<A, E = never>(a: A): Result<Option<A>, E>Creates a Result<Option<A>> that succeeds with Some(a).
Details
- Equivalent to
Result.succeed(Option.some(a)) - Useful with transposeOption patterns
Example (Wrapping a value in Some inside a Result)
import { Result } from "effect"
const result = Result.succeedSome(42)
console.log(result)
// Output: { _tag: "Success", success: { _tag: "Some", value: 42 }, ... }Source effect/Result.ts:18961 lines
export const const succeedSome: <A, E = never>(
a: A
) => Result<Option<A>, E>
Creates a Result<Option<A>> that succeeds with Some(a).
Details
- Equivalent to
Result.succeed(Option.some(a))
- Useful with
transposeOption
patterns
Example (Wrapping a value in Some inside a Result)
import { Result } from "effect"
const result = Result.succeedSome(42)
console.log(result)
// Output: { _tag: "Success", success: { _tag: "Some", value: 42 }, ... }
succeedSome = <function (type parameter) A in <A, E = never>(a: A): Result<Option<A>, E>A, function (type parameter) E in <A, E = never>(a: A): Result<Option<A>, E>E = never>(a: Aa: function (type parameter) A in <A, E = never>(a: A): Result<Option<A>, E>A): type Result<A, E = never> = Success<A, E> | Failure<A, E>A value that is either Success<A, E> or Failure<A, E>.
When to use
Use when both success and failure should remain available as data and
Option would lose failure information.
Details
- Use
succeed
/
fail
to construct
- Use
match
to fold both branches
- Use
isSuccess
/
isFailure
to narrow the type
E defaults to never, so Result<number> means a result that cannot fail.
Example (Creating and matching a Result)
import { Result } from "effect"
const success = Result.succeed(42)
const failure = Result.fail("something went wrong")
const message = Result.match(success, {
onSuccess: (value) => `Success: ${value}`,
onFailure: (error) => `Error: ${error}`
})
console.log(message)
// Output: "Success: 42"
Namespace containing type-level utilities for extracting the inner types
of a Result.
Example (Extracting inner types)
import type { Result } from "effect"
type R = Result.Result<number, string>
// number
type A = Result.Result.Success<R>
// string
type E = Result.Result.Failure<R>
Result<import OptionOption<function (type parameter) A in <A, E = never>(a: A): Result<Option<A>, E>A>, function (type parameter) E in <A, E = never>(a: A): Result<Option<A>, E>E> => const succeed: <A>(right: A) => Result<A>Creates a Result holding a Success value.
Details
- Use when you have a value and want to lift it into the
Result type
- The error type
E defaults to never
Example (Wrapping a value)
import { Result } from "effect"
const result = Result.succeed(42)
console.log(Result.isSuccess(result))
// Output: true
succeed(import option_option_.const some: <A>(
value: A
) => Option.Option<A>
a: Aa))