<Output, Input, Error, Env>(
schedule: Schedule<Output, Input, Error, Env>
): Effect<
(
input: Input
) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>,
never,
Env
>Extracts a step function from a Schedule that sleeps for each computed
delay and returns metadata for the completed step.
When to use
Use to drive a schedule manually while preserving the computed output, delay, input, attempt, and elapsed timing metadata for each step.
Details
The returned step reads the current time from Clock when invoked, calls the
schedule step with that timestamp and input, sleeps for the returned
duration, and then yields Metadata.
Source effect/Schedule.ts:40228 lines
export const const toStepWithMetadata: <
Output,
Input,
Error,
Env
>(
schedule: Schedule<Output, Input, Error, Env>
) => Effect<
(
input: Input
) => Pull.Pull<
Metadata<Output, Input>,
Error,
Output,
Env
>,
never,
Env
>
Extracts a step function from a Schedule that sleeps for each computed
delay and returns metadata for the completed step.
When to use
Use to drive a schedule manually while preserving the computed output,
delay, input, attempt, and elapsed timing metadata for each step.
Details
The returned step reads the current time from Clock when invoked, calls the
schedule step with that timestamp and input, sleeps for the returned
duration, and then yields Metadata.
toStepWithMetadata = <function (type parameter) Output in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Output, function (type parameter) Input in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Input, function (type parameter) Error in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Error, function (type parameter) Env in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Env>(
schedule: Schedule<Output, Input, Error, Env>(parameter) schedule: {
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
interface Schedule<out Output, in Input = unknown, out Error = never, out Env = never>A Schedule defines a strategy for repeating or retrying effects based on some policy.
Example (Defining retry and repeat schedules)
import { Console, Data, Effect, Schedule } from "effect"
class NetworkError extends Data.TaggedError("NetworkError")<{
readonly attempt: number
}> {}
// Basic retry schedule - retry up to 3 times with exponential backoff
const retrySchedule = Schedule.max([
Schedule.exponential("100 millis"),
Schedule.recurs(3)
])
// Basic repeat schedule - repeat every 30 seconds forever
const repeatSchedule: Schedule.Schedule<number, unknown, never> = Schedule
.spaced("30 seconds")
const program = Effect.gen(function*() {
let attempts = 0
const result1 = yield* Effect.retry(
Effect.gen(function*() {
attempts++
if (attempts < 3) {
return yield* Effect.fail(new NetworkError({ attempt: attempts }))
}
return "Success"
}),
retrySchedule
)
console.log(result1) // "Success"
yield* Console.log("heartbeat").pipe(
Effect.repeat(repeatSchedule.pipe(Schedule.upTo({ times: 5 })))
)
})
The Schedule namespace contains types and utilities for working with schedules.
Schedule<function (type parameter) Output in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Output, function (type parameter) Input in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Input, function (type parameter) Error in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Error, function (type parameter) Env in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Env>
): import EffectEffect<
(input: Inputinput: function (type parameter) Input in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Input) => import PullPull.type Pull.Pull = /*unresolved*/ anyPull<interface Metadata<Output = unknown, Input = unknown>Extended metadata that includes both input metadata and the output value from the schedule.
Metadata<function (type parameter) Output in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Output, function (type parameter) Input in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Input>, function (type parameter) Error in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Error, function (type parameter) Output in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Output, function (type parameter) Env in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Env>,
never,
function (type parameter) Env in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Env
> =>
import effecteffect.const clockWith: <A, E, R>(
f: (
clock: Clock.Clock
) => Effect.Effect<A, E, R>
) => Effect.Effect<A, E, R>
clock: Clock(parameter) clock: {
currentTimeMillisUnsafe: () => number;
currentTimeMillis: Effect<number>;
currentTimeNanosUnsafe: () => bigint;
currentTimeNanos: Effect<bigint>;
sleep: (duration: Duration.Duration) => Effect<void>;
}
import effecteffect.const map: {
<A, B>(f: (a: A) => B): <E, R>(
self: Effect.Effect<A, E, R>
) => Effect.Effect<B, E, R>
<A, E, R, B>(
self: Effect.Effect<A, E, R>,
f: (a: A) => B
): Effect.Effect<B, E, R>
}
const toStep: <Output, Input, Error, Env>(
schedule: Schedule<Output, Input, Error, Env>
) => Effect<
(
now: number,
input: Input
) => Pull.Pull<
[Output, Duration.Duration],
Error,
Output,
Env
>,
never,
Env
>
Extracts the step function from a Schedule.
Example (Extracting a schedule step function)
import { Effect, Schedule } from "effect"
// Extract step function from an existing schedule
const schedule = Schedule.exponential("100 millis").pipe(Schedule.upTo({ times: 3 }))
const program = Effect.gen(function*() {
const stepFn = yield* Schedule.toStep(schedule)
// Use the step function directly for custom logic. The timestamp is
// supplied by the caller, so tests can pass a deterministic value.
const now = 0
const result = yield* stepFn(now, "input")
console.log(`Step result: ${result}`)
})
toStep(schedule: Schedule<Output, Input, Error, Env>(parameter) schedule: {
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
step: unknownstep) => {
const const metaFn: <In>(
now: number,
input: In
) => InputMetadata<In>
const metadataFn: () => <In>(
now: number,
input: In
) => InputMetadata<In>
input: anyinput) =>
import effecteffect.const suspend: <A, E, R>(
evaluate: LazyArg<Effect.Effect<A, E, R>>
) => Effect.Effect<A, E, R>
const now: anynow = clock: Clock(parameter) clock: {
currentTimeMillisUnsafe: () => number;
currentTimeMillis: Effect<number>;
currentTimeNanosUnsafe: () => bigint;
currentTimeNanos: Effect<bigint>;
sleep: (duration: Duration.Duration) => Effect<void>;
}
import effecteffect.const flatMap: {
<A, B, E2, R2>(
f: (a: A) => Effect.Effect<B, E2, R2>
): <E, R>(
self: Effect.Effect<A, E, R>
) => Effect.Effect<B, E | E2, R | R2>
<A, E, R, B, E2, R2>(
self: Effect.Effect<A, E, R>,
f: (a: A) => Effect.Effect<B, E2, R2>
): Effect.Effect<B, E | E2, R | R2>
}
step: unknownstep(const now: anynow, input: anyinput),
([output: anyoutput, duration: Duration.Duration(parameter) duration: {
value: DurationValue;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
const meta: Mutable<
Metadata<Output, Input>
>
const meta: {
output: Output;
duration: Duration.Duration;
input: Input;
attempt: number;
start: number;
now: number;
elapsed: number;
elapsedSincePrevious: number;
}
const metaFn: <In>(
now: number,
input: In
) => InputMetadata<In>
const now: anynow, input: anyinput) as type Mutable<T> = { -readonly [P in keyof T]: T[P]; }Removes readonly from all properties of T. Supports arrays, tuples,
and records.
When to use
Use when you need a mutable version of a readonly type.
Details
Only affects the top level; nested properties remain readonly.
Example (Converting shallowly to mutable types)
import type { Types } from "effect"
type Obj = Types.Mutable<{
readonly a: string
readonly b: ReadonlyArray<number>
}>
// { a: string; b: ReadonlyArray<number> }
// ^ mutable ^ still readonly inside
type Arr = Types.Mutable<ReadonlyArray<string>>
// string[]
type Tup = Types.Mutable<readonly [string, number]>
// [string, number]
Mutable<interface Metadata<Output = unknown, Input = unknown>Extended metadata that includes both input metadata and the output value from the schedule.
Metadata<function (type parameter) Output in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Output, function (type parameter) Input in <Output, Input, Error, Env>(schedule: Schedule<Output, Input, Error, Env>): Effect<(input: Input) => Pull.Pull<Metadata<Output, Input>, Error, Output, Env>, never, Env>Input>>
const meta: Mutable<
Metadata<Output, Input>
>
const meta: {
output: Output;
duration: Duration.Duration;
input: Input;
attempt: number;
start: number;
now: number;
elapsed: number;
elapsedSincePrevious: number;
}
output: Outputoutput = output: anyoutput
const meta: Mutable<
Metadata<Output, Input>
>
const meta: {
output: Output;
duration: Duration.Duration;
input: Input;
attempt: number;
start: number;
now: number;
elapsed: number;
elapsedSincePrevious: number;
}
duration: Duration.Duration(property) duration: {
value: DurationValue;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
duration: Duration.Duration(parameter) duration: {
value: DurationValue;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
import effecteffect.const as: {
<A, B>(value: B): <E, R>(
self: Effect.Effect<A, E, R>
) => Effect.Effect<B, E, R>
<A, E, R, B>(
self: Effect.Effect<A, E, R>,
value: B
): Effect.Effect<B, E, R>
}
import effecteffect.const sleep: (
duration: Duration.Input
) => Effect.Effect<void>
duration: Duration.Duration(parameter) duration: {
value: DurationValue;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
const meta: Mutable<
Metadata<Output, Input>
>
const meta: {
output: Output;
duration: Duration.Duration;
input: Input;
attempt: number;
start: number;
now: number;
elapsed: number;
elapsedSincePrevious: number;
}
Referenced by 4 symbols