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fp-ts-remote-data

index overview 

type RemoteData<E, A> = Pending | Failure<E> | Success<A>

Represents and async value of one of two possible types (a disjoint union). Value can also be empty with Pending value.

An instance of RemoteData is either an instance of Pending, Failure or Success.

A common use of RemoteData is as an alternative to Either for dealing with possible missing values on pending.

Added in v2.0.0

Table of contents

Alt

alt

Signature

export declare const alt: <E, A>(that: Lazy<RemoteData<E, A>>) => (fa: RemoteData<E, A>) => RemoteData<E, A>

Added in v2.0.0

altW

Signature

export declare const altW: <E2, B>(
  that: Lazy<RemoteData<E2, B>>
) => <E1, A>(fa: RemoteData<E1, A>) => RemoteData<E2 | E1, B | A>

Added in v2.0.0

Applicative

of

Wrap a value into the type constructor.

Signature

export declare const of: <E, A>(a: A) => RemoteData<E, A>

Added in v2.0.0

Apply

ap

Signature

export declare const ap: <E, A>(fa: RemoteData<E, A>) => <B>(fab: RemoteData<E, (a: A) => B>) => RemoteData<E, B>

Added in v2.0.0

apW

Signature

export declare const apW: <D, A>(
  fa: RemoteData<D, A>
) => <E, B>(fab: RemoteData<E, (a: A) => B>) => RemoteData<D | E, B>

Added in v2.0.0

Bifunctor

bimap

Signature

export declare const bimap: <E, G, A, B>(f: (e: E) => G, g: (a: A) => B) => (fa: RemoteData<E, A>) => RemoteData<G, B>

Added in v2.0.0

mapLeft

Signature

export declare const mapLeft: <E, G>(f: (e: E) => G) => <A>(fa: RemoteData<E, A>) => RemoteData<G, A>

Added in v2.0.0

Extend

extend

Signature

export declare const extend: <E, A, B>(f: (wa: RemoteData<E, A>) => B) => (wa: RemoteData<E, A>) => RemoteData<E, B>

Added in v2.0.0

Foldable

foldMap

Signature

export declare const foldMap: <M>(M: Monoid<M>) => <A>(f: (a: A) => M) => <E>(fa: RemoteData<E, A>) => M

Added in v2.0.0

reduce

Signature

export declare const reduce: <A, B>(b: B, f: (b: B, a: A) => B) => <E>(fa: RemoteData<E, A>) => B

Added in v2.0.0

reduceRight

Signature

export declare const reduceRight: <A, B>(b: B, f: (a: A, b: B) => B) => <E>(fa: RemoteData<E, A>) => B

Added in v2.0.0

Functor

map

Signature

export declare const map: <A, B>(f: (a: A) => B) => <E>(fa: RemoteData<E, A>) => RemoteData<E, B>

Added in v2.0.0

Monad

chain

Signature

export declare const chain: <E, A, B>(f: (a: A) => RemoteData<E, B>) => (ma: RemoteData<E, A>) => RemoteData<E, B>

Added in v2.0.0

chainW

Signature

export declare const chainW: <D, A, B>(
  f: (a: A) => RemoteData<D, B>
) => <E>(ma: RemoteData<E, A>) => RemoteData<D | E, B>

Added in v2.0.0

MonadThrow

throwError

Signature

export declare const throwError: <E, A>(e: E) => RemoteData<E, A>

Added in v2.0.0

Traversable

sequence

Signature

export declare const sequence: Sequence2<'RemoteData'>

Added in v2.0.0

traverse

Signature

export declare const traverse: PipeableTraverse2<'RemoteData'>

Added in v2.0.0

combinators

apFirst

Combine two effectful actions, keeping only the result of the first.

Derivable from Apply.

Signature

export declare const apFirst: <E, B>(fb: RemoteData<E, B>) => <A>(fa: RemoteData<E, A>) => RemoteData<E, A>

Added in v2.0.0

apSecond

Combine two effectful actions, keeping only the result of the second.

Derivable from Apply.

Signature

export declare const apSecond: <E, B>(fb: RemoteData<E, B>) => <A>(fa: RemoteData<E, A>) => RemoteData<E, B>

Added in v2.0.0

chainEither

Signature

export declare const chainEither: <E, A, B>(f: (a: A) => Either<E, B>) => (ma: RemoteData<E, A>) => RemoteData<E, B>

Added in v2.0.0

chainEitherW

Signature

export declare const chainEitherW: <D, A, B>(
  f: (a: A) => Either<D, B>
) => <E>(ma: RemoteData<E, A>) => RemoteData<D | E, B>

Added in v2.0.0

chainFirst

Composes computations in sequence, using the return value of one computation to determine the next computation and keeping only the result of the first.

Derivable from Monad.

Signature

export declare const chainFirst: <E, A, B>(f: (a: A) => RemoteData<E, B>) => (ma: RemoteData<E, A>) => RemoteData<E, A>

Added in v2.0.0

chainFirstW

Less strict version of chainFirst

Signature

export declare const chainFirstW: <D, A, B>(
  f: (a: A) => RemoteData<D, B>
) => <E>(ma: RemoteData<E, A>) => RemoteData<D | E, A>

Added in v2.0.0

chainNullableK

Signature

export declare function chainNullableK<E>(
  e: Lazy<E>
): <A, B>(f: (a: A) => B | null | undefined) => (ma: RemoteData<E, A>) => RemoteData<E, NonNullable<B>>

Added in v2.0.0

duplicate

Derivable from Extend.

Signature

export declare const duplicate: <E, A>(ma: RemoteData<E, A>) => RemoteData<E, RemoteData<E, A>>

Added in v2.0.0

filterOrElse

Signature

export declare const filterOrElse: {
  <E, A, B extends A>(refinement: Refinement<A, B>, onFalse: (a: A) => E): (ma: RemoteData<E, A>) => RemoteData<E, B>
  <E, A>(predicate: Predicate<A>, onFalse: (a: A) => E): (ma: RemoteData<E, A>) => RemoteData<E, A>
}

Added in v2.0.0

filterOrElseW

Signature

export declare const filterOrElseW: {
  <A, B extends A, E2>(refinement: Refinement<A, B>, onFalse: (a: A) => E2): <E1>(
    ma: RemoteData<E1, A>
  ) => RemoteData<E2 | E1, B>
  <A, E2>(predicate: Predicate<A>, onFalse: (a: A) => E2): <E1>(ma: RemoteData<E1, A>) => RemoteData<E2 | E1, A>
}

Added in v2.0.0

flatten

Signature

export declare const flatten: <E, A>(mma: RemoteData<E, RemoteData<E, A>>) => RemoteData<E, A>

Added in v2.0.0

fromNullableK

Signature

export declare function fromNullableK<E>(
  e: Lazy<E>
): <A extends ReadonlyArray<unknown>, B>(
  f: (...a: A) => B | null | undefined
) => (...a: A) => RemoteData<E, NonNullable<B>>

Added in v2.0.0

orElse

Signature

export declare const orElse: <E, A, M>(
  onFailure: (e: E) => RemoteData<M, A>
) => (ma: RemoteData<E, A>) => RemoteData<M, A>

Added in v2.0.0

orElseW

Signature

export declare const orElseW: <E, A, M, B>(
  onFailure: (e: E) => RemoteData<M, B>
) => (ma: RemoteData<E, A>) => RemoteData<M, A | B>

Added in v2.0.0

swap

Signature

export declare function swap<E, A>(ma: RemoteData<E, A>): RemoteData<A, E>

Added in v2.0.0

constructors

failure

Constructs a new RemoteData holding an Failure value.

Signature

export declare const failure: <E = never, A = never>(e: E) => RemoteData<E, A>

Added in v2.0.0

fromEither

Takes an Either and return a Success if Right, Failure if Left

Signature

export declare function fromEither<E, A>(ei: Either<E, A>): RemoteData<E, A>

Added in v2.0.0

fromNullable

Takes a default and a nullable value, if the value is not nully, turn it into a Success, if the value is nully use the provided default as a Failure.

Signature

export declare function fromNullable<E>(onNull: Lazy<E>): <A>(a: A) => RemoteData<E, NonNullable<A>>

Added in v2.0.0

fromOption

Takes an Option and return a Success if Some, Failure if None with onNone function

Signature

export declare function fromOption<E>(onNone: Lazy<E>): <A>(ma: Option<A>) => RemoteData<E, A>

Added in v2.0.0

fromPredicate

Signature

export declare const fromPredicate: {
  <E, A, B extends A>(refinement: Refinement<A, B>, onFalse: (a: A) => E): (a: A) => RemoteData<E, B>
  <E, A>(predicate: Predicate<A>, onFalse: (a: A) => E): (a: A) => RemoteData<E, A>
}

Added in v2.0.0

pending

Get a RemoteData with a pending state

Signature

export declare const pending: RemoteData<never, never>

Added in v2.0.0

success

Constructs a new RemoteData holding a Success value.

Signature

export declare const success: <E = never, A = never>(a: A) => RemoteData<E, A>

Added in v2.0.0

destructors

fold

Signature

export declare function fold<E, A, B>(
  onPending: () => B,
  onSuccess: (a: A) => B,
  onFailure: (e: E) => B
): (ma: RemoteData<E, A>) => B

Added in v2.0.0

getFailure

Signature

export declare function getFailure<E, A>(ma: RemoteData<E, A>): Option<E>

Added in v2.0.0

getSuccess

Signature

export declare function getSuccess<E, A>(ma: RemoteData<E, A>): Option<A>

Added in v2.0.0

toEither

Signature

export declare function toEither<E>(onPending: () => E): <A>(ma: RemoteData<E, A>) => Either<E, A>

Added in v2.0.0

toNullable

Signature

export declare function toNullable<E, A>(ma: RemoteData<E, A>): A | null

Added in v2.0.0

toUndefined

Signature

export declare function toUndefined<E, A>(ma: RemoteData<E, A>): A | undefined

Added in v2.0.0

guards

isFailure

Returns true if the RemoteData is an instance of Failure, false otherwise.

Signature

export declare const isFailure: <E, A>(ma: RemoteData<E, A>) => ma is Failure<E>

Example

import * as RD from 'fp-ts-remote-data'

RD.isSuccess(RD.success(1)) // false
RD.isSuccess(RD.failure(1)) // true
RD.isSuccess(RD.pending) // false

Added in v2.0.0

isPending

Returns true if the RemoteData is an instance of Pending, false otherwise.

Signature

export declare const isPending: <E, A>(ma: RemoteData<E, A>) => ma is Pending

Example

import * as RD from 'fp-ts-remote-data'

RD.isPending(RD.success(1)) // false
RD.isPending(RD.failure(1)) // false
RD.isPending(RD.pending) // true

Added in v2.0.0

isSuccess

Returns true if the RemoteData is an instance of Success, false otherwise.

Signature

export declare const isSuccess: <E, A>(ma: RemoteData<E, A>) => ma is Success<A>

Example

import * as RD from 'fp-ts-remote-data'

RD.isSuccess(RD.success(1)) // true
RD.isSuccess(RD.failure(1)) // false
RD.isSuccess(RD.pending) // false

Added in v2.0.0

instances

Alt

Signature

export declare const Alt: Alt2<'RemoteData'>

Added in v2.0.0

Applicative

Signature

export declare const Applicative: Applicative2<'RemoteData'>

Added in v2.0.0

Bifunctor

Signature

export declare const Bifunctor: Bifunctor2<'RemoteData'>

Added in v2.0.0

Extend

Signature

export declare const Extend: Extend2<'RemoteData'>

Added in v2.0.0

Foldable

Signature

export declare const Foldable: Foldable2<'RemoteData'>

Added in v2.0.0

Functor

Signature

export declare const Functor: Functor2<'RemoteData'>

Added in v2.0.0

Monad

Signature

export declare const Monad: Monad2<'RemoteData'>

Added in v2.0.0

MonadThrow

Signature

export declare const MonadThrow: MonadThrow2<'RemoteData'>

Added in v2.0.0

Traversable

Signature

export declare const Traversable: Traversable2<'RemoteData'>

Added in v2.0.0

URI

Signature

export declare const URI: 'RemoteData'

Added in v2.0.0

URI (type alias)

Signature

export type URI = typeof URI

Added in v2.0.0

remoteData

Signature

export declare const remoteData: Monad2<'RemoteData'> &
  Foldable2<'RemoteData'> &
  Traversable2<'RemoteData'> &
  Bifunctor2<'RemoteData'> &
  Alt2<'RemoteData'> &
  Extend2<'RemoteData'> &
  MonadThrow2<'RemoteData'>

Added in v2.0.0

model

Failure (interface)

Signature

export interface Failure<E> {
  readonly _tag: 'Failure'
  readonly failure: E
}

Added in v2.0.0

Pending (interface)

Signature

export interface Pending {
  readonly _tag: 'Pending'
}

Added in v2.0.0

RemoteData (type alias)

Signature

export type RemoteData<E, A> = Pending | Success<A> | Failure<E>

Added in v2.0.0

Success (interface)

Signature

export interface Success<A> {
  readonly _tag: 'Success'
  readonly success: A
}

Added in v2.0.0

utils

elem

Signature

export declare function elem<A>(
  E: Eq<A>
): {
  (a: A): <E>(ma: RemoteData<E, A>) => boolean
  <E>(a: A, ma: RemoteData<E, A>): boolean
}

Added in v2.0.0

exists

Signature

export declare function exists<A>(predicate: Predicate<A>): <E>(ma: RemoteData<E, A>) => boolean

Added in v2.0.0