effect-io-ai

Package: effect
Module: Effect

Effect.result

Converts both success and failure of an Effect into a Result type.

When to use

Use when you want an Effect’s typed failures to be handled as Result data while preserving the original error value.

Details

This function converts an effect that may fail into an effect that always succeeds, wrapping the outcome in a Result type. The result will be Result.Failure if the effect fails, containing the recoverable error, or Result.Success if it succeeds, containing the result.

Using this function, you can handle recoverable errors explicitly without causing the effect to fail. This is particularly useful in scenarios where you want to chain effects and manage both success and failure in the same logical flow.

The resulting effect cannot fail directly because all recoverable failures are represented inside the Result type.

Gotchas

result only captures typed, recoverable failures. Defects and interruptions are not captured inside the Result and still fail the effect.

Example (Capturing success or failure as Result)

import { Effect } from "effect"

const success = Effect.succeed(42)
const failure = Effect.fail("Something went wrong")

const program1 = Effect.result(success)
const program2 = Effect.result(failure)

Effect.runPromise(program1).then(console.log)
// { _id: 'Result', _tag: 'Success', value: 42 }

Effect.runPromise(program2).then(console.log)
// { _id: 'Result', _tag: 'Failure', error: 'Something went wrong' }

See

• option for a version that uses Option instead.
• exit for a version that encapsulates both recoverable errors and defects in an Exit.

Signature

declare const result: <A, E, R>(self: Effect<A, E, R>) => Effect<Result.Result<A, E>, never, R>

Source

Since v4.0.0