = sum / values.length | |
| * const min = Math.min(...values) | |
| * const max = Math.max(...values) | |
| * | |
| * return { | |
| * count: values.length, | |
| * sum, | |
| * average: avg, | |
| * min, | |
| * max, | |
| * firstTimestamp: Math.min(...metrics.map((m) => m.timestamp)), | |
| * lastTimestamp: Math.max(...metrics.map((m) => m.timestamp)) | |
| * } | |
| * }) | |
| * | |
| * return aggregatedChannel | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromSubscriptionArray = subscription => fromPull(Effect.succeed(Effect.onInterrupt(PubSub.takeAll(subscription), () => Cause.done()))); | |
| /** | |
| * Creates a channel from a PubSub that outputs individual values. | |
| * | |
| * **Details** | |
| * | |
| * This constructor creates a channel that reads from a PubSub by automatically | |
| * subscribing to it. The channel outputs individual values as they are published | |
| * to the PubSub, making it ideal for real-time streaming scenarios. | |
| * | |
| * **Example** (Creating channels from PubSubs) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect, PubSub } from "effect" | |
| * | |
| * class StreamError extends Data.TaggedError("StreamError")<{ | |
| * readonly message: string | |
| * }> {} | |
| * | |
| * const program = Effect.gen(function*() { | |
| * const pubsub = yield* PubSub.bounded<number>(16) | |
| * | |
| * // Create a channel that reads individual values | |
| * const channel = Channel.fromPubSub(pubsub) | |
| * | |
| * // Publish some values | |
| * yield* PubSub.publish(pubsub, 1) | |
| * yield* PubSub.publish(pubsub, 2) | |
| * yield* PubSub.publish(pubsub, 3) | |
| * | |
| * // The channel will output: 1, 2, 3 (individual values) | |
| * return channel | |
| * }) | |
| * ``` | |
| * | |
| * **Example** (Streaming PubSub notifications) | |
| * | |
| * ```ts | |
| * import { Channel, Effect, PubSub } from "effect" | |
| * | |
| * const notificationService = Effect.gen(function*() { | |
| * const notificationPubSub = yield* PubSub.bounded<string>(50) | |
| * | |
| * // Create a channel for real-time notifications | |
| * const notificationChannel = Channel.fromPubSub(notificationPubSub) | |
| * | |
| * // Transform notifications to add timestamps | |
| * const receivedAt = "2024-01-01T00:00:00.000Z" | |
| * const timestampedChannel = Channel.map(notificationChannel, (message) => ({ | |
| * message, | |
| * receivedAt, | |
| * id: `notification:${message}` | |
| * })) | |
| * | |
| * return timestampedChannel | |
| * }) | |
| * ``` | |
| * | |
| * **Example** (Processing PubSub events) | |
| * | |
| * ```ts | |
| * import { Channel, Effect, PubSub } from "effect" | |
| * | |
| * interface DomainEvent { | |
| * readonly type: string | |
| * readonly payload: unknown | |
| * readonly timestamp: number | |
| * } | |
| * | |
| * const eventProcessor = Effect.gen(function*() { | |
| * const eventPubSub = yield* PubSub.bounded<DomainEvent>(100) | |
| * | |
| * // Create a channel for processing domain events | |
| * const eventChannel = Channel.fromPubSub(eventPubSub) | |
| * | |
| * // Filter and transform events | |
| * const processedChannel = Channel.map(eventChannel, (event) => { | |
| * if (event.type === "user.created") { | |
| * return { | |
| * ...event, | |
| * processed: true, | |
| * processedAt: event.timestamp + 1 | |
| * } | |
| * } | |
| * return event | |
| * }) | |
| * | |
| * return processedChannel | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const fromPubSub = pubsub => unwrap(Effect.map(PubSub.subscribe(pubsub), fromSubscription)); | |
| /** | |
| * Creates a channel from a PubSub that outputs arrays of values. | |
| * | |
| * **Details** | |
| * | |
| * This constructor creates a channel that reads from a PubSub by automatically | |
| * subscribing to it and collecting values into arrays. The channel outputs | |
| * arrays of values in chunks, making it ideal for batch processing scenarios. | |
| * | |
| * **Example** (Batching PubSub values) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect, PubSub } from "effect" | |
| * | |
| * class BatchError extends Data.TaggedError("BatchError")<{ | |
| * readonly message: string | |
| * }> {} | |
| * | |
| * const program = Effect.gen(function*() { | |
| * const pubsub = yield* PubSub.bounded<number>(16) | |
| * | |
| * // Create a channel that reads arrays of values | |
| * const channel = Channel.fromPubSubArray(pubsub) | |
| * | |
| * // Publish some values | |
| * yield* PubSub.publish(pubsub, 1) | |
| * yield* PubSub.publish(pubsub, 2) | |
| * yield* PubSub.publish(pubsub, 3) | |
| * yield* PubSub.publish(pubsub, 4) | |
| * | |
| * // The channel will output arrays like [1, 2, 3] and [4] | |
| * return channel | |
| * }) | |
| * ``` | |
| * | |
| * **Example** (Processing PubSub orders in batches) | |
| * | |
| * ```ts | |
| * import { Channel, Effect, PubSub } from "effect" | |
| * | |
| * interface Order { | |
| * readonly id: string | |
| * readonly customerId: string | |
| * readonly items: ReadonlyArray<string> | |
| * readonly total: number | |
| * readonly submittedAt: number | |
| * } | |
| * | |
| * const orderBatchProcessor = Effect.gen(function*() { | |
| * const orderPubSub = yield* PubSub.bounded<Order>(100) | |
| * | |
| * // Create a channel that processes orders in batches | |
| * const orderChannel = Channel.fromPubSubArray(orderPubSub) | |
| * | |
| * // Transform to process each batch of orders | |
| * const processedChannel = Channel.map(orderChannel, (orderBatch) => { | |
| * const totalRevenue = orderBatch.reduce((sum, order) => sum + order.total, 0) | |
| * const customerCount = new Set(orderBatch.map((order) => | |
| * order.customerId | |
| * )).size | |
| * | |
| * return { | |
| * batchSize: orderBatch.length, | |
| * totalRevenue, | |
| * uniqueCustomers: customerCount, | |
| * firstSubmittedAt: Math.min(...orderBatch.map((order) => order.submittedAt)), | |
| * orders: orderBatch | |
| * } | |
| * }) | |
| * | |
| * return processedChannel | |
| * }) | |
| * ``` | |
| * | |
| * **Example** (Processing PubSub logs in batches) | |
| * | |
| * ```ts | |
| * import { Channel, Effect, PubSub } from "effect" | |
| * | |
| * interface LogEntry { | |
| * readonly timestamp: number | |
| * readonly level: "info" | "warn" | "error" | |
| * readonly message: string | |
| * readonly source: string | |
| * } | |
| * | |
| * const logAggregator = Effect.gen(function*() { | |
| * const logPubSub = yield* PubSub.bounded<LogEntry>(500) | |
| * | |
| * // Create a channel that collects logs in batches | |
| * const logChannel = Channel.fromPubSubArray(logPubSub) | |
| * | |
| * // Transform to analyze log batches | |
| * const analysisChannel = Channel.map(logChannel, (logBatch) => { | |
| * const errorCount = logBatch.filter((log) => log.level === "error").length | |
| * const warnCount = logBatch.filter((log) => log.level === "warn").length | |
| * const infoCount = logBatch.filter((log) => log.level === "info").length | |
| * | |
| * const timeRange = { | |
| * start: Math.min(...logBatch.map((log) => log.timestamp)), | |
| * end: Math.max(...logBatch.map((log) => log.timestamp)) | |
| * } | |
| * | |
| * return { | |
| * batchId: `${timeRange.start}-${timeRange.end}`, | |
| * totalEntries: logBatch.length, | |
| * errorCount, | |
| * warnCount, | |
| * infoCount, | |
| * timeRange, | |
| * sources: [...new Set(logBatch.map((log) => log.source))] | |
| * } | |
| * }) | |
| * | |
| * return analysisChannel | |
| * }) | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromPubSubArray = pubsub => unwrap(Effect.map(PubSub.subscribe(pubsub), fromSubscriptionArray)); | |
| /** | |
| * Subscribes to a `PubSub` of `Take` values and exposes them as a channel. | |
| * | |
| * **Details** | |
| * | |
| * Output `Take` values are emitted as non-empty arrays. Failed `Take` values | |
| * fail the channel. Done `Take` values complete the channel. | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromPubSubTake = pubsub => unwrap(Effect.map(PubSub.subscribe(pubsub), sub => fromEffectTake(PubSub.take(sub)))); | |
| /** | |
| * Creates a Channel from a Schedule. | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromSchedule = schedule => fromPull(Effect.map(Schedule.toStepWithSleep(schedule), step => step(void 0))); | |
| /** | |
| * Creates a channel that pulls values from an `AsyncIterable`. | |
| * | |
| * **Details** | |
| * | |
| * Each yielded value is emitted as an output element. The iterator's return | |
| * value becomes the channel's done value. Thrown or rejected iterator errors | |
| * are converted with `onError`. If the channel scope closes early and the | |
| * iterator has a `return` method, that method is called. | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromAsyncIterable = (iterable, onError) => fromTransform(Effect.fnUntraced(function* (_, scope) { | |
| const iter = iterable[Symbol.asyncIterator](); | |
| if (iter.return) { | |
| yield* Scope.addFinalizer(scope, Effect.promise(() => iter.return())); | |
| } | |
| return Effect.flatMap(Effect.tryPromise({ | |
| try: () => iter.next(), | |
| catch: onError | |
| }), result => result.done ? Cause.done(result.value) : Effect.succeed(result.value)); | |
| })); | |
| /** | |
| * Creates a channel from an `AsyncIterable`, emitting each yielded value as a | |
| * single-element non-empty array. | |
| * | |
| * **Details** | |
| * | |
| * The iterator's return value becomes the channel's done value. Thrown or | |
| * rejected iterator errors are converted with `onError`. If the channel scope | |
| * closes early and the iterator has a `return` method, that method is called. | |
| * | |
| * @category constructors | |
| * @since 4.0.0 | |
| */ | |
| export const fromAsyncIterableArray = (iterable, onError) => map(fromAsyncIterable(iterable, onError), Arr.of); | |
| /** | |
| * Maps the output of this channel using the specified function. | |
| * | |
| * **Example** (Mapping channel output) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class TransformError extends Data.TaggedError("TransformError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Basic mapping of channel values | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4, 5]) | |
| * const doubledChannel = Channel.map(numbersChannel, (n) => n * 2) | |
| * // Outputs: 2, 4, 6, 8, 10 | |
| * | |
| * // Transform string data | |
| * const wordsChannel = Channel.fromIterable(["hello", "world", "effect"]) | |
| * const upperCaseChannel = Channel.map(wordsChannel, (word) => word.toUpperCase()) | |
| * // Outputs: "HELLO", "WORLD", "EFFECT" | |
| * | |
| * // Complex object transformation | |
| * type User = { id: number; name: string } | |
| * type UserDisplay = { displayName: string; isActive: boolean } | |
| * | |
| * const usersChannel = Channel.fromIterable([ | |
| * { id: 1, name: "Alice" }, | |
| * { id: 2, name: "Bob" } | |
| * ]) | |
| * const displayChannel = Channel.map(usersChannel, (user): UserDisplay => ({ | |
| * displayName: `User: ${user.name}`, | |
| * isActive: true | |
| * })) | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 2.0.0 | |
| */ | |
| export const map = /*#__PURE__*/dual(2, (self, f) => transformPull(self, pull => Effect.sync(() => { | |
| let i = 0; | |
| return Effect.map(pull, o => f(o, i++)); | |
| }))); | |
| /** | |
| * Maps the done value of this channel using the specified function. | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const mapDone = /*#__PURE__*/dual(2, (self, f) => mapDoneEffect(self, o => Effect.succeed(f(o)))); | |
| /** | |
| * Maps the done value of this channel using the specified effectful function. | |
| * | |
| * **When to use** | |
| * | |
| * Use when the terminal done value transformation needs services or can fail, | |
| * while emitted elements should pass through unchanged. | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const mapDoneEffect = /*#__PURE__*/dual(2, (self, f) => transformPull(self, pull => Effect.succeed(Pull.catchDone(pull, done => Effect.flatMap(f(done), Cause.done))))); | |
| const concurrencyIsSequential = concurrency => concurrency === undefined || concurrency !== "unbounded" && concurrency <= 1; | |
| /** | |
| * Maps each output element with an effectful function, preserving the source | |
| * channel's done value. | |
| * | |
| * **When to use** | |
| * | |
| * Use when transforming each channel output needs an Effect, service | |
| * dependency, failure channel, or configured concurrency. | |
| * | |
| * **Details** | |
| * | |
| * The mapping function receives the output element and its zero-based index. | |
| * By default elements are mapped sequentially. Use `options.concurrency` to | |
| * map multiple elements concurrently, and `options.unordered` to allow | |
| * concurrently mapped outputs to be emitted as soon as they complete. | |
| * | |
| * **Example** (Mapping channel output with effects) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect } from "effect" | |
| * | |
| * class NetworkError extends Data.TaggedError("NetworkError")<{ | |
| * readonly url: string | |
| * }> {} | |
| * | |
| * // Transform values using effectful operations | |
| * const urlsChannel = Channel.fromIterable([ | |
| * "/api/users/1", | |
| * "/api/users/2", | |
| * "/api/users/3" | |
| * ]) | |
| * | |
| * const fetchDataChannel = Channel.mapEffect( | |
| * urlsChannel, | |
| * (url) => | |
| * Effect.tryPromise({ | |
| * try: () => fetch(url).then((res) => res.json()), | |
| * catch: () => new NetworkError({ url }) | |
| * }) | |
| * ) | |
| * | |
| * // Concurrent processing with options | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4, 5]) | |
| * const processedChannel = Channel.mapEffect( | |
| * numbersChannel, | |
| * (n) => | |
| * Effect.gen(function*() { | |
| * yield* Effect.sleep("100 millis") // Simulate async work | |
| * return n * n | |
| * }), | |
| * { concurrency: 3, unordered: true } | |
| * ) | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 2.0.0 | |
| */ | |
| export const mapEffect = /*#__PURE__*/dual(args => isChannel(args[0]), (self, f, options) => concurrencyIsSequential(options?.concurrency) ? mapEffectSequential(self, f) : mapEffectConcurrent(self, f, options)); | |
| const mapEffectSequential = (self, f) => fromTransform((upstream, scope) => { | |
| let i = 0; | |
| return Effect.map(toTransform(self)(upstream, scope), Effect.flatMap(o => f(o, i++))); | |
| }); | |
| const mapEffectConcurrent = (self, f, options) => fromTransformBracket(Effect.fnUntraced(function* (upstream, scope, forkedScope) { | |
| let i = 0; | |
| const pull = yield* toTransform(self)(upstream, scope); | |
| const concurrencyN = options.concurrency === "unbounded" ? Number.MAX_SAFE_INTEGER : options.concurrency; | |
| const queue = yield* Queue.bounded(0); | |
| yield* Scope.addFinalizer(forkedScope, Queue.shutdown(queue)); | |
| const runFork = Effect.runForkWith(yield* Effect.context()); | |
| const trackFiber = Fiber.runIn(forkedScope); | |
| if (options.unordered) { | |
| const semaphore = Semaphore.makeUnsafe(concurrencyN); | |
| const release = constant(semaphore.release(1)); | |
| const handle = Effect.matchCauseEffect({ | |
| onFailure: cause => Effect.flatMap(Queue.failCause(queue, cause), release), | |
| onSuccess: value => Effect.flatMap(Queue.offer(queue, value), release) | |
| }); | |
| yield* semaphore.take(1).pipe(Effect.flatMap(() => pull), Effect.flatMap(value => { | |
| trackFiber(runFork(handle(f(value, i++)))); | |
| return Effect.void; | |
| }), Effect.forever({ | |
| disableYield: true | |
| }), Effect.catchCause(cause => semaphore.withPermits(concurrencyN - 1)(Queue.failCause(queue, cause))), Effect.forkIn(forkedScope)); | |
| } else { | |
| // capacity is n - 2 because | |
| // - 1 for the offer *after* starting a fiber | |
| // - 1 for the current processing fiber | |
| const effects = yield* Queue.bounded(concurrencyN - 2); | |
| yield* Scope.addFinalizer(forkedScope, Queue.shutdown(queue)); | |
| yield* Queue.take(effects).pipe(Effect.flatten, Effect.flatMap(value => Queue.offer(queue, value)), Effect.forever({ | |
| disableYield: true | |
| }), Effect.catchCause(cause => Queue.failCause(queue, cause)), Effect.forkIn(forkedScope)); | |
| let errorCause; | |
| const onExit = exit => { | |
| if (exit._tag === "Success") return; | |
| errorCause = exit.cause; | |
| Queue.failCauseUnsafe(queue, exit.cause); | |
| }; | |
| yield* pull.pipe(Effect.flatMap(value => { | |
| if (errorCause) return Effect.failCause(errorCause); | |
| const fiber = runFork(f(value, i++)); | |
| trackFiber(fiber); | |
| fiber.addObserver(onExit); | |
| return Queue.offer(effects, Fiber.join(fiber)); | |
| }), Effect.forever({ | |
| disableYield: true | |
| }), Effect.catchCause(cause => Queue.offer(effects, Exit.failCause(cause)).pipe(Effect.andThen(Queue.failCause(effects, cause)))), Effect.forkIn(forkedScope)); | |
| } | |
| return Queue.take(queue); | |
| })); | |
| /** | |
| * Returns a new channel which is the same as this one but applies the given | |
| * function to the input channel’s input elements. | |
| * | |
| * @category sequencing | |
| * @since 2.0.0 | |
| */ | |
| export const mapInput = /*#__PURE__*/dual(2, (self, f) => fromTransform((upstream, scope) => toTransform(self)(Effect.flatMap(upstream, el => f(el)), scope))); | |
| /** | |
| * Returns a new channel which is the same as this one but applies the given | |
| * function to the input errors. | |
| * | |
| * @category sequencing | |
| * @since 2.0.0 | |
| */ | |
| export const mapInputError = /*#__PURE__*/dual(2, (self, f) => fromTransform((upstream, scope) => toTransform(self)(Effect.catch(upstream, err => { | |
| if (Cause.isDone(err)) return Effect.fail(err); | |
| return Effect.flatMap(f(err), Effect.fail); | |
| }), scope))); | |
| /** | |
| * Applies a side effect function to each output element of the channel, | |
| * returning a new channel that emits the same elements. | |
| * | |
| * **Details** | |
| * | |
| * The `tap` function allows you to perform side effects (like logging or | |
| * debugging) on each element emitted by a channel without modifying the | |
| * elements themselves. | |
| * | |
| * **Example** (Tapping channel output) | |
| * | |
| * ```ts | |
| * import { Channel, Console, Data } from "effect" | |
| * | |
| * class LogError extends Data.TaggedError("LogError")<{ | |
| * readonly message: string | |
| * }> {} | |
| * | |
| * // Create a channel that outputs numbers | |
| * const numberChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // Tap into each output element to perform side effects | |
| * const tappedChannel = Channel.tap( | |
| * numberChannel, | |
| * (n) => Console.log(`Processing number: ${n}`) | |
| * ) | |
| * | |
| * // The channel still outputs the same elements but logs each one | |
| * // Outputs: 1, 2, 3 (while logging each) | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const tap = /*#__PURE__*/dual(args => isChannel(args[0]), (self, f, options) => mapEffect(self, a => Effect.as(f(a), a), options)); | |
| /** | |
| * Maps each output element to a channel and flattens the child channel | |
| * outputs. | |
| * | |
| * **Details** | |
| * | |
| * The source channel's done value is preserved. Child channel done values are | |
| * used only for child-channel completion. By default child channels are run | |
| * sequentially. Use `options.concurrency` and `options.bufferSize` to run child | |
| * channels concurrently. | |
| * | |
| * **Example** (FlatMapping channel output) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class ProcessError extends Data.TaggedError("ProcessError")<{ | |
| * readonly cause: string | |
| * }> {} | |
| * | |
| * // Create a channel that outputs numbers | |
| * const numberChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // FlatMap each number to create new channels | |
| * const flatMappedChannel = Channel.flatMap( | |
| * numberChannel, | |
| * (n) => | |
| * Channel.fromIterable(Array.from({ length: n }, (_, i) => `item-${n}-${i}`)) | |
| * ) | |
| * | |
| * // Flattens nested channels into a single stream | |
| * // Outputs: "item-1-0", "item-2-0", "item-2-1", "item-3-0", "item-3-1", "item-3-2" | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 2.0.0 | |
| */ | |
| export const flatMap = /*#__PURE__*/dual(args => isChannel(args[0]), (self, f, options) => concurrencyIsSequential(options?.concurrency) ? flatMapSequential(self, f) : flatMapConcurrent(self, f, options)); | |
| const flatMapSequential = (self, f) => fromTransform((upstream, scope) => Effect.map(toTransform(self)(upstream, scope), pull => { | |
| let childPull; | |
| let childScope; | |
| const makePull = Effect.flatMap(pull, value => { | |
| childScope ??= Scope.forkUnsafe(scope); | |
| return Effect.flatMapEager(toTransform(f(value))(upstream, childScope), pull => { | |
| childPull = catchHalt(pull); | |
| return childPull; | |
| }); | |
| }); | |
| const catchHalt = Pull.catchDone(_ => { | |
| childPull = undefined; | |
| // we can reuse the scope if the only finalizer is the "fork" one | |
| if (childScope.state._tag === "Open" && childScope.state.finalizers.size === 1) { | |
| return makePull; | |
| } | |
| const close = Scope.close(childScope, Exit.void); | |
| childScope = undefined; | |
| return Effect.flatMap(close, () => makePull); | |
| }); | |
| return Effect.suspend(() => childPull ?? makePull); | |
| })); | |
| const flatMapConcurrent = (self, f, options) => self.pipe(map(f), mergeAll(options)); | |
| /** | |
| * Concatenates this channel with another channel created from the terminal value | |
| * of this channel. The new channel is created using the provided function. | |
| * | |
| * **Example** (Concatenating with completion values) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class ConcatError extends Data.TaggedError("ConcatError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create a channel that outputs numbers and terminates with sum | |
| * const numberChannel = Channel.fromIterable([1, 2, 3]).pipe( | |
| * Channel.concatWith((sum: void) => Channel.succeed(`Completed processing`)) | |
| * ) | |
| * | |
| * // Concatenates additional channel based on completion value | |
| * // Outputs: 1, 2, 3, then "Completed processing" | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const concatWith = /*#__PURE__*/dual(2, (self, f) => fromTransform((upstream, scope) => Effect.sync(() => { | |
| let currentPull; | |
| const forkedScope = Scope.forkUnsafe(scope); | |
| const makePull = Effect.flatMap(toTransform(self)(upstream, forkedScope), pull => { | |
| currentPull = Pull.catchDone(pull, leftover => { | |
| return Scope.close(forkedScope, Exit.void).pipe(Effect.flatMap(() => toTransform(f(leftover))(upstream, scope)), Effect.flatMap(pull => { | |
| currentPull = pull; | |
| return pull; | |
| })); | |
| }); | |
| return currentPull; | |
| }); | |
| return Effect.suspend(() => currentPull ?? makePull); | |
| }))); | |
| /** | |
| * Concatenates this channel with another channel, so that the second channel | |
| * starts emitting values after the first channel has completed. | |
| * | |
| * **Example** (Concatenating channels) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class ConcatError extends Data.TaggedError("ConcatError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create two channels | |
| * const firstChannel = Channel.fromIterable([1, 2, 3]) | |
| * const secondChannel = Channel.fromIterable(["a", "b", "c"]) | |
| * | |
| * // Concatenate them | |
| * const concatenatedChannel = Channel.concat(firstChannel, secondChannel) | |
| * | |
| * // Outputs: 1, 2, 3, "a", "b", "c" | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const concat = /*#__PURE__*/dual(2, (self, that) => concatWith(self, _ => that)); | |
| /** | |
| * Combines two channels with a stateful pull function. | |
| * | |
| * **When to use** | |
| * | |
| * Use to coordinate pulling from two channels when each output element depends | |
| * on both sides and local state. | |
| * | |
| * **Details** | |
| * | |
| * The combining function receives the current state and pull functions for the | |
| * left and right channels. It returns the next output element together with the | |
| * next state. | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const combine = /*#__PURE__*/dual(4, (self, that, s, f) => fromTransform(Effect.fnUntraced(function* (upstream, scope) { | |
| const leftPull = yield* toTransform(self)(upstream, scope); | |
| const rightPull = yield* toTransform(that)(upstream, scope); | |
| let state = s(); | |
| return Effect.suspend(() => { | |
| const combinedPull = f(state, leftPull, rightPull); | |
| return Effect.map(combinedPull, ([a, s1]) => { | |
| state = s1; | |
| return a; | |
| }); | |
| }); | |
| }))); | |
| /** | |
| * Runs a fallback channel if this channel completes without emitting any | |
| * output elements. | |
| * | |
| * **Details** | |
| * | |
| * If the source emits at least one element, the source is used unchanged. If | |
| * the source completes before emitting an element, the fallback function | |
| * receives the source done value and returns the replacement channel. | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const orElseIfEmpty = /*#__PURE__*/dual(2, (self, f) => fromTransform((upstream, scope) => Effect.sync(() => { | |
| let currentPull; | |
| const forkedScope = Scope.forkUnsafe(scope); | |
| const makePull = Effect.flatMap(toTransform(self)(upstream, forkedScope), pull => { | |
| const next = pull.pipe(Effect.tap(() => { | |
| currentPull = pull; | |
| return Effect.void; | |
| }), Pull.catchDone(leftover => Scope.close(forkedScope, Exit.succeed(leftover)).pipe(Effect.andThen(toTransform(f(leftover))(upstream, scope)), Effect.flatMap(pull => { | |
| currentPull = pull; | |
| return pull; | |
| })))); | |
| currentPull = next; | |
| return next; | |
| }); | |
| return Effect.suspend(() => currentPull ?? makePull); | |
| }))); | |
| /** | |
| * Flattens a channel of channels. | |
| * | |
| * **Example** (Flattening nested channels) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class FlattenError extends Data.TaggedError("FlattenError")<{ | |
| * readonly cause: string | |
| * }> {} | |
| * | |
| * // Create a channel that outputs channels | |
| * const nestedChannels = Channel.fromIterable([ | |
| * Channel.fromIterable([1, 2]), | |
| * Channel.fromIterable([3, 4]), | |
| * Channel.fromIterable([5, 6]) | |
| * ]) | |
| * | |
| * // Flatten the nested channels | |
| * const flattenedChannel = Channel.flatten(nestedChannels) | |
| * | |
| * // Outputs: 1, 2, 3, 4, 5, 6 | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const flatten = channels => flatMap(channels, identity_); | |
| /** | |
| * Flattens a channel that outputs arrays into a channel that outputs individual elements. | |
| * | |
| * **Example** (Flattening arrays of channel output) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class FlattenError extends Data.TaggedError("FlattenError")<{ | |
| * readonly message: string | |
| * }> {} | |
| * | |
| * // Create a channel that outputs arrays | |
| * const arrayChannel = Channel.fromIterable([ | |
| * [1, 2, 3], | |
| * [4, 5], | |
| * [6, 7, 8, 9] | |
| * ]) | |
| * | |
| * // Flatten the arrays into individual elements | |
| * const flattenedChannel = Channel.flattenArray(arrayChannel) | |
| * | |
| * // Outputs: 1, 2, 3, 4, 5, 6, 7, 8, 9 | |
| * ``` | |
| * | |
| * @category transforming | |
| * @since 4.0.0 | |
| */ | |
| export const flattenArray = self => transformPull(self, pull => { | |
| let array; | |
| let index = 0; | |
| const pump = Effect.suspend(function loop() { | |
| if (array === undefined) { | |
| return Effect.flatMap(pull, array_ => { | |
| switch (array_.length) { | |
| case 0: | |
| return loop(); | |
| case 1: | |
| return Effect.succeed(array_[0]); | |
| default: | |
| { | |
| array = array_; | |
| return Effect.succeed(array_[index++]); | |
| } | |
| } | |
| }); | |
| } | |
| const next = array[index++]; | |
| if (index >= array.length) { | |
| array = undefined; | |
| index = 0; | |
| } | |
| return Effect.succeed(next); | |
| }); | |
| return Effect.succeed(pump); | |
| }); | |
| /** | |
| * Flattens a channel that emits `Take` values into a channel that emits the | |
| * `Take` outputs directly. | |
| * | |
| * **Details** | |
| * | |
| * Output `Take` values are emitted as non-empty arrays. Failed `Take` values | |
| * fail the returned channel. Done `Take` values complete the returned channel. | |
| * | |
| * @category transforming | |
| * @since 4.0.0 | |
| */ | |
| export const flattenTake = self => mapEffectSequential(self, Take.toPull); | |
| /** | |
| * Creates a new channel that consumes all output from the source channel | |
| * but emits nothing, preserving only the completion value. | |
| * | |
| * **Example** (Draining channel output) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create a channel that outputs values | |
| * const sourceChannel = Channel.fromIterable([1, 2, 3, 4, 5]) | |
| * | |
| * // Drain all output, keeping only the completion | |
| * const drainedChannel = Channel.drain(sourceChannel) | |
| * | |
| * // The channel completes but emits no values | |
| * // Useful for consuming side effects without collecting output | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const drain = self => transformPull(self, pull => Effect.succeed(Effect.forever(pull, { | |
| disableYield: true | |
| }))); | |
| /** | |
| * Repeats this channel according to the provided schedule. | |
| * | |
| * @category repetition | |
| * @since 4.0.0 | |
| */ | |
| export const repeat = /*#__PURE__*/dual(2, (self, schedule) => Schedule.toStepWithMetadata(typeof schedule === "function" ? schedule(identity_) : schedule).pipe(Effect.map(step => { | |
| let meta = Schedule.CurrentMetadata.defaultValue(); | |
| const loop = concatWith(provideServiceEffect(self, Schedule.CurrentMetadata, Effect.sync(() => meta)), done => step(done).pipe(Effect.map(meta_ => { | |
| meta = meta_; | |
| return loop; | |
| }), Pull.catchDone(() => Effect.succeed(end(done))), unwrap)); | |
| return loop; | |
| }), unwrap)); | |
| /** | |
| * Repeats this channel forever. | |
| * | |
| * @category repetition | |
| * @since 4.0.0 | |
| */ | |
| export const forever = self => concatWith(self, () => forever(self)); | |
| /** | |
| * Runs a schedule step for each output element while preserving the emitted | |
| * elements. | |
| * | |
| * **Details** | |
| * | |
| * The schedule receives each output element as input. Schedule delays are | |
| * applied between emitted elements. If the schedule fails, the returned channel | |
| * fails. If the schedule finishes, the returned channel completes with the | |
| * schedule output. | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const schedule = /*#__PURE__*/dual(2, (self, schedule) => transformPull(self, (pull, _scope) => Effect.map(Schedule.toStepWithSleep(schedule), step => { | |
| const pullWithStep = Effect.tap(pull, step); | |
| return pullWithStep; | |
| }))); | |
| /** | |
| * Filters the output elements of a channel using a predicate function. | |
| * Elements that don't match the predicate are discarded. | |
| * | |
| * **Example** (Filtering channel output) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create a channel with mixed numbers | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4, 5, 6, 7, 8]) | |
| * | |
| * // Filter to keep only even numbers | |
| * const evenChannel = Channel.filter(numbersChannel, (n) => n % 2 === 0) | |
| * // Outputs: 2, 4, 6, 8 | |
| * | |
| * // Filter with type refinement | |
| * const mixedChannel = Channel.fromIterable([1, "hello", 2, "world", 3]) | |
| * const numbersOnlyChannel = Channel.filter( | |
| * mixedChannel, | |
| * (value): value is number => typeof value === "number" | |
| * ) | |
| * // Outputs: 1, 2, 3 (all typed as numbers) | |
| * ``` | |
| * | |
| * @category filtering | |
| * @since 4.0.0 | |
| */ | |
| export const filter = /*#__PURE__*/dual(2, (self, predicate) => fromTransform((upstream, scope) => Effect.map(toTransform(self)(upstream, scope), pull => Effect.flatMap(pull, function loop(elem) { | |
| return predicate(elem) ? Effect.succeed(elem) : Effect.flatMap(pull, loop); | |
| })))); | |
| /** | |
| * Filters and maps output elements using a `Filter`. | |
| * | |
| * **When to use** | |
| * | |
| * Use to keep only channel output elements accepted by a `Filter` and emit | |
| * each filter success value. | |
| * | |
| * **Details** | |
| * | |
| * Successful filter results are emitted as mapped values. Failed filter | |
| * results are discarded. The source channel's errors and done value are | |
| * preserved. | |
| * | |
| * @see {@link filter} for keeping original output elements with a predicate | |
| * @see {@link filterMapEffect} for using an effectful `Filter` | |
| * @see {@link filterMapArray} for filtering arrays of output elements | |
| * | |
| * @category filtering | |
| * @since 4.0.0 | |
| */ | |
| export const filterMap = /*#__PURE__*/dual(2, (self, filter) => fromTransform((upstream, scope) => Effect.map(toTransform(self)(upstream, scope), pull => Effect.flatMap(pull, function loop(elem) { | |
| const result = filter(elem); | |
| return Result.isFailure(result) ? Effect.flatMap(pull, loop) : Effect.succeed(result.success); | |
| })))); | |
| /** | |
| * Filters output elements with an effectful predicate. | |
| * | |
| * **When to use** | |
| * | |
| * Use when the keep/discard decision depends on an Effect or service and | |
| * predicate failures should fail the returned channel. | |
| * | |
| * **Details** | |
| * | |
| * Elements for which the predicate succeeds with `true` are emitted. Elements | |
| * for which the predicate succeeds with `false` are discarded. Predicate | |
| * failures fail the returned channel. | |
| * | |
| * @category filtering | |
| * @since 4.0.0 | |
| */ | |
| export const filterEffect = /*#__PURE__*/dual(2, (self, predicate) => fromTransform((upstream, scope) => Effect.map(toTransform(self)(upstream, scope), pull => Effect.flatMap(pull, function loop(elem) { | |
| return Effect.flatMap(predicate(elem), passes => passes ? Effect.succeed(elem) : Effect.flatMap(pull, loop)); | |
| })))); | |
| /** | |
| * Filters and maps output elements using an effectful `Filter`. | |
| * | |
| * **When to use** | |
| * | |
| * Use to apply effectful logic that can discard channel output elements and | |
| * emit transformed values for the elements that pass. | |
| * | |
| * **Details** | |
| * | |
| * Successful filter results are emitted as mapped values. Failed filter | |
| * results are discarded. Failures from the effectful filter fail the returned | |
| * channel. | |
| * | |
| * @see {@link filterMap} for using a synchronous `Filter` | |
| * @see {@link filterEffect} for effectfully keeping original output elements | |
| * @see {@link mapEffect} for effectfully transforming every output element | |
| * @see {@link filterMapArrayEffect} for effectful filtering of array outputs | |
| * | |
| * @category filtering | |
| * @since 4.0.0 | |
| */ | |
| export const filterMapEffect = /*#__PURE__*/dual(2, (self, filter) => fromTransform((upstream, scope) => Effect.map(toTransform(self)(upstream, scope), pull => Effect.flatMap(pull, function loop(elem) { | |
| return Effect.flatMap(filter(elem), result => Result.isFailure(result) ? Effect.flatMap(pull, loop) : Effect.succeed(result.success)); | |
| })))); | |
| /** | |
| * Filters arrays of elements emitted by a channel, applying the filter | |
| * to each element within the arrays and only emitting non-empty filtered arrays. | |
| * | |
| * **Example** (Filtering array output) | |
| * | |
| * ```ts | |
| * import { Array, Channel } from "effect" | |
| * | |
| * const nonEmptyArrayPredicate = Array.isReadonlyArrayNonEmpty | |
| * | |
| * // Create a channel that outputs arrays of mixed data | |
| * const arrayChannel = Channel.fromIterable([ | |
| * Array.make(1, 2, 3, 4, 5), | |
| * Array.make(6, 7, 8, 9, 10), | |
| * Array.make(11, 12, 13, 14, 15) | |
| * ]).pipe(Channel.filter(nonEmptyArrayPredicate)) | |
| * | |
| * // Filter arrays to keep only even numbers | |
| * const evenArraysChannel = Channel.filterArray(arrayChannel, (n) => n % 2 === 0) | |
| * // Outputs: [2, 4], [6, 8, 10], [12, 14] | |
| * // Note: Only non-empty filtered arrays are emitted | |
| * | |
| * // Arrays that would become empty after filtering are discarded entirely | |
| * const oddChannel = Channel.fromIterable([ | |
| * Array.make(1, 3, 5), | |
| * Array.make(2, 4), | |
| * Array.make(7, 9) | |
| * ]).pipe(Channel.filter(nonEmptyArrayPredicate)) | |
| * const filteredOddChannel = Channel.filterArray(oddChannel, (n) => n % 2 === 0) | |
| * // Outputs: [2, 4] (the arrays [1,3,5] and [7,9] are discarded) | |
| * ``` | |
| * | |
| * @category filtering | |
| * @since 4.0.0 | |
| */ | |
| export const filterArray = /*#__PURE__*/dual(2, (self, predicate) => transformPull(self, pull => Effect.succeed(Effect.flatMap(pull, function loop(arr) { | |
| const passes = []; | |
| for (let i = 0; i < arr.length; i++) { | |
| if (predicate(arr[i])) { | |
| passes.push(arr[i]); | |
| } | |
| } | |
| return Arr.isReadonlyArrayNonEmpty(passes) ? Effect.succeed(passes) : Effect.flatMap(pull, loop); | |
| })))); | |
| /** | |
| * Filters and maps each element inside emitted non-empty arrays using a | |
| * `Filter`. | |
| * | |
| * **Details** | |
| * | |
| * Successful filter results are kept as mapped values. Failed filter results | |
| * are removed from the array. Arrays that become empty are discarded. | |
| * | |
| * @category filtering | |
| * @since 4.0.0 | |
| */ | |
| export const filterMapArray = /*#__PURE__*/dual(2, (self, filter) => transformPull(self, pull => Effect.succeed(Effect.flatMap(pull, function loop(arr) { | |
| const passes = []; | |
| for (let i = 0; i < arr.length; i++) { | |
| const result = filter(arr[i]); | |
| if (Result.isSuccess(result)) { | |
| passes.push(result.success); | |
| } | |
| } | |
| return Arr.isReadonlyArrayNonEmpty(passes) ? Effect.succeed(passes) : Effect.flatMap(pull, loop); | |
| })))); | |
| /** | |
| * Filters each element inside emitted non-empty arrays with an effectful | |
| * predicate. | |
| * | |
| * **When to use** | |
| * | |
| * Use when filtering array-valued channel outputs requires Effects or services, | |
| * and arrays that become empty should be skipped. | |
| * | |
| * **Details** | |
| * | |
| * The predicate receives the element and its index within the array. Elements | |
| * for which the predicate succeeds with `true` are kept. Arrays that become | |
| * empty are discarded. Predicate failures fail the returned channel. | |
| * | |
| * @category filtering | |
| * @since 4.0.0 | |
| */ | |
| export const filterArrayEffect = /*#__PURE__*/dual(2, (self, predicate) => transformPull(self, pull => { | |
| const f = Effect.flatMap(pull, arr => Effect.filter(arr, predicate)); | |
| return Effect.succeed(Effect.flatMap(f, function loop(arr) { | |
| return Arr.isReadonlyArrayNonEmpty(arr) ? Effect.succeed(arr) : Effect.flatMap(f, loop); | |
| })); | |
| })); | |
| /** | |
| * Filters and maps each element inside emitted non-empty arrays using an | |
| * effectful `Filter`. | |
| * | |
| * **When to use** | |
| * | |
| * Use when array-valued channel outputs need an effectful filter-map that can | |
| * fail and can discard arrays that become empty. | |
| * | |
| * **Details** | |
| * | |
| * Successful filter results are kept as mapped values. Failed filter results | |
| * are removed from the array. Arrays that become empty are discarded. Failures | |
| * from the effectful filter fail the returned channel. | |
| * | |
| * @category filtering | |
| * @since 4.0.0 | |
| */ | |
| export const filterMapArrayEffect = /*#__PURE__*/dual(2, (self, filter) => transformPull(self, pull => Effect.succeed(Effect.flatMap(pull, function loop(arr) { | |
| return Effect.flatMap(Effect.filterMapEffect(arr, filter), passes => Arr.isReadonlyArrayNonEmpty(passes) ? Effect.succeed(passes) : Effect.flatMap(pull, loop)); | |
| })))); | |
| /** | |
| * Maps over a channel statefully with an accumulator, where each element can produce multiple output values. | |
| * | |
| * **Example** (Mapping with accumulated state) | |
| * | |
| * ```ts | |
| * import { Channel, Effect } from "effect" | |
| * | |
| * // Create a channel with numbers | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4]) | |
| * | |
| * // Use mapAccum to create running sums and emit both current and sum | |
| * const runningSum = Channel.mapAccum( | |
| * numbersChannel, | |
| * () => 0, // initial accumulator state | |
| * (sum, current) => { | |
| * const newSum = sum + current | |
| * // Return [newState, outputValues] | |
| * return [newSum, [current, newSum]] as const | |
| * } | |
| * ) | |
| * // Outputs: 1, 1, 2, 3, 3, 6, 4, 10 | |
| * | |
| * // Using with Effect for async processing | |
| * const asyncMapAccum = Channel.mapAccum( | |
| * numbersChannel, | |
| * () => "", | |
| * (acc, value) => | |
| * Effect.gen(function*() { | |
| * const newAcc = acc + value.toString() | |
| * return [newAcc, [`${value}-processed`, newAcc]] as const | |
| * }) | |
| * ) | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const mapAccum = /*#__PURE__*/dual(args => isChannel(args[0]), (self, initial, f, options) => fromTransform((upstream, scope) => Effect.map(toTransform(self)(upstream, scope), pull => { | |
| let state = initial(); | |
| let current; | |
| let index = 0; | |
| let cause; | |
| const pullNext = Effect.matchCauseEffect(pull, { | |
| onFailure(cause_) { | |
| cause = cause_; | |
| const b = options?.onHalt && options.onHalt(state); | |
| return b && b.length > 0 ? Effect.succeed([state, b]) : Effect.failCause(cause_); | |
| }, | |
| onSuccess(a) { | |
| const b = f(state, a); | |
| return Arr.isArray(b) ? Effect.succeed(b) : b; | |
| } | |
| }); | |
| const pump = Effect.suspend(function loop() { | |
| if (current === undefined) { | |
| if (cause) return Effect.failCause(cause); | |
| return Effect.flatMap(pullNext, ([newState, values]) => { | |
| state = newState; | |
| if (values.length === 0) { | |
| return loop(); | |
| } else if (values.length === 1) { | |
| return Effect.succeed(values[0]); | |
| } | |
| current = values; | |
| return loop(); | |
| }); | |
| } | |
| const next = current[index++]; | |
| if (index >= current.length) { | |
| current = undefined; | |
| index = 0; | |
| } | |
| return Effect.succeed(next); | |
| }); | |
| return pump; | |
| }))); | |
| /** | |
| * Transforms a channel statefully by scanning over its output with an accumulator function. | |
| * Emits the intermediate results of the scan operation. | |
| * | |
| * **Example** (Scanning channel output) | |
| * | |
| * ```ts | |
| * import { Channel } from "effect" | |
| * | |
| * // Create a channel with numbers | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4, 5]) | |
| * | |
| * // Scan to create running sum | |
| * const runningSumChannel = Channel.scan(numbersChannel, 0, (sum, n) => sum + n) | |
| * // Outputs: 0, 1, 3, 6, 10, 15 | |
| * // Note: emits the initial value and each intermediate result | |
| * | |
| * // Scan with string concatenation | |
| * const wordsChannel = Channel.fromIterable(["hello", "world", "from", "effect"]) | |
| * const sentenceChannel = Channel.scan( | |
| * wordsChannel, | |
| * "", | |
| * (sentence, word) => sentence === "" ? word : `${sentence} ${word}` | |
| * ) | |
| * // Outputs: "", "hello", "hello world", "hello world from", "hello world from effect" | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const scan = /*#__PURE__*/dual(3, (self, initial, f) => scanEffect(self, initial, (s, a) => Effect.succeed(f(s, a)))); | |
| /** | |
| * Transforms a channel statefully by scanning over its output with an effectful accumulator function. | |
| * Emits the intermediate results of the scan operation. | |
| * | |
| * **When to use** | |
| * | |
| * Use when maintaining accumulated state over channel output requires Effects | |
| * or can fail, while still emitting each intermediate state. | |
| * | |
| * **Example** (Scanning channel output with effects) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect } from "effect" | |
| * | |
| * class ScanError extends Data.TaggedError("ScanError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create a channel with numbers | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4]) | |
| * | |
| * // Effectful scan with async operations | |
| * const asyncScanChannel = Channel.scanEffect( | |
| * numbersChannel, | |
| * "", | |
| * (acc, value) => | |
| * Effect.gen(function*() { | |
| * // Simulate async work | |
| * yield* Effect.sleep("10 millis") | |
| * return acc + value.toString() | |
| * }) | |
| * ) | |
| * // Outputs: "", "1", "12", "123", "1234" | |
| * | |
| * // Scan with error handling | |
| * const errorHandlingScan = Channel.scanEffect( | |
| * numbersChannel, | |
| * 0, | |
| * (sum, n) => { | |
| * if (n < 0) { | |
| * return Effect.fail(new ScanError({ reason: "negative number" })) | |
| * } | |
| * return Effect.succeed(sum + n) | |
| * } | |
| * ) | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const scanEffect = /*#__PURE__*/dual(3, (self, initial, f) => fromTransform((upstream, scope) => Effect.map(toTransform(self)(upstream, scope), pull => { | |
| let state = initial; | |
| let isFirst = true; | |
| return Effect.suspend(() => { | |
| if (isFirst) { | |
| isFirst = false; | |
| return Effect.succeed(state); | |
| } | |
| return Effect.map(Effect.flatMap(pull, a => f(state, a)), newState => { | |
| state = newState; | |
| return state; | |
| }); | |
| }); | |
| }))); | |
| /** | |
| * Catches any cause of failure from the channel and allows recovery by | |
| * creating a new channel based on the caught cause. | |
| * | |
| * **Example** (Recovering from failure causes) | |
| * | |
| * ```ts | |
| * import { Cause, Channel, Data } from "effect" | |
| * | |
| * class ProcessError extends Data.TaggedError("ProcessError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * class RecoveryError extends Data.TaggedError("RecoveryError")<{ | |
| * readonly message: string | |
| * }> {} | |
| * | |
| * // Create a failing channel | |
| * const failingChannel = Channel.fail( | |
| * new ProcessError({ reason: "network error" }) | |
| * ) | |
| * | |
| * // Catch the cause and provide recovery | |
| * const recoveredChannel = Channel.catchCause(failingChannel, (cause) => { | |
| * if (Cause.hasFails(cause)) { | |
| * return Channel.succeed("Recovered from failure") | |
| * } | |
| * return Channel.succeed("Recovered from interruption") | |
| * }) | |
| * | |
| * // The channel recovers gracefully from errors | |
| * ``` | |
| * | |
| * @category error handling | |
| * @since 2.0.0 | |
| */ | |
| export const catchCause = /*#__PURE__*/dual(2, (self, f) => fromTransform((upstream, scope) => { | |
| let forkedScope = Scope.forkUnsafe(scope); | |
| return Effect.map(toTransform(self)(upstream, forkedScope), pull => { | |
| let currentPull = pull.pipe(Effect.catchCause(cause => { | |
| if (Pull.isDoneCause(cause)) { | |
| return Effect.failCause(cause); | |
| } | |
| const toClose = forkedScope; | |
| forkedScope = Scope.forkUnsafe(scope); | |
| return Scope.close(toClose, Exit.failCause(cause)).pipe(Effect.andThen(toTransform(f(cause))(upstream, forkedScope)), Effect.flatMap(childPull => { | |
| currentPull = childPull; | |
| return childPull; | |
| })); | |
| })); | |
| return Effect.suspend(() => currentPull); | |
| }); | |
| })); | |
| /** | |
| * Runs an effect with the full failure `Cause` when the channel fails, then | |
| * fails the returned channel with the original cause. | |
| * | |
| * **When to use** | |
| * | |
| * Use when observing the full channel failure `Cause` is needed without | |
| * changing successful output or replacing the original cause. | |
| * | |
| * **Details** | |
| * | |
| * Use this for observing failures, such as logging or metrics. If the observer | |
| * effect fails, that failure can fail the returned channel. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const tapCause = /*#__PURE__*/dual(2, (self, f) => catchCause(self, cause => fromEffectDrain(Effect.flatMap(f(cause), _ => Effect.failCause(cause))))); | |
| /** | |
| * Catches causes of failure that match a specific filter, allowing | |
| * conditional error recovery based on the type of failure. | |
| * | |
| * **When to use** | |
| * | |
| * Use to recover a channel only when its full `Cause` satisfies a boolean | |
| * predicate. | |
| * | |
| * **Details** | |
| * | |
| * When the predicate matches, the recovery function receives the original | |
| * cause. When it does not match, the returned channel fails with the original | |
| * cause. | |
| * | |
| * @see {@link catchCauseFilter} for selecting causes with a `Filter` | |
| * @see {@link catchCause} for recovering from every cause | |
| * @see {@link catchIf} for recovering from typed channel errors | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const catchCauseIf = /*#__PURE__*/dual(3, (self, predicate, f) => catchCause(self, cause => { | |
| return predicate(cause) ? f(cause) : failCause(cause); | |
| })); | |
| /** | |
| * 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. | |
| * | |
| * @see {@link catchCauseIf} for selecting causes with a predicate | |
| * @see {@link catchFilter} for selecting typed errors with a `Filter` | |
| * @see {@link catchCause} for recovering from every cause | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const catchCauseFilter = /*#__PURE__*/dual(3, (self, filter, f) => catchCause(self, cause => { | |
| const result = filter(cause); | |
| return Result.isFailure(result) ? failCause(result.failure) : f(result.success, cause); | |
| })); | |
| const catch_ = /*#__PURE__*/dual(2, (self, f) => catchCauseFilter(self, Cause.findError, e => f(e))); | |
| export { | |
| /** | |
| * Recovers from typed channel errors by running a fallback channel. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| catch_ as catch }; | |
| /** | |
| * Runs an effect when the channel fails with a typed error, then preserves the | |
| * original channel failure. | |
| * | |
| * **Details** | |
| * | |
| * The effect is not run for normal channel completion. If the observer effect | |
| * fails, that failure can fail the returned channel. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const tapError = /*#__PURE__*/dual(2, (self, f) => transformPull(self, pull => Effect.succeed(Effect.tapError(pull, err => Cause.isDone(err) ? Effect.void : Effect.asVoid(f(err)))))); | |
| /** | |
| * Recovers from typed channel errors that match a predicate or refinement. | |
| * | |
| * **When to use** | |
| * | |
| * Use to recover from typed channel errors when a predicate or refinement | |
| * selects the failures that should switch to a recovery channel. | |
| * | |
| * **Details** | |
| * | |
| * Matching errors are handled by the recovery function. Non-matching errors | |
| * are handled by `orElse` when provided. Without `orElse`, non-matching errors | |
| * are re-failed. | |
| * | |
| * @see {@link catch_ catch} for recovering from every typed channel error | |
| * @see {@link catchFilter} for selecting typed errors with a `Filter` | |
| * @see {@link catchTag} for selecting tagged typed errors | |
| * @see {@link catchCauseFilter} for selecting full causes with a `Filter` | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const catchIf = /*#__PURE__*/dual(args => isChannel(args[0]), (self, predicate, f, orElse) => catch_(self, err => { | |
| return predicate(err) ? f(err) : orElse ? orElse(err) : fail(err); | |
| })); | |
| /** | |
| * Recovers from typed channel errors selected by a `Filter`. | |
| * | |
| * **When to use** | |
| * | |
| * Use to recover from channel errors with a reusable `Filter` when matching | |
| * can also narrow or transform the error before choosing the recovery channel. | |
| * | |
| * **Details** | |
| * | |
| * Successful filter results are handled by the recovery function. Failed | |
| * filter results are handled by `orElse` when provided. Without `orElse`, | |
| * failed filter results are re-failed. | |
| * | |
| * @see {@link catchIf} for selecting typed errors with a predicate | |
| * @see {@link catchTag} for selecting tagged typed errors | |
| * @see {@link catchCauseFilter} for selecting full causes with a `Filter` | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const catchFilter = /*#__PURE__*/dual(args => isChannel(args[0]), (self, filter, f, orElse) => catch_(self, err => { | |
| const result = filter(err); | |
| return Result.isFailure(result) ? orElse ? orElse(result.failure) : fail(result.failure) : f(result.success); | |
| })); | |
| /** | |
| * Recovers from tagged channel errors whose `_tag` matches one or more tags. | |
| * | |
| * **Details** | |
| * | |
| * Matching tagged errors are handled by the recovery function. Non-matching | |
| * errors are handled by `orElse` when provided. Without `orElse`, | |
| * non-matching errors are re-failed. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const catchTag = /*#__PURE__*/dual(args => isChannel(args[0]), (self, k, f, orElse) => { | |
| const pred = Array.isArray(k) ? e => hasProperty(e, "_tag") && k.includes(e._tag) : isTagged(k); | |
| return catchIf(self, pred, f, orElse); | |
| }); | |
| /** | |
| * Catches a specific reason within a tagged error. | |
| * | |
| * **Example** (Recovering from nested reasons) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class RateLimitError extends Data.TaggedError("RateLimitError")<{ | |
| * retryAfter: number | |
| * }> {} | |
| * | |
| * class QuotaExceededError extends Data.TaggedError("QuotaExceededError")<{ | |
| * limit: number | |
| * }> {} | |
| * | |
| * class AiError extends Data.TaggedError("AiError")<{ | |
| * reason: RateLimitError | QuotaExceededError | |
| * }> {} | |
| * | |
| * const channel = Channel.fail( | |
| * new AiError({ reason: new RateLimitError({ retryAfter: 60 }) }) | |
| * ) | |
| * | |
| * const recovered = channel.pipe( | |
| * Channel.catchReason("AiError", "RateLimitError", (reason) => | |
| * Channel.succeed(`retry: ${reason.retryAfter}`) | |
| * ) | |
| * ) | |
| * ``` | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const catchReason = /*#__PURE__*/dual(args => isChannel(args[0]), (self, errorTag, reasonTag, f, orElse) => catch_(self, error => { | |
| if (isTagged(error, errorTag) && hasProperty(error, "reason")) { | |
| const reason = error.reason; | |
| if (isTagged(reason, reasonTag)) { | |
| return f(reason, error); | |
| } | |
| return orElse ? orElse(reason, error) : fail(error); | |
| } | |
| return fail(error); | |
| })); | |
| /** | |
| * Catches multiple reasons within a tagged error using an object of handlers. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const catchReasons = /*#__PURE__*/dual(args => isChannel(args[0]), (self, errorTag, cases, orElse) => { | |
| let keys; | |
| return catch_(self, error => { | |
| if (isTagged(error, errorTag) && hasProperty(error, "reason") && hasProperty(error.reason, "_tag") && String.isString(error.reason._tag)) { | |
| const reason = error.reason; | |
| keys ??= new Set(Object.keys(cases)); | |
| if (keys.has(reason._tag)) { | |
| return cases[reason._tag](reason, error); | |
| } | |
| return orElse ? orElse(reason, error) : fail(error); | |
| } | |
| return fail(error); | |
| }); | |
| }); | |
| /** | |
| * Promotes nested reason errors into the channel error, replacing the parent error. | |
| * | |
| * **Example** (Promoting nested reasons) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class RateLimitError extends Data.TaggedError("RateLimitError")<{ | |
| * retryAfter: number | |
| * }> {} | |
| * | |
| * class QuotaExceededError extends Data.TaggedError("QuotaExceededError")<{ | |
| * limit: number | |
| * }> {} | |
| * | |
| * class AiError extends Data.TaggedError("AiError")<{ | |
| * reason: RateLimitError | QuotaExceededError | |
| * }> {} | |
| * | |
| * const channel = Channel.fail( | |
| * new AiError({ reason: new RateLimitError({ retryAfter: 60 }) }) | |
| * ) | |
| * | |
| * const unwrapped = channel.pipe(Channel.unwrapReason("AiError")) | |
| * ``` | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const unwrapReason = /*#__PURE__*/dual(2, (self, errorTag) => catchFilter(self, error => isTagged(error, errorTag) && hasProperty(error, "reason") ? Result.succeed(error.reason) : Result.fail(error), fail)); | |
| /** | |
| * Returns a new channel, which is the same as this one, except the failure | |
| * value of the returned channel is created by applying the specified function | |
| * to the failure value of this channel. | |
| * | |
| * @category error handling | |
| * @since 2.0.0 | |
| */ | |
| export const mapError = /*#__PURE__*/dual(2, (self, f) => catch_(self, err => fail(f(err)))); | |
| /** | |
| * Converts all errors in the channel to defects (unrecoverable failures). | |
| * This is useful when you want to treat errors as programming errors. | |
| * | |
| * **Example** (Converting failures to defects) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class ValidationError extends Data.TaggedError("ValidationError")<{ | |
| * readonly field: string | |
| * }> {} | |
| * | |
| * // Create a channel that might fail | |
| * const failingChannel = Channel.fail(new ValidationError({ field: "email" })) | |
| * | |
| * // Convert failures to defects | |
| * const fatalChannel = Channel.orDie(failingChannel) | |
| * | |
| * // Any failure will now become a defect (uncaught exception) | |
| * ``` | |
| * | |
| * @category error handling | |
| * @since 2.0.0 | |
| */ | |
| export const orDie = self => catch_(self, die); | |
| /** | |
| * Ignores all errors in the channel, converting them to an empty channel. | |
| * | |
| * **Details** | |
| * | |
| * Use the `log` option to emit the full {@link Cause} when the channel fails. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const ignore = /*#__PURE__*/dual(args => isChannel(args[0]), (self, options) => { | |
| if (!options?.log) { | |
| return catch_(self, () => empty); | |
| } | |
| const logEffect = Effect.logWithLevel(options.log === true ? undefined : options.log); | |
| return catch_(tapCause(self, cause => Cause.hasFails(cause) ? logEffect(cause) : Effect.void), () => empty); | |
| }); | |
| const ignoreCause_ = self => catchCause(self, () => empty); | |
| /** | |
| * Ignores all errors in the channel including defects, converting them to an empty channel. | |
| * | |
| * **When to use** | |
| * | |
| * Use when a channel should become best-effort and all failure causes, including | |
| * defects and interruptions, can be converted to empty output. | |
| * | |
| * **Details** | |
| * | |
| * Use the `log` option to emit the full {@link Cause} when the channel fails. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const ignoreCause = /*#__PURE__*/dual(args => isChannel(args[0]), (self, options) => { | |
| if (!options?.log) return ignoreCause_(self); | |
| const logEffect = Effect.logWithLevel(options.log === true ? undefined : options.log); | |
| return ignoreCause_(tapCause(self, cause => logEffect(cause))); | |
| }); | |
| /** | |
| * Returns a new channel that retries this channel according to the specified | |
| * schedule whenever it fails. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const retry = /*#__PURE__*/dual(2, (self, schedule) => suspend(() => { | |
| let step = undefined; | |
| let meta = Schedule.CurrentMetadata.defaultValue(); | |
| const selfWithMeta = provideServiceEffect(self, Schedule.CurrentMetadata, Effect.sync(() => meta)); | |
| const withReset = onFirst(selfWithMeta, () => { | |
| step = undefined; | |
| return Effect.void; | |
| }); | |
| const resolvedSchedule = typeof schedule === "function" ? schedule(identity_) : schedule; | |
| const loop = catch_(withReset, Effect.fnUntraced(function* (error) { | |
| if (!step) { | |
| step = yield* Schedule.toStepWithMetadata(resolvedSchedule); | |
| } | |
| meta = yield* step(error); | |
| return loop; | |
| }, (effect, error) => Pull.catchDone(effect, () => Effect.succeed(fail(error))), unwrap)); | |
| return loop; | |
| })); | |
| /** | |
| * Maps each output element to a channel and emits values from the most recent | |
| * active child channels. | |
| * | |
| * **Details** | |
| * | |
| * With the default concurrency of `1`, starting a new child channel interrupts | |
| * the previous child channel. Use `options.concurrency` to allow more active | |
| * child channels. The source channel's done value is preserved. | |
| * | |
| * **Example** (Switching mapped channels) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class SwitchError extends Data.TaggedError("SwitchError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create a channel that outputs numbers | |
| * const numberChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // Switch to new channels based on each value | |
| * const switchedChannel = Channel.switchMap( | |
| * numberChannel, | |
| * (n) => Channel.fromIterable([`value-${n}`]) | |
| * ) | |
| * | |
| * // Outputs: "value-1", "value-2", "value-3" | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 4.0.0 | |
| */ | |
| export const switchMap = /*#__PURE__*/dual(args => isChannel(args[0]), (self, f, options) => self.pipe(map(f), mergeAll({ | |
| ...options, | |
| concurrency: options?.concurrency ?? 1, | |
| switch: true | |
| }))); | |
| /** | |
| * Merges multiple channels with specified concurrency and buffering options. | |
| * | |
| * **When to use** | |
| * | |
| * Use when channel outputs are themselves channels and multiple inner channels | |
| * should run with configured concurrency and buffering. | |
| * | |
| * **Example** (Merging nested channels) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class MergeAllError extends Data.TaggedError("MergeAllError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create channels that output other channels | |
| * const nestedChannels = Channel.fromIterable([ | |
| * Channel.fromIterable([1, 2]), | |
| * Channel.fromIterable([3, 4]), | |
| * Channel.fromIterable([5, 6]) | |
| * ]) | |
| * | |
| * // Merge all channels with bounded concurrency | |
| * const mergedChannel = Channel.mergeAll({ | |
| * concurrency: 2, | |
| * bufferSize: 16 | |
| * })(nestedChannels) | |
| * | |
| * // Outputs: 1, 2, 3, 4, 5, 6 (order may vary due to concurrency) | |
| * ``` | |
| * | |
| * @category combining | |
| * @since 2.0.0 | |
| */ | |
| export const mergeAll = /*#__PURE__*/dual(2, (channels, { | |
| bufferSize = 16, | |
| concurrency, | |
| switch: switch_ = false | |
| }) => fromTransformBracket(Effect.fnUntraced(function* (upstream, scope, forkedScope) { | |
| const concurrencyN = concurrency === "unbounded" ? Number.MAX_SAFE_INTEGER : Math.max(1, concurrency); | |
| const semaphore = switch_ ? undefined : Semaphore.makeUnsafe(concurrencyN); | |
| const doneLatch = yield* Latch.make(true); | |
| const fibers = new Set(); | |
| const queue = yield* Queue.bounded(bufferSize); | |
| yield* Scope.addFinalizer(forkedScope, Queue.shutdown(queue)); | |
| const pull = yield* toTransform(channels)(upstream, scope); | |
| yield* Effect.gen(function* () { | |
| while (true) { | |
| if (semaphore) yield* semaphore.take(1); | |
| const channel = yield* pull; | |
| const childScope = Scope.forkUnsafe(forkedScope); | |
| const childPull = yield* toTransform(channel)(upstream, childScope); | |
| while (fibers.size >= concurrencyN) { | |
| const fiber = Iterable.headUnsafe(fibers); | |
| fibers.delete(fiber); | |
| if (fibers.size === 0) yield* doneLatch.open; | |
| yield* Fiber.interrupt(fiber); | |
| } | |
| const fiber = yield* childPull.pipe(Effect.tap(() => Effect.yieldNow), Effect.flatMap(value => Queue.offer(queue, value)), Effect.forever({ | |
| disableYield: true | |
| }), Effect.onError(Effect.fnUntraced(function* (cause) { | |
| const halt = Pull.filterDone(cause); | |
| yield* Effect.exit(Scope.close(childScope, !Result.isFailure(halt) ? Exit.succeed(halt.success.value) : Exit.failCause(halt.failure))); | |
| if (!fibers.has(fiber)) return; | |
| fibers.delete(fiber); | |
| if (semaphore) yield* semaphore.release(1); | |
| if (fibers.size === 0) yield* doneLatch.open; | |
| if (Result.isSuccess(halt)) return; | |
| return yield* Queue.failCause(queue, cause); | |
| })), Effect.forkChild); | |
| doneLatch.closeUnsafe(); | |
| fibers.add(fiber); | |
| } | |
| }).pipe(Effect.catchCause(cause => doneLatch.whenOpen(Queue.failCause(queue, cause))), Effect.forkIn(forkedScope)); | |
| return Queue.take(queue); | |
| }))); | |
| /** | |
| * Returns a new channel, which is the merge of this channel and the specified | |
| * channel. | |
| * | |
| * **Example** (Merging channels) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class MergeError extends Data.TaggedError("MergeError")<{ | |
| * readonly source: string | |
| * }> {} | |
| * | |
| * // Create two channels | |
| * const leftChannel = Channel.fromIterable([1, 2, 3]) | |
| * const rightChannel = Channel.fromIterable(["a", "b", "c"]) | |
| * | |
| * // Merge them with "either" halt strategy | |
| * const mergedChannel = Channel.merge(leftChannel, rightChannel, { | |
| * haltStrategy: "either" | |
| * }) | |
| * | |
| * // Outputs elements from both channels concurrently | |
| * // Order may vary: 1, "a", 2, "b", 3, "c" | |
| * ``` | |
| * | |
| * @category combining | |
| * @since 4.0.0 | |
| */ | |
| export const merge = /*#__PURE__*/dual(args => isChannel(args[0]) && isChannel(args[1]), (left, right, options) => fromTransformBracket(Effect.fnUntraced(function* (upstream, _scope, forkedScope) { | |
| const strategy = options?.haltStrategy ?? "both"; | |
| const queue = yield* Queue.bounded(0); | |
| yield* Scope.addFinalizer(forkedScope, Queue.shutdown(queue)); | |
| let done = 0; | |
| function onExit(side, cause) { | |
| done++; | |
| if (!Pull.isDoneCause(cause)) { | |
| return Queue.failCause(queue, cause); | |
| } | |
| switch (strategy) { | |
| case "both": | |
| { | |
| return done === 2 ? Queue.failCause(queue, cause) : Effect.void; | |
| } | |
| case "left": | |
| case "right": | |
| { | |
| return side === strategy ? Queue.failCause(queue, cause) : Effect.void; | |
| } | |
| case "either": | |
| { | |
| return Queue.failCause(queue, cause); | |
| } | |
| } | |
| } | |
| const runSide = (side, channel, scope) => toTransform(channel)(upstream, scope).pipe(Effect.flatMap(pull => pull.pipe(Effect.flatMap(value => Queue.offer(queue, value)), Effect.forever)), Effect.onError(cause => Effect.andThen(Scope.close(scope, Pull.doneExitFromCause(cause)), onExit(side, cause))), Effect.forkIn(forkedScope)); | |
| yield* runSide("left", left, Scope.forkUnsafe(forkedScope)); | |
| yield* runSide("right", right, Scope.forkUnsafe(forkedScope)); | |
| return Queue.take(queue); | |
| }))); | |
| /** | |
| * Runs an effect concurrently with a channel while emitting only the channel's | |
| * output elements. | |
| * | |
| * **When to use** | |
| * | |
| * Use when a side effect should run for the lifetime of a channel and only the | |
| * channel's output elements should be emitted. | |
| * | |
| * **Details** | |
| * | |
| * The effect's successful value is ignored. If the effect fails while the | |
| * channel is running, the returned channel fails with that error. | |
| * | |
| * @category combining | |
| * @since 4.0.0 | |
| */ | |
| export const mergeEffect = /*#__PURE__*/dual(2, (self, effect) => merge(self, fromEffectDrain(effect), { | |
| haltStrategy: "left" | |
| })); | |
| /** | |
| * Splits upstream string chunks into lines, recognizing `\n`, `\r\n`, and | |
| * standalone `\r` as line terminators. The behavior matches | |
| * `String.linesIterator` regardless of how the input is chunked. | |
| * | |
| * **Details** | |
| * | |
| * A line terminator at the very end of the stream does **not** produce a | |
| * trailing empty line (consistent with `String.linesIterator`). Conversely, | |
| * if the stream ends without a terminator the final partial line is still | |
| * emitted. | |
| * | |
| * **Example** (Splitting string chunks into lines) | |
| * | |
| * ```ts | |
| * import { Effect, Stream } from "effect" | |
| * | |
| * Effect.runPromise(Effect.gen(function*() { | |
| * const result = yield* Stream.runCollect( | |
| * Stream.splitLines(Stream.make("hel", "lo\r\nwor", "ld\n")) | |
| * ) | |
| * console.log(result) | |
| * // [ 'hello', 'world' ] | |
| * })) | |
| * ``` | |
| * | |
| * @category String manipulation | |
| * @since 2.0.0 | |
| */ | |
| export const splitLines = () => fromTransform((upstream, _scope) => Effect.sync(() => { | |
| // Accumulates text that has not yet been terminated by a line break. | |
| // Content is carried across chunks until a terminator is found. | |
| let stringBuilder = ""; | |
| // Set when a chunk ends with \r so the next chunk can check whether | |
| // the following character is \n (completing a \r\n pair) or not | |
| // (standalone \r, which is itself a line terminator). | |
| let midCRLF = false; | |
| // Remembers the upstream Done value after the first time the upstream | |
| // signals completion, so subsequent pulls return Done immediately | |
| // without pulling upstream again. | |
| let done = Option.none(); | |
| function splitLinesArray(chunk) { | |
| const chunkBuilder = []; | |
| function pushLine(segment) { | |
| if (stringBuilder.length === 0) { | |
| chunkBuilder.push(segment); | |
| } else { | |
| chunkBuilder.push(stringBuilder + segment); | |
| stringBuilder = ""; | |
| } | |
| } | |
| for (let i = 0; i < chunk.length; i++) { | |
| const str = chunk[i]; | |
| if (str.length !== 0) { | |
| let from = 0; | |
| let indexOfCR = str.indexOf("\r"); | |
| let indexOfLF = str.indexOf("\n"); | |
| if (midCRLF) { | |
| if (indexOfLF === 0) { | |
| pushLine(""); | |
| from = 1; | |
| indexOfLF = str.indexOf("\n", from); | |
| } else { | |
| pushLine(""); | |
| } | |
| midCRLF = false; | |
| } | |
| while (indexOfCR !== -1 || indexOfLF !== -1) { | |
| if (indexOfCR === -1 || indexOfLF !== -1 && indexOfLF < indexOfCR) { | |
| pushLine(str.substring(from, indexOfLF)); | |
| from = indexOfLF + 1; | |
| indexOfLF = str.indexOf("\n", from); | |
| } else { | |
| if (str.length === indexOfCR + 1) { | |
| midCRLF = true; | |
| indexOfCR = -1; | |
| } else { | |
| pushLine(str.substring(from, indexOfCR)); | |
| from = indexOfCR + (indexOfLF === indexOfCR + 1 ? 2 : 1); | |
| indexOfCR = str.indexOf("\r", from); | |
| indexOfLF = str.indexOf("\n", from); | |
| } | |
| } | |
| } | |
| stringBuilder = stringBuilder + str.substring(from, str.length - (midCRLF ? 1 : 0)); | |
| } | |
| } | |
| return Arr.isReadonlyArrayNonEmpty(chunkBuilder) ? chunkBuilder : null; | |
| } | |
| const pullOrFlush = Effect.suspend(() => { | |
| if (done._tag === "Some") { | |
| return Cause.done(done.value); | |
| } | |
| return Pull.matchEffect(upstream, { | |
| onSuccess: loop, | |
| onFailure: Effect.failCause, | |
| onDone: leftover => { | |
| done = Option.some(leftover); | |
| if (stringBuilder.length > 0 || midCRLF) { | |
| const last = stringBuilder; | |
| stringBuilder = ""; | |
| midCRLF = false; | |
| return Effect.succeed([last]); | |
| } | |
| return Cause.done(leftover); | |
| } | |
| }); | |
| }); | |
| function loop(chunk) { | |
| const lines = splitLinesArray(chunk); | |
| return lines !== null ? Effect.succeed(lines) : pullOrFlush; | |
| } | |
| return pullOrFlush; | |
| })); | |
| /** | |
| * Decodes incoming `Uint8Array` chunks into strings using `TextDecoder`. | |
| * | |
| * **Details** | |
| * | |
| * Input chunks are decoded with streaming enabled so multi-byte characters may | |
| * span `Uint8Array` boundaries. The optional `encoding` and `options` are | |
| * passed to `TextDecoder`. | |
| * | |
| * @category String manipulation | |
| * @since 4.0.0 | |
| */ | |
| export const decodeText = (encoding, options) => fromTransform((upstream, _scope) => Effect.sync(() => { | |
| const decoder = new TextDecoder(encoding, options); | |
| const streamOptions = { | |
| stream: true | |
| }; | |
| return Effect.map(upstream, Arr.map(line => decoder.decode(line, streamOptions))); | |
| })); | |
| /** | |
| * Encodes incoming string chunks into `Uint8Array` values using `TextEncoder`. | |
| * | |
| * **Details** | |
| * | |
| * Each string inside an emitted array is encoded independently. | |
| * | |
| * @category String manipulation | |
| * @since 4.0.0 | |
| */ | |
| export const encodeText = () => fromTransform((upstream, _scope) => Effect.sync(() => { | |
| const encoder = new TextEncoder(); | |
| return Effect.map(upstream, Arr.map(line => encoder.encode(line))); | |
| })); | |
| /** | |
| * Returns a new channel that pipes the output of this channel into the | |
| * specified channel. The returned channel has the input type of this channel, | |
| * and the output type of the specified channel, terminating with the value of | |
| * the specified channel. | |
| * | |
| * **Example** (Piping one channel into another) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class PipeError extends Data.TaggedError("PipeError")<{ | |
| * readonly stage: string | |
| * }> {} | |
| * | |
| * // Create source and transform channels | |
| * const sourceChannel = Channel.fromIterable([1, 2, 3]) | |
| * const transformChannel = Channel.map(sourceChannel, (n: number) => n * 2) | |
| * | |
| * // Pipe the source into the transform | |
| * const pipedChannel = Channel.pipeTo(sourceChannel, transformChannel) | |
| * | |
| * // Outputs: 2, 4, 6 | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 2.0.0 | |
| */ | |
| export const pipeTo = /*#__PURE__*/dual(2, (self, that) => fromTransform((upstream, scope) => Effect.flatMap(toTransform(self)(upstream, scope), upstream => toTransform(that)(upstream, scope)))); | |
| /** | |
| * Returns a new channel that pipes the output of this channel into the | |
| * specified channel and preserves this channel's failures without providing | |
| * them to the other channel for observation. | |
| * | |
| * **Example** (Piping while preserving failures) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class SourceError extends Data.TaggedError("SourceError")<{ | |
| * readonly code: number | |
| * }> {} | |
| * | |
| * // Create a failing source channel | |
| * const failingSource = Channel.fail(new SourceError({ code: 404 })) | |
| * const safeTransform = Channel.succeed("transformed") | |
| * | |
| * // Pipe while preserving source failures | |
| * const safePipedChannel = Channel.pipeToOrFail(failingSource, safeTransform) | |
| * | |
| * // Source errors are preserved and not sent to transform channel | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 2.0.0 | |
| */ | |
| export const pipeToOrFail = /*#__PURE__*/dual(2, (self, that) => fromTransform((upstream, scope) => Effect.flatMap(toTransform(self)(upstream, scope), upstream => { | |
| const upstreamPull = Effect.catchCause(upstream, cause => Pull.isDoneCause(cause) ? Effect.failCause(cause) : Effect.die(Cause.Done(cause))); | |
| return Effect.map(toTransform(that)(upstreamPull, scope), pull => Effect.catchDefect(pull, defect => Cause.isDone(defect) ? Effect.failCause(defect.value) : Effect.die(defect))); | |
| }))); | |
| /** | |
| * Constructs a `Channel` from a scoped effect that will result in a | |
| * `Channel` if successful. | |
| * | |
| * **Example** (Unwrapping channel effects) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect } from "effect" | |
| * | |
| * class UnwrapError extends Data.TaggedError("UnwrapError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create an effect that produces a channel | |
| * const channelEffect = Effect.succeed( | |
| * Channel.fromIterable([1, 2, 3]) | |
| * ) | |
| * | |
| * // Unwrap the effect to get the channel | |
| * const unwrappedChannel = Channel.unwrap(channelEffect) | |
| * | |
| * // The resulting channel outputs: 1, 2, 3 | |
| * ``` | |
| * | |
| * @category constructors | |
| * @since 2.0.0 | |
| */ | |
| export const unwrap = channel => fromTransform((upstream, scope) => { | |
| let pull; | |
| return Effect.succeed(Effect.suspend(() => { | |
| if (pull) return pull; | |
| return channel.pipe(Scope.provide(scope), Effect.flatMap(channel => toTransform(channel)(upstream, scope)), Effect.flatMap(pull_ => pull = pull_)); | |
| })); | |
| }); | |
| /** | |
| * Runs a channel with a scope provided for the duration of the channel | |
| * execution, removing the channel's `Scope` requirement. | |
| * | |
| * @category resource management | |
| * @since 2.0.0 | |
| */ | |
| export const scoped = self => fromTransformBracket((upstream, scope, forkedScope) => Effect.map(Scope.provide(toTransform(self)(upstream, scope), forkedScope), Scope.provide(forkedScope))); | |
| /** | |
| * Runs an input handler against the upstream pull while the wrapped channel | |
| * runs without receiving upstream input directly. | |
| * | |
| * **Details** | |
| * | |
| * The input handler is forked in the channel scope. The wrapped channel is run | |
| * with an already-completed input. | |
| * | |
| * **Example** (Embedding custom input handling) | |
| * | |
| * ```ts | |
| * import { Channel, Effect } from "effect" | |
| * | |
| * // Create a base channel | |
| * const baseChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // Drain the embedded input while the base channel runs | |
| * const embeddedChannel = Channel.embedInput( | |
| * baseChannel, | |
| * (upstream) => | |
| * upstream.pipe( | |
| * Effect.tap((message) => | |
| * Effect.sync(() => console.log(message)) | |
| * ), | |
| * Effect.forever, | |
| * Effect.ignore | |
| * ) | |
| * ) | |
| * ``` | |
| * | |
| * @category sequencing | |
| * @since 2.0.0 | |
| */ | |
| export const embedInput = /*#__PURE__*/dual(2, (self, input) => fromTransformBracket((upstream, scope, forkedScope) => Effect.andThen(Effect.forkIn(input(upstream), forkedScope), toTransform(self)(Cause.done(), scope)))); | |
| /** | |
| * Buffers individual output elements in a queue with the configured `capacity` | |
| * so a faster producer can progress independently of a slower consumer. | |
| * | |
| * **When to use** | |
| * | |
| * Use when output elements can be decoupled from downstream demand and the | |
| * configured backpressure or loss strategy is acceptable. | |
| * | |
| * **Details** | |
| * | |
| * Finite queues use the `strategy` option. The default `"suspend"` strategy | |
| * applies backpressure, while `"dropping"` and `"sliding"` can discard output | |
| * elements when the queue is full. `"unbounded"` capacity does not use a finite | |
| * capacity strategy. | |
| * | |
| * **Gotchas** | |
| * | |
| * Dropping and sliding strategies can lose output elements under backpressure. | |
| * | |
| * @see {@link bufferArray} for buffering elements from array outputs | |
| * | |
| * @category Buffering | |
| * @since 2.0.0 | |
| */ | |
| export const buffer = /*#__PURE__*/dual(2, (self, options) => fromTransform(Effect.fnUntraced(function* (upstream, scope) { | |
| const pull = yield* toTransform(self)(upstream, scope); | |
| const queue = yield* Queue.make({ | |
| capacity: options.capacity === "unbounded" ? undefined : options.capacity, | |
| strategy: options.capacity === "unbounded" ? undefined : options.strategy | |
| }); | |
| yield* Scope.addFinalizer(scope, Queue.shutdown(queue)); | |
| yield* pull.pipe(Effect.flatMap(value => Queue.offer(queue, value)), Effect.forever({ | |
| disableYield: true | |
| }), Effect.onError(cause => Queue.failCause(queue, cause)), Effect.forkIn(scope)); | |
| return Queue.take(queue); | |
| }))); | |
| /** | |
| * Buffers array output elements in a queue with the configured `capacity` so a | |
| * faster producer can progress independently of a slower consumer. | |
| * | |
| * **When to use** | |
| * | |
| * Use when emitted arrays are batches of elements and it is acceptable for | |
| * buffering to flatten and rebuild those batches. | |
| * | |
| * **Details** | |
| * | |
| * Finite queues use the `strategy` option. The default `"suspend"` strategy | |
| * applies backpressure, while `"dropping"` and `"sliding"` can discard output | |
| * elements when the queue is full. `"unbounded"` capacity does not use a finite | |
| * capacity strategy. | |
| * | |
| * **Gotchas** | |
| * | |
| * Input arrays are offered to the queue element-by-element and outputs are | |
| * rebuilt from the currently available queued elements, so upstream array | |
| * boundaries are not preserved. | |
| * | |
| * @see {@link buffer} for buffering output elements without flattening arrays | |
| * | |
| * @category Buffering | |
| * @since 4.0.0 | |
| */ | |
| export const bufferArray = /*#__PURE__*/dual(2, (self, options) => fromTransform(Effect.fnUntraced(function* (upstream, scope) { | |
| const pull = yield* toTransform(self)(upstream, scope); | |
| const queue = yield* Queue.make({ | |
| capacity: options.capacity === "unbounded" ? undefined : options.capacity, | |
| strategy: options.capacity === "unbounded" ? undefined : options.strategy | |
| }); | |
| yield* Scope.addFinalizer(scope, Queue.shutdown(queue)); | |
| yield* pull.pipe(Effect.flatMap(value => Queue.offerAll(queue, value)), Effect.forever({ | |
| disableYield: true | |
| }), Effect.onError(cause => Queue.failCause(queue, cause)), Effect.forkIn(scope)); | |
| return Queue.takeAll(queue); | |
| }))); | |
| /** | |
| * Interrupts a channel when another effect completes. | |
| * | |
| * **When to use** | |
| * | |
| * Use to race channel execution against an external effect whose success can | |
| * become the channel's done value. | |
| * | |
| * **Details** | |
| * | |
| * If the effect completes first, its success value becomes the returned | |
| * channel's done value. If the channel completes first, the original channel's | |
| * done value is preserved. | |
| * | |
| * @category interruption | |
| * @since 2.0.0 | |
| */ | |
| export const interruptWhen = /*#__PURE__*/dual(2, (self, effect) => merge(self, fromPull(Effect.succeed(Effect.flatMap(effect, Cause.done))), { | |
| haltStrategy: "either" | |
| })); | |
| /** | |
| * Stops a channel when the specified effect completes or fails. | |
| * | |
| * **Details** | |
| * | |
| * If the effect completes before the channel is done, its success value becomes | |
| * the returned channel's done value. If the effect fails, the returned channel | |
| * fails with that error. If the channel completes first, the channel's done | |
| * value is preserved. | |
| * | |
| * @category interruption | |
| * @since 4.0.0 | |
| */ | |
| export const haltWhen = /*#__PURE__*/dual(2, (self, effect) => fromTransformBracket(Effect.fnUntraced(function* (upstream, scope, forkedScope) { | |
| const pull = yield* toTransform(self)(upstream, scope); | |
| let haltCause = undefined; | |
| yield* effect.pipe(Effect.catchCause(cause => { | |
| haltCause = cause; | |
| return Effect.void; | |
| }), Effect.forkIn(forkedScope)); | |
| return Effect.suspend(() => haltCause ? Effect.failCause(haltCause) : pull); | |
| }))); | |
| /** | |
| * Attaches a finalizer that runs only when the channel exits with failure. | |
| * | |
| * **Details** | |
| * | |
| * The finalizer receives the failure `Cause`. The original channel failure is | |
| * preserved. The finalizer itself must not fail. | |
| * | |
| * @category error handling | |
| * @since 4.0.0 | |
| */ | |
| export const onError = /*#__PURE__*/dual(2, (self, finalizer) => onExit(self, exit => Exit.isFailure(exit) ? finalizer(exit.cause) : Effect.void)); | |
| /** | |
| * Returns a channel with an exit-aware finalizer that is guaranteed to run once | |
| * the channel begins execution, whether it succeeds or fails. | |
| * | |
| * **Example** (Running exit finalizers) | |
| * | |
| * ```ts | |
| * import { Channel, Console, Data, Exit } from "effect" | |
| * | |
| * class ExitError extends Data.TaggedError("ExitError")<{ | |
| * readonly stage: string | |
| * }> {} | |
| * | |
| * // Create a channel | |
| * const dataChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // Attach exit handler | |
| * const channelWithExit = Channel.onExit(dataChannel, (exit) => { | |
| * if (Exit.isSuccess(exit)) { | |
| * return Console.log(`Channel completed successfully with: ${exit.value}`) | |
| * } else { | |
| * return Console.log(`Channel failed with: ${exit.cause}`) | |
| * } | |
| * }) | |
| * ``` | |
| * | |
| * @category resource management | |
| * @since 4.0.0 | |
| */ | |
| export const onExit = /*#__PURE__*/dual(2, (self, finalizer) => fromTransformBracket((upstream, scope, forkedScope) => Scope.addFinalizerExit(forkedScope, finalizer).pipe(Effect.andThen(toTransform(self)(upstream, scope))))); | |
| /** | |
| * Runs an effect before the channel starts. | |
| * | |
| * **Details** | |
| * | |
| * The effect's successful value is ignored. If the effect fails, the returned | |
| * channel fails before running the source channel. | |
| * | |
| * @category hooks | |
| * @since 4.0.0 | |
| */ | |
| export const onStart = /*#__PURE__*/dual(2, (self, onStart) => unwrap(Effect.as(onStart, self))); | |
| /** | |
| * Runs an effect the first time the channel emits an output element. | |
| * | |
| * **When to use** | |
| * | |
| * Use when initialization depends on the first output element rather than only | |
| * on channel startup. | |
| * | |
| * **Details** | |
| * | |
| * The effect receives the first emitted element. The first element is still | |
| * emitted unchanged. The effect is not run if the channel completes without | |
| * emitting an element. | |
| * | |
| * @category hooks | |
| * @since 4.0.0 | |
| */ | |
| export const onFirst = /*#__PURE__*/dual(2, (self, onFirst) => transformPull(self, pull => Effect.sync(() => { | |
| let isFirst = true; | |
| const pullFirst = Effect.tap(pull, element => { | |
| isFirst = false; | |
| return onFirst(element); | |
| }); | |
| return Effect.suspend(() => isFirst ? pullFirst : pull); | |
| }))); | |
| /** | |
| * Runs an effect when the channel completes successfully. | |
| * | |
| * **Details** | |
| * | |
| * The effect runs before the original done value is propagated. The effect is | |
| * not run when the channel fails. If the effect fails, the returned channel | |
| * fails with that error. | |
| * | |
| * @category hooks | |
| * @since 4.0.0 | |
| */ | |
| export const onEnd = /*#__PURE__*/dual(2, (self, onEnd) => transformPull(self, pull => Effect.succeed(Pull.catchDone(pull, leftover => Effect.flatMap(onEnd, () => Cause.done(leftover)))))); | |
| /** | |
| * Returns a channel with a finalizer effect that is guaranteed to run once the | |
| * channel begins execution, whether it succeeds or fails. | |
| * | |
| * **Example** (Ensuring cleanup runs) | |
| * | |
| * ```ts | |
| * import { Channel, Console, Data } from "effect" | |
| * | |
| * class EnsureError extends Data.TaggedError("EnsureError")<{ | |
| * readonly operation: string | |
| * }> {} | |
| * | |
| * // Create a channel | |
| * const dataChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // Ensure cleanup always runs | |
| * const channelWithCleanup = Channel.ensuring( | |
| * dataChannel, | |
| * Console.log("Cleanup executed regardless of success or failure") | |
| * ) | |
| * ``` | |
| * | |
| * @category resource management | |
| * @since 2.0.0 | |
| */ | |
| export const ensuring = /*#__PURE__*/dual(2, (self, finalizer) => onExit(self, _ => finalizer)); | |
| const runWith = (self, f, onHalt) => Effect.suspend(() => { | |
| const scope = Scope.makeUnsafe(); | |
| const makePull = toTransform(self)(Cause.done(), scope); | |
| return Pull.catchDone(Effect.flatMap(makePull, f), onHalt ? onHalt : Effect.succeed).pipe(Effect.onExit(exit => Scope.close(scope, exit))); | |
| }); | |
| /** | |
| * Creates a channel from the specified services. | |
| * | |
| * @category services | |
| * @since 2.0.0 | |
| */ | |
| export const contextWith = f => fromTransform((upstream, scope) => Effect.contextWith(context => toTransform(f(context))(upstream, scope))); | |
| /** | |
| * Provides a `Context` to the channel, removing the corresponding service | |
| * requirements from the returned channel. | |
| * | |
| * @category services | |
| * @since 2.0.0 | |
| */ | |
| export const provideContext = /*#__PURE__*/dual(2, (self, context) => fromTransform((upstream, scope) => Effect.map(Effect.provideContext(toTransform(self)(upstream, scope), context), Effect.provideContext(context)))); | |
| /** | |
| * Provides a concrete service for a context key, removing that service | |
| * requirement from the returned channel. | |
| * | |
| * @category services | |
| * @since 2.0.0 | |
| */ | |
| export const provideService = /*#__PURE__*/dual(3, (self, key, service) => fromTransform((upstream, scope) => Effect.map(Effect.provideService(toTransform(self)(upstream, scope), key, service), Effect.provideService(key, service)))); | |
| /** | |
| * Provides a service to the channel after obtaining it from an effect. | |
| * | |
| * **When to use** | |
| * | |
| * Use to supply a channel dependency when constructing the service itself is | |
| * effectful or can fail. | |
| * | |
| * **Details** | |
| * | |
| * If the service effect fails, the returned channel fails. The provided service | |
| * removes the corresponding service requirement from the returned channel. | |
| * | |
| * @category services | |
| * @since 4.0.0 | |
| */ | |
| export const provideServiceEffect = /*#__PURE__*/dual(3, (self, key, service) => fromTransform((upstream, scope) => Effect.flatMap(service, s => toTransform(provideService(self, key, s))(upstream, scope)))); | |
| /** | |
| * Provides a `Layer` or `Context` to the channel, removing the corresponding | |
| * service requirements. | |
| * | |
| * **Details** | |
| * | |
| * Providing a `Context` delegates to `provideContext`. Providing a `Layer` | |
| * builds the layer in the channel scope. Use `options.local` to build a fresh | |
| * layer instance for this provision. | |
| * | |
| * @category services | |
| * @since 4.0.0 | |
| */ | |
| export const provide = /*#__PURE__*/dual(args => isChannel(args[0]), (self, layer, options) => Context.isContext(layer) ? provideContext(self, layer) : fromTransform((upstream, scope) => Effect.flatMap(options?.local ? Layer.buildWithMemoMap(layer, Layer.makeMemoMapUnsafe(), scope) : Layer.buildWithScope(layer, scope), context => Effect.map(Effect.provideContext(toTransform(self)(upstream, scope), context), Effect.provideContext(context))))); | |
| /** | |
| * Transforms the current context before running the channel. | |
| * | |
| * **Details** | |
| * | |
| * The function receives the surrounding context and returns the context to | |
| * provide to the channel. The returned channel requires the services needed to | |
| * build that context. | |
| * | |
| * @category services | |
| * @since 4.0.0 | |
| */ | |
| export const updateContext = /*#__PURE__*/dual(2, (self, f) => fromTransform((upstream, scope) => Effect.contextWith(context => { | |
| const toProvide = f(context); | |
| return toTransform(provideContext(self, toProvide))(upstream, scope); | |
| }))); | |
| /** | |
| * Updates a service in the current context before running the channel. | |
| * | |
| * **Details** | |
| * | |
| * The existing service is read from the context. The updated service is | |
| * provided to the channel under the same key. | |
| * | |
| * @category services | |
| * @since 2.0.0 | |
| */ | |
| export const updateService = /*#__PURE__*/dual(3, (self, service, f) => updateContext(self, context => Context.add(context, service, f(Context.get(context, service))))); | |
| /** | |
| * Runs the channel inside a tracing span with the specified name and options. | |
| * | |
| * **Details** | |
| * | |
| * The created span is provided as the current parent span while the channel | |
| * runs. The span is ended with the channel's exit value. | |
| * | |
| * @category tracing | |
| * @since 2.0.0 | |
| */ | |
| export const withSpan = function () { | |
| const dataFirst = isChannel(arguments[0]); | |
| const name = dataFirst ? arguments[1] : arguments[0]; | |
| const options = addSpanStackTrace(dataFirst ? arguments[2] : arguments[1]); | |
| if (dataFirst) { | |
| const self = arguments[0]; | |
| return withSpanImpl(self, name, options); | |
| } | |
| return self => withSpanImpl(self, name, options); | |
| }; | |
| const withSpanImpl = (self, name, options) => acquireUseRelease(Effect.makeSpan(name, options), span => provideService(self, ParentSpan, span), (span, exit) => Effect.withFiber(fiber => { | |
| const clock = fiber.getRef(ClockRef); | |
| const timingEnabled = fiber.getRef(TracerTimingEnabled); | |
| return endSpan(span, exit, clock, timingEnabled); | |
| })); | |
| /** | |
| * The starting channel for Do notation, emitting an empty object. | |
| * | |
| * @category do notation | |
| * @since 4.0.0 | |
| */ | |
| export const Do = /*#__PURE__*/succeed({}); | |
| const let_ = /*#__PURE__*/dual(3, (self, name, f) => map(self, elem => ({ | |
| ...elem, | |
| [name]: f(elem) | |
| }))); | |
| export { | |
| /** | |
| * Adds a computed field to each object emitted by a channel. | |
| * | |
| * @category do notation | |
| * @since 4.0.0 | |
| */ | |
| let_ as let }; | |
| /** | |
| * Adds a field to each object emitted by a channel by running another channel | |
| * derived from that object. | |
| * | |
| * **Details** | |
| * | |
| * The field name must not already exist on the emitted object. The derived | |
| * channel's output becomes the value of the new field. `options.concurrency` | |
| * and `options.bufferSize` control how derived channels are flattened. | |
| * | |
| * @category do notation | |
| * @since 4.0.0 | |
| */ | |
| export const bind = /*#__PURE__*/dual(args => isChannel(args[0]), (self, name, f, options) => flatMap(self, elem => map(f(elem), b => ({ | |
| ...elem, | |
| [name]: b | |
| })), options)); | |
| /** | |
| * Wraps each output element in an object under the specified field name. | |
| * | |
| * **When to use** | |
| * | |
| * Use when you need to start a Channel Do-notation chain from an existing | |
| * output value by assigning that value to a field name. | |
| * | |
| * @see {@link Do} for starting Do notation from an empty object | |
| * @see {@link bind} for adding a field produced by another channel | |
| * @see {@link let_ let} for adding a computed field | |
| * | |
| * @category do notation | |
| * @since 4.0.0 | |
| */ | |
| export const bindTo = /*#__PURE__*/dual(2, (self, name) => map(self, elem => ({ | |
| [name]: elem | |
| }))); | |
| /** | |
| * Runs a channel and counts the number of elements it outputs. | |
| * | |
| * **Example** (Counting channel output) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class CountError extends Data.TaggedError("CountError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create a channel with multiple elements | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4, 5]) | |
| * | |
| * // Count the elements | |
| * const countEffect = Channel.runCount(numbersChannel) | |
| * | |
| * // Effect.runSync(countEffect) // Returns: 5 | |
| * ``` | |
| * | |
| * @category execution | |
| * @since 4.0.0 | |
| */ | |
| export const runCount = self => runFold(self, () => 0, acc => acc + 1); | |
| /** | |
| * Runs a channel and discards all output elements, returning only the final result. | |
| * | |
| * **Example** (Draining channel output at runtime) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class DrainError extends Data.TaggedError("DrainError")<{ | |
| * readonly stage: string | |
| * }> {} | |
| * | |
| * // Create a channel that outputs elements and completes with a result | |
| * const resultChannel = Channel.fromIterable([1, 2, 3]) | |
| * const completedChannel = Channel.concatWith( | |
| * resultChannel, | |
| * () => Channel.succeed("completed") | |
| * ) | |
| * | |
| * // Drain all elements and get only the final result | |
| * const drainEffect = Channel.runDrain(completedChannel) | |
| * | |
| * // Effect.runSync(drainEffect) // Returns: "completed" | |
| * ``` | |
| * | |
| * @category execution | |
| * @since 2.0.0 | |
| */ | |
| export const runDrain = self => runWith(self, pull => Effect.forever(pull, { | |
| disableYield: true | |
| })); | |
| /** | |
| * Runs a channel and applies an effect to each output element. | |
| * | |
| * **Example** (Running effects for each output) | |
| * | |
| * ```ts | |
| * import { Channel, Console, Data } from "effect" | |
| * | |
| * class ForEachError extends Data.TaggedError("ForEachError")<{ | |
| * readonly element: unknown | |
| * }> {} | |
| * | |
| * // Create a channel with numbers | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // Run forEach to log each element | |
| * const forEachEffect = Channel.runForEach( | |
| * numbersChannel, | |
| * (n) => Console.log(`Processing: ${n}`) | |
| * ) | |
| * | |
| * // Logs: "Processing: 1", "Processing: 2", "Processing: 3" | |
| * ``` | |
| * | |
| * @category execution | |
| * @since 4.0.0 | |
| */ | |
| export const runForEach = /*#__PURE__*/dual(2, (self, f) => runWith(self, pull => Effect.forever(Effect.flatMap(pull, f), { | |
| disableYield: true | |
| }))); | |
| /** | |
| * Runs a channel and applies an effectful predicate to each output element | |
| * until the predicate returns `false`. | |
| * | |
| * **Details** | |
| * | |
| * Returning `true` continues consuming the channel. Returning `false` stops | |
| * consumption early. The returned effect completes with `void`. | |
| * | |
| * @category execution | |
| * @since 4.0.0 | |
| */ | |
| export const runForEachWhile = /*#__PURE__*/dual(2, (self, f) => runWith(self, pull => pull.pipe(Effect.flatMap(f), Effect.flatMap(cont => cont ? Effect.void : Cause.done()), Effect.forever({ | |
| disableYield: true | |
| })))); | |
| /** | |
| * Runs a channel and collects all output elements into an array. | |
| * | |
| * **Example** (Collecting channel output) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class CollectError extends Data.TaggedError("CollectError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create a channel with elements | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4, 5]) | |
| * | |
| * // Collect all elements into an array | |
| * const collectEffect = Channel.runCollect(numbersChannel) | |
| * | |
| * // Effect.runSync(collectEffect) // Returns: [1, 2, 3, 4, 5] | |
| * ``` | |
| * | |
| * @category execution | |
| * @since 2.0.0 | |
| */ | |
| export const runCollect = self => runFold(self, () => [], (acc, o) => { | |
| acc.push(o); | |
| return acc; | |
| }); | |
| /** | |
| * Runs a channel and outputs the done value. | |
| * | |
| * @category execution | |
| * @since 4.0.0 | |
| */ | |
| export const runDone = self => runWith(self, identity_, Effect.succeed); | |
| /** | |
| * Runs a channel until the first output element is available, returning it in | |
| * an `Option`. | |
| * | |
| * **Details** | |
| * | |
| * Returns `Option.some` with the first output element, or `Option.none` if the | |
| * channel completes without emitting output. | |
| * | |
| * @category execution | |
| * @since 4.0.0 | |
| */ | |
| export const runHead = self => Effect.suspend(() => { | |
| let head = Option.none(); | |
| return runWith(self, pull => pull.pipe(Effect.asSome, Effect.flatMap(head_ => { | |
| head = head_; | |
| return Cause.done(); | |
| })), () => Effect.succeed(head)); | |
| }); | |
| /** | |
| * Runs a channel to completion and returns the last output element in an | |
| * `Option`. | |
| * | |
| * **Details** | |
| * | |
| * Returns `Option.some` with the last emitted element, or `Option.none` if the | |
| * channel completes without emitting output. | |
| * | |
| * @category execution | |
| * @since 4.0.0 | |
| */ | |
| export const runLast = self => Effect.suspend(() => { | |
| const absent = Symbol(); // Prevent boxing | |
| let last = absent; | |
| return runWith(self, pull => Effect.forever(Effect.flatMap(pull, item => { | |
| last = item; | |
| return Effect.void; | |
| }), { | |
| disableYield: true | |
| }), () => last === absent ? Effect.succeedNone : Effect.succeedSome(last)); | |
| }); | |
| /** | |
| * Runs a channel and folds over all output elements with an accumulator. | |
| * | |
| * **Example** (Folding channel output) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class FoldError extends Data.TaggedError("FoldError")<{ | |
| * readonly operation: string | |
| * }> {} | |
| * | |
| * // Create a channel with numbers | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3, 4, 5]) | |
| * | |
| * // Fold to calculate sum | |
| * const sumEffect = Channel.runFold(numbersChannel, () => 0, (acc, n) => acc + n) | |
| * | |
| * // Effect.runSync(sumEffect) // Returns: 15 | |
| * ``` | |
| * | |
| * @category execution | |
| * @since 4.0.0 | |
| */ | |
| export const runFold = /*#__PURE__*/dual(3, (self, initial, f) => Effect.suspend(() => { | |
| let state = initial(); | |
| return runWith(self, pull => Effect.whileLoop({ | |
| while: constTrue, | |
| body: () => pull, | |
| step: value => { | |
| state = f(state, value); | |
| } | |
| }), () => Effect.succeed(state)); | |
| })); | |
| /** | |
| * Runs a channel and effectfully folds all output elements with an accumulator. | |
| * | |
| * **When to use** | |
| * | |
| * Use when folding channel output needs effects, services, or an additional | |
| * failure channel during accumulation. | |
| * | |
| * **Details** | |
| * | |
| * The initial accumulator is evaluated lazily. Each output element is passed to | |
| * the effectful accumulator function. The returned effect succeeds with the | |
| * final accumulator value. | |
| * | |
| * @category execution | |
| * @since 4.0.0 | |
| */ | |
| export const runFoldEffect = /*#__PURE__*/dual(3, (self, initial, f) => Effect.suspend(() => { | |
| let state = initial(); | |
| return runWith(self, pull => Effect.whileLoop({ | |
| while: constTrue, | |
| body: constant(pull.pipe(Effect.flatMap(o => f(state, o)), Effect.map(s => { | |
| state = s; | |
| }))), | |
| step: constVoid | |
| }), () => Effect.succeed(state)); | |
| })); | |
| /** | |
| * Converts a channel to a scoped `Pull` for low-level consumption. | |
| * | |
| * **Details** | |
| * | |
| * The effect requires a `Scope`. The returned pull should be consumed only | |
| * while that scope remains open. Pulls are serialized so only one pull is | |
| * evaluated at a time. | |
| * | |
| * **Example** (Converting channels to pulls) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect } from "effect" | |
| * | |
| * class PullError extends Data.TaggedError("PullError")<{ | |
| * readonly step: string | |
| * }> {} | |
| * | |
| * // Create a channel | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // Convert to Pull within a scope | |
| * const pullEffect = Effect.scoped( | |
| * Channel.toPull(numbersChannel) | |
| * ) | |
| * | |
| * // Use the Pull to manually consume elements | |
| * ``` | |
| * | |
| * @category destructors | |
| * @since 2.0.0 | |
| */ | |
| export const toPull = /*#__PURE__*/Effect.fnUntraced(function* (self) { | |
| const semaphore = Semaphore.makeUnsafe(1); | |
| const context = yield* Effect.context(); | |
| const scope = Context.get(context, Scope.Scope); | |
| const pull = yield* toTransform(self)(Cause.done(), scope); | |
| return pull.pipe(Effect.provideContext(context), semaphore.withPermits(1)); | |
| }, | |
| /*#__PURE__*/ | |
| // ensure errors are redirected to the pull effect | |
| Effect.catchCause(cause => Effect.succeed(Effect.failCause(cause)))); | |
| /** | |
| * Converts a channel to a Pull within an existing scope. | |
| * | |
| * **Example** (Converting channels to scoped pulls) | |
| * | |
| * ```ts | |
| * import { Channel, Data, Effect, Scope } from "effect" | |
| * | |
| * class ScopedPullError extends Data.TaggedError("ScopedPullError")<{ | |
| * readonly reason: string | |
| * }> {} | |
| * | |
| * // Create a channel | |
| * const numbersChannel = Channel.fromIterable([1, 2, 3]) | |
| * | |
| * // Convert to Pull with explicit scope | |
| * const scopedPullEffect = Effect.gen(function*() { | |
| * const scope = yield* Scope.make() | |
| * const pull = yield* Channel.toPullScoped(numbersChannel, scope) | |
| * return pull | |
| * }) | |
| * ``` | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const toPullScoped = (self, scope) => toTransform(self)(Cause.done(), scope); | |
| /** | |
| * 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`. | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const runIntoQueue = /*#__PURE__*/dual(args => isChannel(args[0]), (self, queue) => Effect.uninterruptibleMask(restore => runForEach(self, value => Queue.offer(queue, value)).pipe(restore, Effect.exit, Effect.flatMap(exit => { | |
| if (Exit.isSuccess(exit)) { | |
| Queue.endUnsafe(queue); | |
| } else { | |
| Queue.failCauseUnsafe(queue, exit.cause); | |
| } | |
| return Effect.void; | |
| })))); | |
| /** | |
| * Runs a channel that emits non-empty arrays and offers each array 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`. | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const runIntoQueueArray = /*#__PURE__*/dual(args => isChannel(args[0]), (self, queue) => Effect.uninterruptibleMask(restore => runForEach(self, value => Queue.offerAll(queue, value)).pipe(restore, Effect.exit, Effect.flatMap(exit => { | |
| if (Exit.isSuccess(exit)) { | |
| Queue.endUnsafe(queue); | |
| } else { | |
| Queue.failCauseUnsafe(queue, exit.cause); | |
| } | |
| return Effect.void; | |
| })))); | |
| /** | |
| * Creates a scoped queue and forks the channel to feed it for concurrent | |
| * consumption. | |
| * | |
| * **Details** | |
| * | |
| * Output elements are offered to the queue. Channel completion and failure are | |
| * signaled through the queue. The queue is shut down when the surrounding scope | |
| * closes. | |
| * | |
| * **Example** (Converting channels to queues) | |
| * | |
| * ```ts | |
| * import { Channel, Data } from "effect" | |
| * | |
| * class QueueError extends Data.TaggedError("QueueError")<{ | |
| * readonly operation: string | |
| * }> {} | |
| * | |
| * // Create a channel with data | |
| * const dataChannel = Channel.fromIterable([1, 2, 3, 4, 5]) | |
| * | |
| * // Convert to queue for concurrent processing | |
| * const queueEffect = Channel.toQueue(dataChannel, { capacity: 32 }) | |
| * | |
| * // The queue can be used for concurrent consumption | |
| * // Multiple consumers can read from the queue | |
| * ``` | |
| * | |
| * @category destructors | |
| * @since 2.0.0 | |
| */ | |
| export const toQueue = /*#__PURE__*/dual(args => isChannel(args[0]), /*#__PURE__*/Effect.fnUntraced(function* (self, options) { | |
| const scope = yield* Effect.scope; | |
| const queue = yield* Queue.make({ | |
| capacity: typeof options.capacity === "number" ? options.capacity : undefined, | |
| strategy: typeof options.capacity === "number" ? options.strategy : undefined | |
| }); | |
| yield* Scope.addFinalizer(scope, Queue.shutdown(queue)); | |
| yield* Effect.forkIn(runIntoQueue(self, queue), scope); | |
| return queue; | |
| })); | |
| /** | |
| * Creates a scoped queue and forks an array-emitting channel to feed it. | |
| * | |
| * **Details** | |
| * | |
| * Each element inside emitted non-empty arrays is offered to the queue. Channel | |
| * completion and failure are signaled through the queue. The queue is shut down | |
| * when the surrounding scope closes. | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const toQueueArray = /*#__PURE__*/dual(args => isChannel(args[0]), /*#__PURE__*/Effect.fnUntraced(function* (self, options) { | |
| const scope = yield* Effect.scope; | |
| const queue = yield* Queue.make({ | |
| capacity: typeof options.capacity === "number" ? options.capacity : undefined, | |
| strategy: typeof options.capacity === "number" ? options.strategy : undefined | |
| }); | |
| yield* Scope.addFinalizer(scope, Queue.shutdown(queue)); | |
| yield* Effect.forkIn(runIntoQueueArray(self, queue), scope); | |
| return queue; | |
| })); | |
| /** | |
| * Converts a channel to a PubSub for concurrent consumption. | |
| * | |
| * **Details** | |
| * | |
| * `shutdownOnEnd` indicates whether the PubSub should be shut down when the | |
| * channel ends. By default this is `true`. | |
| * | |
| * @category destructors | |
| * @since 2.0.0 | |
| */ | |
| export const toPubSub = /*#__PURE__*/dual(2, /*#__PURE__*/Effect.fnUntraced(function* (self, options) { | |
| const pubsub = yield* makePubSub(options); | |
| yield* Effect.forkScoped(runIntoPubSub(self, pubsub, { | |
| shutdownOnEnd: options.shutdownOnEnd !== false | |
| })); | |
| return pubsub; | |
| })); | |
| /** | |
| * Runs a channel and publishes each output element to a `PubSub`. | |
| * | |
| * **Details** | |
| * | |
| * The channel's output values are published as individual PubSub messages. Use | |
| * `options.shutdownOnEnd` to shut down the PubSub when channel execution ends. | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const runIntoPubSub = /*#__PURE__*/dual(args => isChannel(args[0]), (self, pubsub, options) => runForEach(self, value => PubSub.publish(pubsub, value)).pipe(options?.shutdownOnEnd === true ? Effect.ensuring(PubSub.shutdown(pubsub)) : identity_)); | |
| const makePubSub = options => Effect.acquireRelease(options.capacity === "unbounded" ? PubSub.unbounded(options) : options.strategy === "dropping" ? PubSub.dropping(options) : options.strategy === "sliding" ? PubSub.sliding(options) : PubSub.bounded(options), PubSub.shutdown); | |
| /** | |
| * Converts an array-emitting channel to a scoped `PubSub` for concurrent | |
| * consumption. | |
| * | |
| * **Details** | |
| * | |
| * Each element inside emitted non-empty arrays is published as an individual | |
| * PubSub message. `shutdownOnEnd` indicates whether the PubSub should be shut | |
| * down when the channel ends. By default this is `true`. | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const toPubSubArray = /*#__PURE__*/dual(2, /*#__PURE__*/Effect.fnUntraced(function* (self, options) { | |
| const pubsub = yield* makePubSub(options); | |
| yield* Effect.forkScoped(runIntoPubSubArray(self, pubsub, { | |
| shutdownOnEnd: options.shutdownOnEnd !== false | |
| })); | |
| return pubsub; | |
| })); | |
| /** | |
| * Runs an array-emitting channel and publishes each array element to a | |
| * `PubSub`. | |
| * | |
| * **Details** | |
| * | |
| * Each element inside emitted non-empty arrays is published as an individual | |
| * PubSub message. Use `options.shutdownOnEnd` to shut down the PubSub when | |
| * channel execution ends. | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const runIntoPubSubArray = /*#__PURE__*/dual(args => isChannel(args[0]), (self, pubsub, options) => runForEach(self, value => PubSub.publishAll(pubsub, value)).pipe(options?.shutdownOnEnd === true ? Effect.ensuring(PubSub.shutdown(pubsub)) : identity_)); | |
| /** | |
| * Converts a channel to a scoped `PubSub` of `Take` values. | |
| * | |
| * **Details** | |
| * | |
| * Emitted non-empty arrays are published as output `Take` values. When the | |
| * channel ends, its final `Exit` is published so subscribers can observe | |
| * completion or failure. | |
| * | |
| * @category destructors | |
| * @since 4.0.0 | |
| */ | |
| export const toPubSubTake = /*#__PURE__*/dual(2, /*#__PURE__*/Effect.fnUntraced(function* (self, options) { | |
| const pubsub = yield* makePubSub(options); | |
| yield* runForEach(self, value => PubSub.publish(pubsub, value)).pipe(Effect.onExit(exit => PubSub.publish(pubsub, exit)), Effect.forkScoped); | |
| return pubsub; | |
| })); | |
| //# sourceMappingURL=Channel.js.map |
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