effect-io-ai

Package: effect
Module: Result

Result.map

Transforms the success channel of a Result, leaving the failure channel unchanged.

When to use

Use to apply a transformation to the success value of a Result while preserving any existing failure.

Details

• If the result is a Success, applies f to the value and returns a new Success
• If the result is a Failure, returns it as-is
• Use flatMap if f returns a Result (to avoid nested Results)

Example (Doubling the success value)

import { pipe, Result } from "effect"

const result = pipe(
  Result.succeed(3),
  Result.map((n) => n * 2)
)
console.log(result)
// Output: { _tag: "Success", success: 6, ... }

See

• mapError to transform only the error value
• mapBoth to transform both channels
• flatMap when f returns a Result

Signature

declare const map: { <A, A2>(f: (ok: A) => A2): <E>(self: Result<A, E>) => Result<A2, E>; <A, E, A2>(self: Result<A, E>, f: (ok: A) => A2): Result<A2, E>; }

Source

Since v2.0.0