effect-io-ai

Package: effect
Module: Effect

Effect.timeoutFailCause

Specifies a custom defect to be thrown when a timeout occurs.

Details

This function allows you to handle timeouts as exceptional cases by generating a custom defect when an effect exceeds the specified duration. You provide:

• A duration: The time limit for the effect.
• An onTimeout function: A lazy evaluation function that generates the custom defect (typically created using Cause.die).

If the effect completes within the time limit, its result is returned normally. Otherwise, the custom defect is triggered, and the effect fails with that defect.

When to Use

This is especially useful when you need to treat timeouts as critical failures in your application and wish to include meaningful information in the defect.

Example

import { Effect, Cause } from "effect"

const task = Effect.gen(function* () {
  console.log("Start processing...")
  yield* Effect.sleep("2 seconds") // Simulates a delay in processing
  console.log("Processing complete.")
  return "Result"
})

const program = task.pipe(
  Effect.timeoutFailCause({
    duration: "1 second",
    onTimeout: () => Cause.die("Timed out!") // Custom defect for timeout
  })
)

Effect.runPromiseExit(program).then(console.log)
// Output:
// Start processing...
// {
//   _id: 'Exit',
//   _tag: 'Failure',
//   cause: { _id: 'Cause', _tag: 'Die', defect: 'Timed out!' }
// }

See

• timeout for a version that raises a TimeoutException.
• timeoutFail for a version that raises a custom error.
• timeoutTo for a version that allows specifying both success and timeout handlers.

Signature

declare const timeoutFailCause: { <E1>(options: { readonly onTimeout: LazyArg<Cause.Cause<E1>>; readonly duration: Duration.DurationInput; }): <A, E, R>(self: Effect<A, E, R>) => Effect<A, E1 | E, R>; <A, E, R, E1>(self: Effect<A, E, R>, options: { readonly onTimeout: LazyArg<Cause.Cause<E1>>; readonly duration: Duration.DurationInput; }): Effect<A, E | E1, R>; }

Source

Since v2.0.0