@xylabs/promise

Base functionality used throughout XY Labs TypeScript/JavaScript libraries

Reference

@xylabs/promise

Classes

• PromiseEx

Interfaces

• PromiseType

Type Aliases

• PromiseExSubFunc
• PromiseExFunc
• PromiseExValueFunc
• AnyNonPromise
• Promisable
• PromisableArray
• OptionalPromisable
• OptionalPromisableArray
• NullablePromisable
• NullablePromisableArray
• AsyncMutex

Functions

• fulfilled
• fulfilledValues
• isPromise
• rejected
• toPromise

classes

PromiseEx

@xylabs/promise

Extends

• Promise<T>

Type Parameters

T

T

V

V = void

Constructors

Constructor

new PromiseEx<T, V>(func, value?): PromiseEx<T, V>;

Parameters

func

PromiseExFunc<T>

value?

V

Returns

PromiseEx<T, V>

Overrides

Promise<T>.constructor

Properties

cancelled?

optional cancelled: boolean;

Methods

then()

then<TResult1, TResult2>(
   onfulfilled?, 
   onrejected?, 
onvalue?): Promise<TResult1 | TResult2>;

Attaches callbacks for the resolution and/or rejection of the Promise.

Type Parameters

TResult1

TResult1 = T

TResult2

TResult2 = never

Parameters

onfulfilled?

The callback to execute when the Promise is resolved.

null | (value) => TResult1 | PromiseLike<TResult1>

onrejected?

The callback to execute when the Promise is rejected.

null | (reason) => TResult2 | PromiseLike<TResult2>

onvalue?

(value?) => boolean

Returns

Promise<TResult1 | TResult2>

A Promise for the completion of which ever callback is executed.

Overrides

Promise.then

value()

value(onvalue?): PromiseEx<T, V>;

Parameters

onvalue?

(value?) => boolean

Returns

PromiseEx<T, V>

functions

fulfilled

@xylabs/promise

function fulfilled<T>(val): val is PromiseFulfilledResult<T>;

For use with Promise.allSettled to filter only successful results

Type Parameters

T

T

Parameters

val

PromiseSettledResult<T>

Returns

val is PromiseFulfilledResult<T>

fulfilledValues

@xylabs/promise

function fulfilledValues<T>(previousValue, currentValue): T[];

For use with Promise.allSettled to reduce to only successful result values

Type Parameters

T

T

Parameters

previousValue

T[]

currentValue

PromiseSettledResult<T>

Returns

T[]

Examples

const resolved = Promise.resolve('resolved')
const rejected = Promise.reject('rejected')
const settled = await Promise.allSettled([resolved, rejected])
const results = settled.reduce(fulfilledValues, [] as string[])
// results === [ 'resolved' ]

const resolved = Promise.resolve('resolved')
const rejected = Promise.reject('rejected')
const settled = await Promise.allSettled([resolved, rejected])
const results = settled.reduce<string[]>(fulfilledValues, [])
// results === [ 'resolved' ]

isPromise

@xylabs/promise

function isPromise(value): value is Promise<unknown>;

Parameters

value

unknown

Returns

value is Promise<unknown>

rejected

@xylabs/promise

function rejected<T>(val): val is PromiseRejectedResult;

For use with Promise.allSettled to filter only rejected results

Type Parameters

T

T

Parameters

val

PromiseSettledResult<T>

Returns

val is PromiseRejectedResult

toPromise

@xylabs/promise

function toPromise<T>(value): Promise<T>;

Type Parameters

T

T

Parameters

value

Promisable<T>

Returns

Promise<T>

interfaces

PromiseType

@xylabs/promise

Properties

then()

then: () => unknown;

Returns

unknown

type-aliases

AnyNonPromise

@xylabs/promise

type AnyNonPromise = Exclude<TypedValue, PromiseType>;

AsyncMutex

@xylabs/promise

type AsyncMutex<T> = Promise<T>;

Type Parameters

T

T

Description

Used to document promises that are being used as Mutexes

NullablePromisable

@xylabs/promise

type NullablePromisable<T, V> = Promisable<T | null, V>;

Type Parameters

T

T

V

V = never

NullablePromisableArray

@xylabs/promise

type NullablePromisableArray<T, V> = PromisableArray<T | null, V>;

Type Parameters

T

T

V

V = never

OptionalPromisable

@xylabs/promise

type OptionalPromisable<T, V> = Promisable<T | undefined, V>;

Type Parameters

T

T

V

V = never

OptionalPromisableArray

@xylabs/promise

type OptionalPromisableArray<T, V> = PromisableArray<T | undefined, V>;

Type Parameters

T

T

V

V = never

Promisable

@xylabs/promise

type Promisable<T, V> = PromiseEx<T, V> | Promise<T> | T;

Type Parameters

T

T

V

V = never

PromisableArray

@xylabs/promise

type PromisableArray<T, V> = Promisable<T[], V>;

Type Parameters

T

T

V

V = never

PromiseExFunc

@xylabs/promise

type PromiseExFunc<T> = (resolve?, reject?) => void;

Type Parameters

T

T

Parameters

resolve?

PromiseExSubFunc<T, void>

reject?

PromiseExSubFunc<T, void>

Returns

void

PromiseExSubFunc

@xylabs/promise

type PromiseExSubFunc<T, TResult> = (value) => TResult;

Type Parameters

T

T

TResult

TResult = T

Parameters

value

T

Returns

TResult

PromiseExValueFunc

@xylabs/promise

type PromiseExValueFunc<V> = (value?) => boolean;

Type Parameters

V

V

Parameters

value?

V

Returns

boolean

Part of sdk-js

Maintainers

• Arie Trouw (arietrouw.com)
• Matt Jones
• Joel Carter
• Jordan Trouw

License

See the LICENSE file for license details

Credits

Made with 🔥 and ❄️ by XYLabs