effect-io-ai

Package: effect
Module: Effect

Effect.timeoutTo

Provides custom behavior for successful and timed-out operations.

Details

This function allows you to define distinct outcomes for an effect depending on whether it completes within a specified time frame or exceeds the timeout duration. You can provide:

• onSuccess: A handler for processing the result of the effect if it completes successfully within the time limit.
• onTimeout: A handler for generating a result when the effect times out.
• duration: The maximum allowed time for the effect to complete.

When to Use

Unlike timeout, which raises an exception for timeouts, this function gives you full control over the behavior for both success and timeout scenarios. It is particularly useful when you want to encapsulate timeouts and successes into a specific data structure, like an Either type, to represent these outcomes in a meaningful way.

Example

import { Effect, Either } 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.timeoutTo({
    duration: "1 second",
    onSuccess: (result): Either.Either<string, string> =>
      Either.right(result),
    onTimeout: (): Either.Either<string, string> =>
      Either.left("Timed out!")
  })
)

Effect.runPromise(program).then(console.log)
// Output:
// Start processing...
// {
//   _id: "Either",
//   _tag: "Left",
//   left: "Timed out!"
// }

See

• timeout for a version that raises a TimeoutException.
• timeoutFail for a version that raises a custom error.
• timeoutFailCause for a version that raises a custom defect.

Signature

declare const timeoutTo: { <A, B, B1>(options: { readonly onTimeout: LazyArg<B1>; readonly onSuccess: (a: A) => B; readonly duration: Duration.DurationInput; }): <E, R>(self: Effect<A, E, R>) => Effect<B | B1, E, R>; <A, E, R, B1, B>(self: Effect<A, E, R>, options: { readonly onTimeout: LazyArg<B1>; readonly onSuccess: (a: A) => B; readonly duration: Duration.DurationInput; }): Effect<B1 | B, E, R>; }

Source

Since v2.0.0