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ReaderTaskEither

Instances​

Combinators​

Constructors​

Conversions​

Do notation​

Error handling​

Filtering​

Instance methods​

Legacy​

Lifting​

Mapping​

Model​

Pattern matching​

Sequencing​

Traversing​

Type lambdas​

Utilities​

Instances​

Alt​

Signature​

export declare const Alt: Alt3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

ApplicativePar​

Runs computations in parallel.

Signature​

export declare const ApplicativePar: Applicative3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

ApplicativeSeq​

Runs computations sequentially.

Signature​

export declare const ApplicativeSeq: Applicative3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

ApplyPar​

Runs computations in parallel.

Signature​

export declare const ApplyPar: Apply3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

ApplySeq​

Runs computations sequentially.

Signature​

export declare const ApplySeq: Apply3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Bifunctor​

Signature​

export declare const Bifunctor: Bifunctor3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Chain​

Signature​

export declare const Chain: chainable.Chain3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

ChainRec​

ChainRec for ReaderTaskEither

Signature​

export declare const ChainRec: ChainRec3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2022-present Jacob Alford

FromEither​

Signature​

export declare const FromEither: FromEither3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

FromIO​

Signature​

export declare const FromIO: FromIO3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

FromReader​

Signature​

export declare const FromReader: FromReader3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

FromTask​

Signature​

export declare const FromTask: FromTask3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Functor​

Signature​

export declare const Functor: Functor3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Monad​

Signature​

export declare const Monad: Monad3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

MonadIO​

Signature​

export declare const MonadIO: MonadIO3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

MonadTask​

Signature​

export declare const MonadTask: MonadTask3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

MonadThrow​

Signature​

export declare const MonadThrow: MonadThrow3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Pointed​

Signature​

export declare const Pointed: Pointed3<URI>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getReaderTaskValidation​

Use getApplicativeReaderTaskValidation and getAltReaderTaskValidation instead.

Signature​

export declare function getReaderTaskValidation<E>(
  SE: Semigroup<E>,
): Monad3C<URI, E> & Bifunctor3<URI> & Alt3C<URI, E> & MonadTask3C<URI, E> & MonadThrow3C<URI, E>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Combinators​

tap​

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

Signature​

export declare const tap: {
  <R1, E1, A, R2, E2, _>(
    self: ReaderTaskEither<R1, E1, A>,
    f: (a: A) => ReaderTaskEither<R2, E2, _>,
  ): ReaderTaskEither<R1 & R2, E1 | E2, A>
  <A, R2, E2, _>(
    f: (a: A) => ReaderTaskEither<R2, E2, _>,
  ): <R1, E1>(self: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E2 | E1, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapEither​

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

Signature​

export declare const tapEither: {
  <A, E2, _>(f: (a: A) => Either<E2, _>): <R, E1>(self: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, A>
  <R, E1, A, E2, _>(self: ReaderTaskEither<R, E1, A>, f: (a: A) => Either<E2, _>): ReaderTaskEither<R, E1 | E2, A>
}

Details​

  • Added in 0.1.0

Example​

import * as E from '@fp-tx/core/Either'
import { pipe } from '@fp-tx/core/function'
import * as RTE from '@fp-tx/core/ReaderTaskEither'

const checkString = (value: string) =>
  pipe(
    RTE.ask<number>(),
    RTE.tapEither(minLength => (value.length > minLength ? E.right('ok') : E.left('error'))),
  )

async function test() {
  assert.deepStrictEqual(await checkString('')(2)(), E.left('error'))
  assert.deepStrictEqual(await checkString('fp-ts')(2)(), E.right(2))
}

test()

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapIO​

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

Signature​

export declare const tapIO: {
  <A, _>(f: (a: A) => IO<_>): <R, E>(self: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>
  <R, E, A, _>(self: ReaderTaskEither<R, E, A>, f: (a: A) => IO<_>): ReaderTaskEither<R, E, A>
}

Details​

  • Added in 0.1.0

Example​

import * as RTE from '@fp-tx/core/ReaderTaskEither'
import * as E from '@fp-tx/core/Either'
import * as Console from '@fp-tx/core/Console'

// Will produce `Hello, fp-ts` to the stdout
const effect = RTE.tapIO(RTE.ask<string>(), value => Console.log(`Hello, ${value}`))

async function test() {
  assert.deepStrictEqual(await effect('fp-ts')(), E.of('fp-ts'))
}

test()

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapReader​

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

Signature​

export declare const tapReader: {
  <A, R2, _>(f: (a: A) => Reader<R2, _>): <R1, E>(self: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, A>
  <R1, E, A, R2, _>(self: ReaderTaskEither<R1, E, A>, f: (a: A) => Reader<R2, _>): ReaderTaskEither<R1 & R2, E, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapReaderEither​

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

Signature​

export declare const tapReaderEither: {
  <A, R2, E2, _>(
    f: (a: A) => ReaderEither<R2, E2, _>,
  ): <R1, E1>(self: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, A>
  <R1, E1, A, R2, E2, _>(
    self: ReaderTaskEither<R1, E1, A>,
    f: (a: A) => ReaderEither<R2, E2, _>,
  ): ReaderTaskEither<R1 & R2, E1 | E2, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapReaderIO​

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

Signature​

export declare const tapReaderIO: {
  <A, R2, _>(f: (a: A) => ReaderIO<R2, _>): <R1, E>(self: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, A>
  <R1, E, A, R2, _>(self: ReaderTaskEither<R1, E, A>, f: (a: A) => ReaderIO<R2, _>): ReaderTaskEither<R1 & R2, E, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapReaderTask​

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

Signature​

export declare const tapReaderTask: {
  <A, R2, _>(
    f: (a: A) => ReaderTask<R2, _>,
  ): <R1, E>(self: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, A>
  <R1, E, A, R2, _>(self: ReaderTaskEither<R1, E, A>, f: (a: A) => ReaderTask<R2, _>): ReaderTaskEither<R1 & R2, E, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapTask​

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

Signature​

export declare const tapTask: {
  <A, _>(f: (a: A) => Task<_>): <R, E>(self: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>
  <R, E, A, _>(self: ReaderTaskEither<R, E, A>, f: (a: A) => Task<_>): ReaderTaskEither<R, E, A>
}

Details​

  • Added in 0.1.0

Example​

import * as RTE from '@fp-tx/core/ReaderTaskEither'
import * as E from '@fp-tx/core/Either'
import * as T from '@fp-tx/core/Task'

const effect = RTE.tapTask(RTE.ask<number>(), value => T.of(value + 1))

async function test() {
  assert.deepStrictEqual(await effect(1)(), E.of(1))
}

test()

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapTaskEither​

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

Signature​

export declare const tapTaskEither: {
  <A, E2, _>(
    f: (a: A) => TaskEither<E2, _>,
  ): <R, E1>(self: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, A>
  <R, E1, A, E2, _>(self: ReaderTaskEither<R, E1, A>, f: (a: A) => TaskEither<E2, _>): ReaderTaskEither<R, E1 | E2, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Constructors​

ask​

Reads the current context.

Signature​

export declare const ask: <R, E = never>() => ReaderTaskEither<R, E, R>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

asks​

Projects a value from the global context in a ReaderEither.

Signature​

export declare const asks: <R, A, E = never>(f: (r: R) => A) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

asksReaderTaskEither​

Effectfully accesses the environment.

Signature​

export declare const asksReaderTaskEither: <R, E, A>(
  f: (r: R) => ReaderTaskEither<R, E, A>,
) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

asksReaderTaskEitherW​

Less strict version of asksReaderTaskEither.

The W suffix (short for Widening) means that the environment types will be merged.

Signature​

export declare const asksReaderTaskEitherW: <R1, R2, E, A>(
  f: (r1: R1) => ReaderTaskEither<R2, E, A>,
) => ReaderTaskEither<R1 & R2, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

left​

Signature​

export declare const left: <R, E = never, A = never>(e: E) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

leftIO​

Signature​

export declare const leftIO: <R, E = never, A = never>(me: IO<E>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

leftReader​

Signature​

export declare const leftReader: <R, E = never, A = never>(me: Reader<R, E>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

leftReaderIO​

Signature​

export declare const leftReaderIO: <R, E = never, A = never>(me: ReaderIO<R, E>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

leftReaderTask​

Signature​

export declare const leftReaderTask: <R, E = never, A = never>(me: ReaderTask<R, E>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

leftTask​

Signature​

export declare const leftTask: <R, E = never, A = never>(me: Task<E>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

of​

Signature​

export declare const of: <R = unknown, E = never, A = never>(a: A) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Signature​

export declare const right: <R, E = never, A = never>(a: A) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

rightIO​

Signature​

export declare const rightIO: <R, E = never, A = never>(ma: IO<A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

rightReader​

Signature​

export declare const rightReader: <R, E = never, A = never>(ma: Reader<R, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

rightReaderIO​

Signature​

export declare const rightReaderIO: <R, E = never, A = never>(ma: ReaderIO<R, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

rightReaderTask​

Signature​

export declare const rightReaderTask: <R, E = never, A = never>(ma: ReaderTask<R, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

rightTask​

Signature​

export declare const rightTask: <R, E = never, A = never>(ma: Task<A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Conversions​

fromEither​

Signature​

export declare const fromEither: <E, A, R = unknown>(fa: Either<E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromIO​

Signature​

export declare const fromIO: <A, R = unknown, E = never>(fa: IO<A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromIOEither​

Signature​

export declare const fromIOEither: <E, A, R = unknown>(fa: IOEither<E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromNullable​

Signature​

export declare const fromNullable: <E>(e: E) => <R, A>(a: A) => ReaderTaskEither<R, E, NonNullable<A>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromOption​

Signature​

export declare const fromOption: <E>(onNone: LazyArg<E>) => <A, R = unknown>(fa: Option<A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromReader​

Signature​

export declare const fromReader: <R, A, E = never>(fa: Reader<R, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromReaderEither​

Signature​

export declare const fromReaderEither: <R, E, A>(fa: ReaderEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromTask​

Signature​

export declare const fromTask: <A, R = unknown, E = never>(fa: Task<A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromTaskEither​

Signature​

export declare const fromTaskEither: <E, A, R = unknown>(fa: TaskEither<E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

toUnion​

Signature​

export declare const toUnion: <R, E, A>(fa: ReaderTaskEither<R, E, A>) => ReaderTask<R, E | A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Do notation​

Do​

Signature​

export declare const Do: ReaderTaskEither<unknown, never, {}>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

apS​

Signature​

export declare const apS: <N extends string, A, R, E, B>(
  name: Exclude<N, keyof A>,
  fb: ReaderTaskEither<R, E, B>,
) => (
  fa: ReaderTaskEither<R, E, A>,
) => ReaderTaskEither<R, E, { readonly [K in N | keyof A]: K extends keyof A ? A[K] : B }>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

apSW​

Less strict version of apS.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const apSW: <A, N extends string, R2, E2, B>(
  name: Exclude<N, keyof A>,
  fb: ReaderTaskEither<R2, E2, B>,
) => <R1, E1>(
  fa: ReaderTaskEither<R1, E1, A>,
) => ReaderTaskEither<
  R1 & R2,
  E1 | E2,
  {
    readonly [K in keyof A | N]: K extends keyof A ? A[K] : B
  }
>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

bind​

Signature​

export declare const bind: <N extends string, A, R, E, B>(
  name: Exclude<N, keyof A>,
  f: (a: A) => ReaderTaskEither<R, E, B>,
) => (
  ma: ReaderTaskEither<R, E, A>,
) => ReaderTaskEither<R, E, { readonly [K in N | keyof A]: K extends keyof A ? A[K] : B }>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

bindTo​

Signature​

export declare const bindTo: <N extends string>(
  name: N,
) => <R, E, A>(fa: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, { readonly [K in N]: A }>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

bindW​

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const bindW: <N extends string, A, R2, E2, B>(
  name: Exclude<N, keyof A>,
  f: (a: A) => ReaderTaskEither<R2, E2, B>,
) => <R1, E1>(
  fa: ReaderTaskEither<R1, E1, A>,
) => ReaderTaskEither<
  R1 & R2,
  E1 | E2,
  {
    readonly [K in keyof A | N]: K extends keyof A ? A[K] : B
  }
>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Error handling​

alt​

Identifies an associative operation on a type constructor. It is similar to Semigroup, except that it applies to types of kind * -> *.

Signature​

export declare const alt: <R, E, A>(
  that: () => ReaderTaskEither<R, E, A>,
) => (fa: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

altW​

Less strict version of alt.

The W suffix (short for Widening) means that the environment, the error and the return types will be merged.

Signature​

export declare const altW: <R2, E2, B>(
  that: () => ReaderTaskEither<R2, E2, B>,
) => <R1, E1, A>(fa: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E2, A | B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getAltReaderTaskValidation​

The default Alt instance returns the last error, if you want to get all errors you need to provide a way to concatenate them via a Semigroup.

See getAltValidation.

Signature​

export declare function getAltReaderTaskValidation<E>(S: Semigroup<E>): Alt3C<URI, E>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getApplicativeReaderTaskValidation​

The default ApplicativePar instance returns the first error, if you want to get all errors you need to provide a way to concatenate them via a Semigroup.

See getApplicativeValidation.

Signature​

export declare function getApplicativeReaderTaskValidation<E>(A: Apply1<T.URI>, S: Semigroup<E>): Applicative3C<URI, E>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getOrElse​

Signature​

export declare const getOrElse: <R, E, A>(
  onLeft: (e: E) => ReaderTask<R, A>,
) => (ma: ReaderTaskEither<R, E, A>) => ReaderTask<R, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getOrElseW​

Less strict version of getOrElse.

The W suffix (short for Widening) means that the handler return type will be merged.

Signature​

export declare const getOrElseW: <R2, E, B>(
  onLeft: (e: E) => ReaderTask<R2, B>,
) => <R1, A>(ma: ReaderTaskEither<R1, E, A>) => ReaderTask<R1 & R2, A | B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

mapBoth​

Returns a ReaderTaskEither whose failure and success channels have been mapped by the specified pair of functions, f and g.

Signature​

export declare const mapBoth: {
  <E, G, A, B>(f: (e: E) => G, g: (a: A) => B): <R>(self: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, G, B>
  <R, E, A, G, B>(self: ReaderTaskEither<R, E, A>, f: (e: E) => G, g: (a: A) => B): ReaderTaskEither<R, G, B>
}

Details​

  • Added in 0.1.0

Example​

import * as ReaderTaskEither from '@fp-tx/core/ReaderTaskEither'
import * as Either from '@fp-tx/core/Either'

const f = (s: string) => new Error(s)
const g = (n: number) => n * 2

async function test() {
  assert.deepStrictEqual(await ReaderTaskEither.mapBoth(ReaderTaskEither.right(1), f, g)({})(), Either.right(2))
  assert.deepStrictEqual(
    await ReaderTaskEither.mapBoth(ReaderTaskEither.left('err'), f, g)({})(),
    Either.left(new Error('err')),
  )
}

test()

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

mapError​

Returns a ReaderTaskEither with its error channel mapped using the specified function.

Signature​

export declare const mapError: {
  <R, E, G>(f: (e: E) => G): <A>(self: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, G, A>
  <R, E, A, G>(self: ReaderTaskEither<R, E, A>, f: (e: E) => G): ReaderTaskEither<R, G, A>
}

Details​

  • Added in 0.1.0

Example​

import * as ReaderTaskEither from '@fp-tx/core/ReaderTaskEither'
import * as Either from '@fp-tx/core/Either'

const f = (s: string) => new Error(s)

async function test() {
  assert.deepStrictEqual(await ReaderTaskEither.mapError(ReaderTaskEither.right(1), f)({})(), Either.right(1))
  assert.deepStrictEqual(
    await ReaderTaskEither.mapError(ReaderTaskEither.left('err'), f)({})(),
    Either.left(new Error('err')),
  )
}

test()

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

orElse​

Signature​

export declare const orElse: <R, E1, A, E2>(
  onLeft: (e: E1) => ReaderTaskEither<R, E2, A>,
) => (ma: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

orElseW​

Less strict version of orElse.

The W suffix (short for Widening) means that the environment types and the return types will be merged.

Signature​

export declare const orElseW: <E1, R1, E2, B>(
  onLeft: (e: E1) => ReaderTaskEither<R1, E2, B>,
) => <R2, A>(ma: ReaderTaskEither<R2, E1, A>) => ReaderTaskEither<R1 & R2, E2, A | B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

orLeft​

Signature​

export declare const orLeft: <E1, R, E2>(
  onLeft: (e: E1) => ReaderTask<R, E2>,
) => <A>(fa: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tapError​

Returns an effect that effectfully "peeks" at the failure of this effect.

Signature​

export declare const tapError: {
  <E1, R2, E2, _>(
    onLeft: (e: E1) => ReaderTaskEither<R2, E2, _>,
  ): <R1, A>(self: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, A>
  <R1, E1, A, R2, E2, _>(
    self: ReaderTaskEither<R1, E1, A>,
    onLeft: (e: E1) => ReaderTaskEither<R2, E2, _>,
  ): ReaderTaskEither<R1 & R2, E1 | E2, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Filtering​

filterOrElse​

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

filterOrElseW​

Less strict version of filterOrElse.

The W suffix (short for Widening) means that the error types will be merged.

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getCompactable​

Signature​

export declare const getCompactable: <E>(M: Monoid<E>) => Compactable3C<'ReaderTaskEither', E>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getFilterable​

Signature​

export declare function getFilterable<E>(M: Monoid<E>): Filterable3C<URI, E>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Instance methods​

chainRec​

Signature​

export declare const chainRec: ChainRec3<URI>['chainRec']

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2022-present Jacob Alford

Legacy​

bimap​

Alias of mapBoth.

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chain​

Alias of flatMap.

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainEitherK​

Alias of flatMapEither.

Signature​

export declare const chainEitherK: <E, A, B>(
  f: (a: A) => E.Either<E, B>,
) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainEitherKW​

Alias of flatMapEither.

Signature​

export declare const chainEitherKW: <E2, A, B>(
  f: (a: A) => Either<E2, B>,
) => <R, E1>(ma: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirst​

Alias of tap.

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstEitherK​

Alias of tapEither.

Signature​

export declare const chainFirstEitherK: <A, E, B>(
  f: (a: A) => E.Either<E, B>,
) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstEitherKW​

Alias of tapEither.

Less strict version of chainFirstEitherK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainFirstEitherKW: <A, E2, B>(
  f: (a: A) => Either<E2, B>,
) => <R, E1>(ma: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstIOK​

Alias of tapIO.

Signature​

export declare const chainFirstIOK: <A, B>(
  f: (a: A) => IO<B>,
) => <R, E>(first: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstReaderEitherK​

Alias of tapReaderEither.

Signature​

export declare const chainFirstReaderEitherK: <R, E, A, B>(
  f: (a: A) => ReaderEither<R, E, B>,
) => (ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstReaderEitherKW​

Alias of tapReaderEither.

Less strict version of chainFirstReaderEitherK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainFirstReaderEitherKW: <R2, E2, A, B>(
  f: (a: A) => ReaderEither<R2, E2, B>,
) => <R1, E1>(ma: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstReaderIOK​

Alias of tapReaderIO.

Signature​

export declare const chainFirstReaderIOK: <A, R, B>(
  f: (a: A) => ReaderIO<R, B>,
) => <E>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstReaderIOKW​

Alias of tapReaderIO.

Less strict version of chainFirstReaderIOK.

Signature​

export declare const chainFirstReaderIOKW: <A, R2, B>(
  f: (a: A) => ReaderIO<R2, B>,
) => <R1, E>(ma: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstReaderK​

Alias of tapReader.

Signature​

export declare const chainFirstReaderK: <A, R, B>(
  f: (a: A) => R.Reader<R, B>,
) => <E>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstReaderKW​

Alias of tapReader.

Less strict version of chainFirstReaderK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainFirstReaderKW: <A, R1, B>(
  f: (a: A) => R.Reader<R1, B>,
) => <R2, E>(ma: ReaderTaskEither<R2, E, A>) => ReaderTaskEither<R1 & R2, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstReaderTaskK​

Alias of tapReaderTask.

Signature​

export declare const chainFirstReaderTaskK: <A, R, B>(
  f: (a: A) => RT.ReaderTask<R, B>,
) => <E>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstReaderTaskKW​

Alias of tapReaderTask.

Less strict version of chainFirstReaderTaskK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainFirstReaderTaskKW: <A, R2, B>(
  f: (a: A) => RT.ReaderTask<R2, B>,
) => <R1, E>(ma: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstTaskEitherK​

Alias of tapTaskEither.

Signature​

export declare const chainFirstTaskEitherK: <E, A, B>(
  f: (a: A) => TaskEither<E, B>,
) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstTaskEitherKW​

Alias of tapTaskEither.

Less strict version of chainFirstTaskEitherK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainFirstTaskEitherKW: <E2, A, B>(
  f: (a: A) => TaskEither<E2, B>,
) => <R, E1>(ma: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstTaskK​

Alias of tapTask.

Signature​

export declare const chainFirstTaskK: <A, B>(
  f: (a: A) => T.Task<B>,
) => <R, E>(first: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainFirstW​

Alias of tap.

Signature​

export declare const chainFirstW: <R2, E2, A, B>(
  f: (a: A) => ReaderTaskEither<R2, E2, B>,
) => <R1, E1>(ma: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainIOEitherK​

Alias of flatMapIOEither.

Signature​

export declare const chainIOEitherK: <E, A, B>(
  f: (a: A) => IOEither<E, B>,
) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainIOEitherKW​

Alias of flatMapIOEither.

Less strict version of chainIOEitherK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainIOEitherKW: <E2, A, B>(
  f: (a: A) => IOEither<E2, B>,
) => <R, E1>(ma: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainIOK​

Alias of flatMapIO.

Signature​

export declare const chainIOK: <A, B>(
  f: (a: A) => IO<B>,
) => <R, E>(first: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainNullableK​

Use flatMapNullable.

Signature​

export declare const chainNullableK: <E>(
  e: E,
) => <A, B>(
  f: (a: A) => B | null | undefined,
) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, NonNullable<B>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainOptionK​

Use flatMapOption.

Signature​

export declare const chainOptionK: <E>(
  onNone: LazyArg<E>,
) => <A, B>(f: (a: A) => Option<B>) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainOptionKW​

Use flatMapOption.

Signature​

export declare const chainOptionKW: <E2>(
  onNone: LazyArg<E2>,
) => <A, B>(f: (a: A) => Option<B>) => <R, E1>(ma: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainReaderEitherK​

Alias of flatMapReaderEither.

Signature​

export declare const chainReaderEitherK: <R, E, A, B>(
  f: (a: A) => ReaderEither<R, E, B>,
) => (ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainReaderEitherKW​

Alias of flatMapReaderEither.

Less strict version of chainReaderEitherK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainReaderEitherKW: <R2, E2, A, B>(
  f: (a: A) => ReaderEither<R2, E2, B>,
) => <R1, E1>(ma: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainReaderIOK​

Alias of flatMapReaderIO.

Signature​

export declare const chainReaderIOK: <A, R, B>(
  f: (a: A) => ReaderIO<R, B>,
) => <E>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainReaderIOKW​

Alias of flatMapReaderIO.

Less strict version of chainReaderIOK.

Signature​

export declare const chainReaderIOKW: <A, R2, B>(
  f: (a: A) => ReaderIO<R2, B>,
) => <R1, E>(ma: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainReaderK​

Alias of flatMapReader.

Signature​

export declare const chainReaderK: <A, R, B>(
  f: (a: A) => Reader<R, B>,
) => <E>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainReaderKW​

Alias of flatMapReader.

Less strict version of chainReaderK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainReaderKW: <A, R1, B>(
  f: (a: A) => R.Reader<R1, B>,
) => <R2, E>(ma: ReaderTaskEither<R2, E, A>) => ReaderTaskEither<R1 & R2, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainReaderTaskK​

Alias of flatMapReaderTask.

Signature​

export declare const chainReaderTaskK: <A, R, B>(
  f: (a: A) => RT.ReaderTask<R, B>,
) => <E>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainReaderTaskKW​

Alias of flatMapReaderTask.

Less strict version of chainReaderTaskK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainReaderTaskKW: <A, R2, B>(
  f: (a: A) => RT.ReaderTask<R2, B>,
) => <R1, E>(ma: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainTaskEitherK​

Alias of flatMapTaskEither.

Signature​

export declare const chainTaskEitherK: <E, A, B>(
  f: (a: A) => TaskEither<E, B>,
) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainTaskEitherKW​

Alias of flatMapTaskEither.

Less strict version of chainTaskEitherK.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const chainTaskEitherKW: <E2, A, B>(
  f: (a: A) => TaskEither<E2, B>,
) => <R, E1>(ma: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainTaskK​

Alias of flatMapTask.

Signature​

export declare const chainTaskK: <A, B>(
  f: (a: A) => T.Task<B>,
) => <R, E>(first: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

chainW​

Alias of flatMap.

Signature​

export declare const chainW: <R2, E2, A, B>(
  f: (a: A) => ReaderTaskEither<R2, E2, B>,
) => <R1, E1>(ma: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromNullableK​

Use liftNullable.

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromOptionK​

Use liftOption.

Signature​

export declare const fromOptionK: <E>(
  onNone: LazyArg<E>,
) => <A extends ReadonlyArray<unknown>, B>(
  f: (...a: A) => Option<B>,
) => <R = unknown>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

mapLeft​

Alias of mapError.

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

orElseFirst​

Alias of tapError.

Signature​

export declare const orElseFirst: <E, R, B>(
  onLeft: (e: E) => ReaderTaskEither<R, E, B>,
) => <A>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

orElseFirstW​

Alias of tapError.

Signature​

export declare const orElseFirstW: <E1, R2, E2, B>(
  onLeft: (e: E1) => ReaderTaskEither<R2, E2, B>,
) => <R1, A>(ma: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Lifting​

fromEitherK​

Signature​

export declare const fromEitherK: <E, A extends ReadonlyArray<unknown>, B>(
  f: (...a: A) => E.Either<E, B>,
) => <R = unknown>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromIOEitherK​

Signature​

export declare const fromIOEitherK: <E, A extends readonly unknown[], B>(
  f: (...a: A) => IOEither<E, B>,
) => <R = unknown>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromIOK​

Signature​

export declare const fromIOK: <A extends ReadonlyArray<unknown>, B>(
  f: (...a: A) => IO<B>,
) => <R = unknown, E = never>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromPredicate​

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromReaderEitherK​

Signature​

export declare const fromReaderEitherK: <R, E, A extends readonly unknown[], B>(
  f: (...a: A) => ReaderEither<R, E, B>,
) => (...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromReaderIOK​

Signature​

export declare const fromReaderIOK: <A extends readonly unknown[], R, B>(
  f: (...a: A) => ReaderIO<R, B>,
) => <E = never>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromReaderK​

Signature​

export declare const fromReaderK: <A extends ReadonlyArray<unknown>, R, B>(
  f: (...a: A) => Reader<R, B>,
) => <E = never>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromReaderTaskK​

Signature​

export declare const fromReaderTaskK: <A extends readonly unknown[], R, B>(
  f: (...a: A) => RT.ReaderTask<R, B>,
) => <E = never>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromTaskEitherK​

Signature​

export declare const fromTaskEitherK: <E, A extends readonly unknown[], B>(
  f: (...a: A) => TE.TaskEither<E, B>,
) => <R = unknown>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fromTaskK​

Signature​

export declare const fromTaskK: <A extends ReadonlyArray<unknown>, B>(
  f: (...a: A) => T.Task<B>,
) => <R = unknown, E = never>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

liftNullable​

Signature​

export declare const liftNullable: <A extends ReadonlyArray<unknown>, B, E>(
  f: (...a: A) => B | null | undefined,
  onNullable: (...a: A) => E,
) => <R>(...a: A) => ReaderTaskEither<R, E, NonNullable<B>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

liftOption​

Signature​

export declare const liftOption: <A extends ReadonlyArray<unknown>, B, E>(
  f: (...a: A) => Option<B>,
  onNone: (...a: A) => E,
) => <R>(...a: A) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Mapping​

as​

Maps the Right value of this ReaderTaskEither to the specified constant value.

Signature​

export declare const as: {
  <A>(a: A): <R, E, _>(self: ReaderTaskEither<R, E, _>) => ReaderTaskEither<R, E, A>
  <R, E, _, A>(self: ReaderTaskEither<R, E, _>, a: A): ReaderTaskEither<R, E, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

asUnit​

Maps the Right value of this ReaderTaskEither to the void constant value.

Signature​

export declare const asUnit: <R, E, _>(self: ReaderTaskEither<R, E, _>) => ReaderTaskEither<R, E, void>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flap​

Signature​

export declare const flap: <A>(a: A) => <R, E, B>(fab: ReaderTaskEither<R, E, (a: A) => B>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

map​

map can be used to turn functions (a: A) => B into functions (fa: F<A>) => F<B> whose argument and return types use the type constructor F to represent some computational context.

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Model​

ReaderTaskEither​

Signature​

export interface ReaderTaskEither<R, E, A> {
  (r: R): TaskEither<E, A>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Pattern matching​

fold​

Alias of matchE.

Signature​

export declare const fold: <R, E, A, B>(
  onLeft: (e: E) => RT.ReaderTask<R, B>,
  onRight: (a: A) => RT.ReaderTask<R, B>,
) => (ma: ReaderTaskEither<R, E, A>) => RT.ReaderTask<R, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

foldW​

Alias of matchEW.

Signature​

export declare const foldW: <E, R2, B, A, R3, C>(
  onLeft: (e: E) => RT.ReaderTask<R2, B>,
  onRight: (a: A) => RT.ReaderTask<R3, C>,
) => <R1>(ma: ReaderTaskEither<R1, E, A>) => RT.ReaderTask<R1 & R2 & R3, B | C>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

match​

Signature​

export declare const match: <E, B, A>(
  onLeft: (e: E) => B,
  onRight: (a: A) => B,
) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTask<R, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

matchE​

The E suffix (short for Effect) means that the handlers return an effect (ReaderTask).

Signature​

export declare const matchE: <R, E, A, B>(
  onLeft: (e: E) => ReaderTask<R, B>,
  onRight: (a: A) => ReaderTask<R, B>,
) => (ma: ReaderTaskEither<R, E, A>) => ReaderTask<R, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

matchEW​

Less strict version of matchE.

The W suffix (short for Widening) means that the handler return types will be merged.

Signature​

export declare const matchEW: <E, R2, B, A, R3, C>(
  onLeft: (e: E) => ReaderTask<R2, B>,
  onRight: (a: A) => ReaderTask<R3, C>,
) => <R1>(ma: ReaderTaskEither<R1, E, A>) => ReaderTask<R1 & R2 & R3, B | C>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

matchW​

Less strict version of match.

The W suffix (short for Widening) means that the handler return types will be merged.

Signature​

export declare const matchW: <E, B, A, C>(
  onLeft: (e: E) => B,
  onRight: (a: A) => C,
) => <R>(ma: ReaderTaskEither<R, E, A>) => ReaderTask<R, B | C>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Sequencing​

flatMap​

Signature​

export declare const flatMap: {
  <A, R2, E2, B>(
    f: (a: A) => ReaderTaskEither<R2, E2, B>,
  ): <R1, E1>(ma: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, B>
  <R1, E1, A, R2, E2, B>(
    ma: ReaderTaskEither<R1, E1, A>,
    f: (a: A) => ReaderTaskEither<R2, E2, B>,
  ): ReaderTaskEither<R1 & R2, E1 | E2, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapEither​

Signature​

export declare const flatMapEither: {
  <A, E2, B>(f: (a: A) => E.Either<E2, B>): <R, E1>(self: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, B>
  <R, E1, A, E2, B>(self: ReaderTaskEither<R, E1, A>, f: (a: A) => E.Either<E2, B>): ReaderTaskEither<R, E1 | E2, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapIO​

Signature​

export declare const flatMapIO: {
  <A, B>(f: (a: A) => IO<B>): <R, E>(self: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>
  <R, E, A, B>(self: ReaderTaskEither<R, E, A>, f: (a: A) => IO<B>): ReaderTaskEither<R, E, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapIOEither​

Signature​

export declare const flatMapIOEither: {
  <A, E2, B>(f: (a: A) => IOEither<E2, B>): <R, E1>(self: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, B>
  <R, E1, A, E2, B>(self: ReaderTaskEither<R, E1, A>, f: (a: A) => IOEither<E2, B>): ReaderTaskEither<R, E1 | E2, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapNullable​

Signature​

export declare const flatMapNullable: {
  <A, B, E2>(
    f: (a: A) => B | null | undefined,
    onNullable: (a: A) => E2,
  ): <R, E1>(self: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E2 | E1, NonNullable<B>>
  <R, E1, A, B, E2>(
    self: ReaderTaskEither<R, E1, A>,
    f: (a: A) => B | null | undefined,
    onNullable: (a: A) => E2,
  ): ReaderTaskEither<R, E1 | E2, NonNullable<B>>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapOption​

Signature​

export declare const flatMapOption: {
  <A, B, E2>(
    f: (a: A) => Option<B>,
    onNone: (a: A) => E2,
  ): <R, E1>(self: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E2 | E1, B>
  <R, E1, A, B, E2>(
    self: ReaderTaskEither<R, E1, A>,
    f: (a: A) => Option<B>,
    onNone: (a: A) => E2,
  ): ReaderTaskEither<R, E1 | E2, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapReader​

Signature​

export declare const flatMapReader: {
  <A, R2, B>(f: (a: A) => Reader<R2, B>): <R1, E>(self: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, B>
  <R1, E, A, R2, B>(self: ReaderTaskEither<R1, E, A>, f: (a: A) => Reader<R2, B>): ReaderTaskEither<R1 & R2, E, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapReaderEither​

Signature​

export declare const flatMapReaderEither: {
  <A, R2, E2, B>(
    f: (a: A) => ReaderEither<R2, E2, B>,
  ): <R1, E1>(self: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, B>
  <R1, E1, A, R2, E2, B>(
    self: ReaderTaskEither<R1, E1, A>,
    f: (a: A) => ReaderEither<R2, E2, B>,
  ): ReaderTaskEither<R1 & R2, E1 | E2, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapReaderIO​

Signature​

export declare const flatMapReaderIO: {
  <A, R2, B>(f: (a: A) => ReaderIO<R2, B>): <R1, E>(self: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, B>
  <R1, E, A, R2, B>(self: ReaderTaskEither<R1, E, A>, f: (a: A) => ReaderIO<R2, B>): ReaderTaskEither<R1 & R2, E, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapReaderTask​

Signature​

export declare const flatMapReaderTask: {
  <A, R2, B>(
    f: (a: A) => ReaderTask<R2, B>,
  ): <R1, E>(self: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R1 & R2, E, B>
  <R1, E, A, R2, B>(self: ReaderTaskEither<R1, E, A>, f: (a: A) => ReaderTask<R2, B>): ReaderTaskEither<R1 & R2, E, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapTask​

Signature​

export declare const flatMapTask: {
  <A, B>(f: (a: A) => Task<B>): <R, E>(self: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>
  <R, E, A, B>(self: ReaderTaskEither<R, E, A>, f: (a: A) => Task<B>): ReaderTaskEither<R, E, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatMapTaskEither​

Signature​

export declare const flatMapTaskEither: {
  <A, E2, B>(
    f: (a: A) => TaskEither<E2, B>,
  ): <R, E1>(self: ReaderTaskEither<R, E1, A>) => ReaderTaskEither<R, E1 | E2, B>
  <R, E1, A, E2, B>(self: ReaderTaskEither<R, E1, A>, f: (a: A) => TaskEither<E2, B>): ReaderTaskEither<R, E1 | E2, B>
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flatten​

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

flattenW​

Less strict version of flatten.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const flattenW: <R1, E1, R2, E2, A>(
  mma: ReaderTaskEither<R1, E1, ReaderTaskEither<R2, E2, A>>,
) => ReaderTaskEither<R1 & R2, E1 | E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Traversing​

sequenceArray​

Equivalent to ReadonlyArray#sequence(Applicative).

Signature​

export declare const sequenceArray: <R, E, A>(
  arr: ReadonlyArray<ReaderTaskEither<R, E, A>>,
) => ReaderTaskEither<R, E, ReadonlyArray<A>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

sequenceSeqArray​

Equivalent to ReadonlyArray#sequence(ApplicativeSeq).

Signature​

export declare const sequenceSeqArray: <R, E, A>(
  arr: ReadonlyArray<ReaderTaskEither<R, E, A>>,
) => ReaderTaskEither<R, E, ReadonlyArray<A>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

traverseArray​

Equivalent to ReadonlyArray#traverse(Applicative).

Signature​

export declare const traverseArray: <R, E, A, B>(
  f: (a: A) => ReaderTaskEither<R, E, B>,
) => (as: readonly A[]) => ReaderTaskEither<R, E, readonly B[]>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

traverseArrayWithIndex​

Equivalent to ReadonlyArray#traverseWithIndex(Applicative).

Signature​

export declare const traverseArrayWithIndex: <R, E, A, B>(
  f: (index: number, a: A) => ReaderTaskEither<R, E, B>,
) => (as: ReadonlyArray<A>) => ReaderTaskEither<R, E, ReadonlyArray<B>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

traverseReadonlyArrayWithIndex​

Equivalent to ReadonlyArray#traverseWithIndex(ApplicativePar).

Signature​

export declare const traverseReadonlyArrayWithIndex: <A, R, E, B>(
  f: (index: number, a: A) => ReaderTaskEither<R, E, B>,
) => (as: readonly A[]) => ReaderTaskEither<R, E, readonly B[]>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

traverseReadonlyArrayWithIndexSeq​

Equivalent to ReadonlyArray#traverseWithIndex(ApplicativeSeq).

Signature​

export declare const traverseReadonlyArrayWithIndexSeq: <A, R, E, B>(
  f: (index: number, a: A) => ReaderTaskEither<R, E, B>,
) => (as: readonly A[]) => ReaderTaskEither<R, E, readonly B[]>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

traverseReadonlyNonEmptyArrayWithIndex​

Equivalent to ReadonlyNonEmptyArray#traverseWithIndex(ApplicativePar).

Signature​

export declare const traverseReadonlyNonEmptyArrayWithIndex: <A, R, E, B>(
  f: (index: number, a: A) => ReaderTaskEither<R, E, B>,
) => (as: ReadonlyNonEmptyArray<A>) => ReaderTaskEither<R, E, ReadonlyNonEmptyArray<B>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

traverseReadonlyNonEmptyArrayWithIndexSeq​

Equivalent to ReadonlyNonEmptyArray#traverseWithIndex(ApplicativeSeq).

Signature​

export declare const traverseReadonlyNonEmptyArrayWithIndexSeq: <A, R, E, B>(
  f: (index: number, a: A) => ReaderTaskEither<R, E, B>,
) => (as: ReadonlyNonEmptyArray<A>) => ReaderTaskEither<R, E, ReadonlyNonEmptyArray<B>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

traverseSeqArray​

Equivalent to ReadonlyArray#traverse(ApplicativeSeq).

Signature​

export declare const traverseSeqArray: <R, E, A, B>(
  f: (a: A) => ReaderTaskEither<R, E, B>,
) => (as: readonly A[]) => ReaderTaskEither<R, E, readonly B[]>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

traverseSeqArrayWithIndex​

Equivalent to ReadonlyArray#traverseWithIndex(ApplicativeSeq).

Signature​

export declare const traverseSeqArrayWithIndex: <R, E, A, B>(
  f: (index: number, a: A) => ReaderTaskEither<R, E, B>,
) => (as: ReadonlyArray<A>) => ReaderTaskEither<R, E, ReadonlyArray<B>>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Type lambdas​

URI​

Signature​

export type URI = typeof URI

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

URI​

Signature​

export declare const URI = 'ReaderTaskEither'

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Utilities​

ApT​

Signature​

export declare const ApT: ReaderTaskEither<unknown, never, readonly []>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

ap​

Signature​

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

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

apFirst​

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

Signature​

export declare const apFirst: <R, E, B>(
  second: ReaderTaskEither<R, E, B>,
) => <A>(first: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

apFirstW​

Less strict version of apFirst.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const apFirstW: <R2, E2, B>(
  second: ReaderTaskEither<R2, E2, B>,
) => <R1, E1, A>(first: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

apSecond​

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

Signature​

export declare const apSecond: <R, E, B>(
  second: ReaderTaskEither<R, E, B>,
) => <A>(first: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

apSecondW​

Less strict version of apSecond.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const apSecondW: <R2, E2, B>(
  second: ReaderTaskEither<R2, E2, B>,
) => <R1, E1, A>(first: ReaderTaskEither<R1, E1, A>) => ReaderTaskEither<R1 & R2, E1 | E2, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

apW​

Less strict version of ap.

The W suffix (short for Widening) means that the environment types and the error types will be merged.

Signature​

export declare const apW: <R2, E2, A>(
  fa: ReaderTaskEither<R2, E2, A>,
) => <R1, E1, B>(fab: ReaderTaskEither<R1, E1, (a: A) => B>) => ReaderTaskEither<R1 & R2, E1 | E2, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

bracket​

Make sure that a resource is cleaned up in the event of an exception (). The release action is called regardless of whether the body action throws () or returns.

(*) i.e. returns a Left

Signature​

export declare function bracket<R, E, A, B>(
  acquire: ReaderTaskEither<R, E, A>,
  use: (a: A) => ReaderTaskEither<R, E, B>,
  release: (a: A, e: Either<E, B>) => ReaderTaskEither<R, E, void>,
): ReaderTaskEither<R, E, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

bracketW​

Less strict version of bracket.

Signature​

export declare function bracketW<R1, E1, A, R2, E2, B, R3, E3>(
  acquire: ReaderTaskEither<R1, E1, A>,
  use: (a: A) => ReaderTaskEither<R2, E2, B>,
  release: (a: A, e: Either<E2, B>) => ReaderTaskEither<R3, E3, void>,
): ReaderTaskEither<R1 & R2 & R3, E1 | E2 | E3, B>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

do​

Signature​

export declare const do_: <MA extends ReaderTaskEitherIterable<any, any, any>, A>(
  yieldFunction: (
    unwrap: <R, E, A>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEitherIterable<R, E, A>,
  ) => Generator<MA, A>,
) => ReaderTaskEither<
  _.UnionToIntersection<MA extends ReaderTaskEitherIterable<infer R, any, any> ? R : never>,
  MA extends ReaderTaskEitherIterable<any, infer E, any> ? E : never,
  A
>

getApplyMonoid​

Use getApplicativeMonoid instead.

Signature​

export declare const getApplyMonoid: <R, E, A>(M: Monoid<A>) => Monoid<ReaderTaskEither<R, E, A>>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getApplySemigroup​

Use getApplySemigroup instead.

Semigroup returning the left-most Left value. If both operands are Rights then the inner values are concatenated using the provided Semigroup

Signature​

export declare const getApplySemigroup: <R, E, A>(S: Semigroup<A>) => Semigroup<ReaderTaskEither<R, E, A>>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getSemigroup​

Use getApplySemigroup instead.

Signature​

export declare const getSemigroup: <R, E, A>(S: Semigroup<A>) => Semigroup<ReaderTaskEither<R, E, A>>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

let​

Signature​

export declare const let_: <N extends string, A, B>(
  name: Exclude<N, keyof A>,
  f: (a: A) => B,
) => <R, E>(
  fa: ReaderTaskEither<R, E, A>,
) => ReaderTaskEither<R, E, { readonly [K in N | keyof A]: K extends keyof A ? A[K] : B }>

local​

Changes the value of the local context during the execution of the action ma (similar to Contravariant's contramap).

Signature​

export declare const local: <R2, R1>(
  f: (r2: R2) => R1,
) => <E, A>(ma: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R2, E, A>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

readerTaskEither​

This instance is deprecated, use small, specific instances instead. For example if a function needs a Functor instance, pass RTE.Functor instead of RTE.readerTaskEither

Signature​

export declare const readerTaskEither: Monad3<URI> & Bifunctor3<URI> & Alt3<URI> & MonadTask3<URI> & MonadThrow3<URI>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

readerTaskEitherSeq​

This instance is deprecated, use small, specific instances instead. For example if a function needs a Functor instance, pass RTE.Functor instead of RTE.readerTaskEitherSeq

Signature​

export declare const readerTaskEitherSeq: typeof readerTaskEither

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

run​

Signature​

export declare function run<R, E, A>(ma: ReaderTaskEither<R, E, A>, r: R): Promise<Either<E, A>>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

swap​

Signature​

export declare const swap: <R, E, A>(ma: ReaderTaskEither<R, E, A>) => ReaderTaskEither<R, A, E>

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

throwError​

Signature​

export declare const throwError: MonadThrow3<URI>['throwError']

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti