Class AsyncResult<T, E>

Type Parameters

Index

Constructors

constructor

new AsyncResult<T, E>(promise: Promise<Result<T, E>>): AsyncResult<T, E>
Type Parameters
- T
- E
Parameters
- promise: Promise<Result<T, E>>
Returns AsyncResult<T, E>
- Defined in src/result/result/asyncResult.ts:15

Properties

`Protected` `Readonly`promise

promise: Promise<Result<T, E>>

Methods

[asyncIterator]

"[asyncIterator]"(): AsyncGenerator<Err<E>, T>
Enables yield* asyncRes inside an async result.gen / result.genAsync body: awaits the underlying Result, then behaves like its sync counterpart — evaluates to the Ok value or short-circuits the body with the Err. Equivalent to yield* (await asyncRes).

Returns AsyncGenerator<Err<E>, T>
- Defined in src/result/result/asyncResult.ts:101

and

and<R2 extends ResultLike<R2>>(
res: R2 | PromiseLike<R2>,
): AsyncResult<OkContent<R2>, E | ErrContent<R2>>
Type Parameters
- R2 extends ResultLike<R2>
Parameters
- res: R2 | PromiseLike<R2>
Returns AsyncResult<OkContent<R2>, E | ErrContent<R2>>
- Defined in src/result/result/asyncResult.ts:47

andThen

andThen<R2 extends ResultLike<R2>>(
fn: (value: T) => R2 | PromiseLike<R2>,
): AsyncResult<OkContent<R2>, E | ErrContent<R2>>
Type Parameters
- R2 extends ResultLike<R2>
Parameters
- fn: (value: T) => R2 | PromiseLike<R2>
Returns AsyncResult<OkContent<R2>, E | ErrContent<R2>>
- Defined in src/result/result/asyncResult.ts:53

inspect

inspect(fn: (value: DeepReadonly<T>) => void | Promise<void>): AsyncResult<T, E>
Parameters
- fn: (value: DeepReadonly<T>) => void | Promise<void>
Returns AsyncResult<T, E>
- Defined in src/result/result/asyncResult.ts:81

inspectErr

inspectErr(
fn: (error: DeepReadonly<E>) => void | Promise<void>,
): AsyncResult<T, E>
Parameters
- fn: (error: DeepReadonly<E>) => void | Promise<void>
Returns AsyncResult<T, E>
- Defined in src/result/result/asyncResult.ts:88

map

map<T2>(fn: (value: T) => T2 | Promise<T2>): AsyncResult<T2, E>
Type Parameters
- T2
Parameters
- fn: (value: T) => T2 | Promise<T2>
Returns AsyncResult<T2, E>
- Defined in src/result/result/asyncResult.ts:39

mapErr

mapErr<E2>(fn: (error: E) => E2 | Promise<E2>): AsyncResult<T, E2>
Type Parameters
- E2
Parameters
- fn: (error: E) => E2 | Promise<E2>
Returns AsyncResult<T, E2>
- Defined in src/result/result/asyncResult.ts:43

or

or<R2 extends ResultLike<R2>>(
res: R2 | PromiseLike<R2>,
): AsyncResult<T | OkContent<R2>, ErrContent<R2>>
Type Parameters
- R2 extends ResultLike<R2>
Parameters
- res: R2 | PromiseLike<R2>
Returns AsyncResult<T | OkContent<R2>, ErrContent<R2>>
- Defined in src/result/result/asyncResult.ts:59

orElse

orElse<R2 extends ResultLike<R2>>(
fn: (error: E) => R2 | PromiseLike<R2>,
): AsyncResult<T | OkContent<R2>, ErrContent<R2>>
Type Parameters
- R2 extends ResultLike<R2>
Parameters
- fn: (error: E) => R2 | PromiseLike<R2>
Returns AsyncResult<T | OkContent<R2>, ErrContent<R2>>
- Defined in src/result/result/asyncResult.ts:65

then

then<TResult1 = Result<T, E>, TResult2 = never>(
    onfulfilled?:
        | ((value: Result<T, E>) => TResult1 | PromiseLike<TResult1>)
        | null,
    onrejected?: ((reason: unknown) => TResult2 | PromiseLike<TResult2>) | null,
): Promise<TResult1 | TResult2>
Type Parameters
- TResult1 = Result<T, E>
- TResult2 = never
Parameters
- Optionalonfulfilled: ((value: Result<T, E>) => TResult1 | PromiseLike<TResult1>) | null
- Optionalonrejected: ((reason: unknown) => TResult2 | PromiseLike<TResult2>) | null
Returns Promise<TResult1 | TResult2>
- Defined in src/result/result/asyncResult.ts:72

`Protected`transform

transform<R extends Result<OkContent<R>, ErrContent<R>>>(
fn: (r: Result<T, E>) => Promise<R>,
): AsyncResult<OkContent<R>, ErrContent<R>>
Type Parameters
- R extends Result<OkContent<R>, ErrContent<R>>
Parameters
- fn: (r: Result<T, E>) => Promise<R>
Returns AsyncResult<OkContent<R>, ErrContent<R>>
- Defined in src/result/result/asyncResult.ts:33

`Static`all

all<const T extends readonly PromiseLike<Result<unknown, unknown>>[]>(
results: T,
): AsyncResult<AsyncResultOkTypes<T>, AsyncResultErrTypes<T>[number]>
AsyncResult version of Promise.all with fail-fast semantics.
- Resolves to Ok([...]) once all inputs resolve to Ok (values preserved in input order).
- Resolves to Err(e) as soon as the first input (in time, not array order) resolves to Err, without waiting for the rest to settle.
- Rejects if any input's underlying Promise rejects.
Type Parameters
- const T extends readonly PromiseLike<Result<unknown, unknown>>[]
Parameters
- results: T
Returns AsyncResult<AsyncResultOkTypes<T>, AsyncResultErrTypes<T>[number]>
See
AsyncResult.merge for the variant that waits for every input before picking the first Err by array order.
Example
```
const slow = AsyncResult.from(
  new Promise(r => setTimeout(() => r(ok(1)), 1000)),
)
const fast = AsyncResult.from(err('boom'))
const result = await AsyncResult.all([slow, fast])
expect(result.unwrapErr()).toBe('boom') // resolves ~immediately
```
- Defined in src/result/result/asyncResult.ts:157

`Static`from

from<R extends Result<OkContent<R>, ErrContent<R>>>(
input: R | PromiseLike<R> | (() => R | PromiseLike<R>),
): AsyncResult<OkContent<R>, ErrContent<R>>
Create an AsyncResult from a Result, a PromiseLike, or a function returning a Result or a PromiseLike. Does not throw synchronously; rejections from the input promise propagate through the returned thenable.
Type Parameters
- R extends Result<OkContent<R>, ErrContent<R>>
Parameters
- input: R | PromiseLike<R> | (() => R | PromiseLike<R>)
  A Result, a PromiseLike, or a function returning a Result or a PromiseLike.
Returns AsyncResult<OkContent<R>, ErrContent<R>>
An AsyncResult.
- Defined in src/result/result/asyncResult.ts:23

`Static`merge

merge<const T extends readonly PromiseLike<Result<unknown, unknown>>[]>(
    results: T,
): AsyncResult<
    ResultOkTypes<
        { -readonly [P in string
        | number
        | symbol]: Awaited<T[P]> },
    >,
    ResultErrTypes<
        { -readonly [P in string
        | number
        | symbol]: Awaited<T[P]> },
    >[number],
>
Waits for every input to settle as a Result, then returns the first Err by array order (or Ok([...]) if none errored).

Unlike AsyncResult.all, an early Err does not short-circuit the wait. Underlying promise rejections still reject via Promise.all (rejections are not converted to Err values).
Type Parameters
- const T extends readonly PromiseLike<Result<unknown, unknown>>[]
Parameters
- results: T
  An array of AsyncResults to merge.
Returns AsyncResult<
    ResultOkTypes<
        { -readonly [P in string
        | number
        | symbol]: Awaited<T[P]> },
    >,
    ResultErrTypes<
        { -readonly [P in string
        | number
        | symbol]: Awaited<T[P]> },
    >[number],
>
An AsyncResult that is either an array of all Ok values or the first Err value (by array order).
See
AsyncResult.all for fail-fast-on-Err semantics.
Example
```
// ok
const asyncResult1 = AsyncResult.from(ok(1))
const asyncResult2 = AsyncResult.from(ok("2"))
const asyncResult3 = AsyncResult.from(ok(3n))
const merged = await AsyncResult.merge([asyncResult1, asyncResult2, asyncResult3])
expect(merged.unwrap()).toEqual([1, "2", 3n])
// err
const asyncResult1 = AsyncResult.from(ok(1))
const asyncResult2 = AsyncResult.from(err("2"))
const asyncResult3 = AsyncResult.from(err(3n))
const merged = await AsyncResult.merge([asyncResult1, asyncResult2, asyncResult3])
expect(merged.unwrapErr()).toBe("2")
```
- Defined in src/result/result/asyncResult.ts:131

Class AsyncResult<T, E>

Type Parameters

Index

Constructors

Properties

Methods

Constructors

constructor

Type Parameters

Parameters

Returns AsyncResult<T, E>

Properties

Protected Readonlypromise

Methods

[asyncIterator]

Returns AsyncGenerator<Err<E>, T>

and

Type Parameters

Parameters

Returns AsyncResult<OkContent<R2>, E | ErrContent<R2>>

andThen

Type Parameters

Parameters

Returns AsyncResult<OkContent<R2>, E | ErrContent<R2>>

inspect

Parameters

Returns AsyncResult<T, E>

inspectErr

Parameters

Returns AsyncResult<T, E>

map

Type Parameters

Parameters

Returns AsyncResult<T2, E>

mapErr

Type Parameters

Parameters

Returns AsyncResult<T, E2>

or

Type Parameters

Parameters

Returns AsyncResult<T | OkContent<R2>, ErrContent<R2>>

orElse

Type Parameters

Parameters

Returns AsyncResult<T | OkContent<R2>, ErrContent<R2>>

then

Type Parameters

Parameters

Returns Promise<TResult1 | TResult2>

Protectedtransform

Type Parameters

Parameters

Returns AsyncResult<OkContent<R>, ErrContent<R>>

Staticall

Type Parameters

Parameters

Returns AsyncResult<AsyncResultOkTypes<T>, AsyncResultErrTypes<T>[number]>

See

Example

Staticfrom

Type Parameters

Parameters

Returns AsyncResult<OkContent<R>, ErrContent<R>>

Staticmerge

Type Parameters

Parameters

Returns AsyncResult< ResultOkTypes< { -readonly [P in string | number | symbol]: Awaited<T[P]> }, >, ResultErrTypes< { -readonly [P in string | number | symbol]: Awaited<T[P]> }, >[number],>

See

Example

Settings

On This Page

`Protected` `Readonly`promise

`Protected`transform

`Static`all

`Static`from

`Static`merge

Returns AsyncResult<
ResultOkTypes<
{ -readonly [P in string
| number
| symbol]: Awaited<T[P]> },
>,
ResultErrTypes<
{ -readonly [P in string
| number
| symbol]: Awaited<T[P]> },
>[number],
>