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ReaderIO

Instances​

Combinators​

Constructors​

Conversions​

Do notation​

Instance methods​

Legacy​

Lifting​

Mapping​

Model​

Sequencing​

Traversing​

Type lambdas​

Utilities​

Instances​

Applicative​

Signature​

export declare const Applicative: Applicative2<URI>

Details​

  • Added in 0.1.0

License​

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

Apply​

Signature​

export declare const Apply: Apply2<URI>

Details​

  • Added in 0.1.0

License​

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

Chain​

Signature​

export declare const Chain: chainable.Chain2<URI>

Details​

  • Added in 0.1.0

License​

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

ChainRec​

ChainRec for ReaderIO

Signature​

export declare const ChainRec: ChainRec2<URI>

Details​

  • Added in 0.1.0

License​

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

FromIO​

Signature​

export declare const FromIO: FromIO2<URI>

Details​

  • Added in 0.1.0

License​

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

FromReader​

Signature​

export declare const FromReader: FromReader2<URI>

Details​

  • Added in 0.1.0

License​

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

Functor​

Signature​

export declare const Functor: Functor2<URI>

Details​

  • Added in 0.1.0

License​

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

Monad​

Signature​

export declare const Monad: Monad2<URI>

Details​

  • Added in 0.1.0

License​

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

MonadIO​

Signature​

export declare const MonadIO: MonadIO2<URI>

Details​

  • Added in 0.1.0

License​

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

Pointed​

Signature​

export declare const Pointed: Pointed2<URI>

Details​

  • Added in 0.1.0

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, A, R2, _>(self: ReaderIO<R1, A>, f: (a: A) => ReaderIO<R2, _>): ReaderIO<R1 & R2, A>
  <A, R2, _>(f: (a: A) => ReaderIO<R2, _>): <R1>(self: ReaderIO<R1, A>) => ReaderIO<R2 & R1, A>
}

Details​

  • Added in 0.1.0

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>(self: ReaderIO<R, A>) => ReaderIO<R, A>
  <R, A, _>(self: ReaderIO<R, A>, f: (a: A) => IO<_>): ReaderIO<R, A>
}

Details​

  • Added in 0.1.0

Example​

import { pipe } from '@fp-tx/core/function'
import * as RIO from '@fp-tx/core/ReaderIO'
import * as Console from '@fp-tx/core/Console'

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

async function test() {
  assert.deepStrictEqual(effect('fp-ts')(), '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: {
  <R2, A, _>(f: (a: A) => Reader<R2, _>): <R1>(self: ReaderIO<R1, A>) => ReaderIO<R1 & R2, A>
  <R1, A, R2, _>(self: ReaderIO<R1, A>, f: (a: A) => Reader<R2, _>): ReaderIO<R1 & R2, 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>() => ReaderIO<R, 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 ReaderIO.

Signature​

export declare const asks: <R, A>(f: (r: R) => A) => ReaderIO<R, A>

Details​

  • Added in 0.1.0

License​

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

asksReaderIO​

Effectfully accesses the environment.

Signature​

export declare const asksReaderIO: <R, A>(f: (r: R) => ReaderIO<R, A>) => ReaderIO<R, A>

Details​

  • Added in 0.1.0

License​

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

asksReaderIOW​

Less strict version of asksReaderIO.

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

Signature​

export declare const asksReaderIOW: <R1, R2, A>(f: (r1: R1) => ReaderIO<R2, A>) => ReaderIO<R1 & R2, A>

Details​

  • Added in 0.1.0

License​

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

of​

Signature​

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

Details​

  • Added in 0.1.0

License​

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

Conversions​

fromIO​

Signature​

export declare const fromIO: <A, R = unknown>(fa: IO<A>) => ReaderIO<R, A>

Details​

  • Added in 0.1.0

License​

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

fromReader​

Signature​

export declare const fromReader: <R, A>(fa: Reader<R, A>) => ReaderIO<R, A>

Details​

  • Added in 0.1.0

License​

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

Do notation​

Do​

Signature​

export declare const Do: ReaderIO<unknown, {}>

Details​

  • Added in 0.1.0

License​

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

apS​

Signature​

export declare const apS: <N extends string, A, E, B>(
  name: Exclude<N, keyof A>,
  fb: ReaderIO<E, B>,
) => (fa: ReaderIO<E, A>) => ReaderIO<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 will be merged.

Signature​

export declare const apSW: <N extends string, A, R2, B>(
  name: Exclude<N, keyof A>,
  fb: ReaderIO<R2, B>,
) => <R1>(fa: ReaderIO<R1, A>) => ReaderIO<
  R1 & R2,
  {
    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, E, B>(
  name: Exclude<N, keyof A>,
  f: (a: A) => ReaderIO<E, B>,
) => (ma: ReaderIO<E, A>) => ReaderIO<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,
) => <E, A>(fa: ReaderIO<E, A>) => ReaderIO<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 will be merged.

Signature​

export declare const bindW: <N extends string, A, R2, B>(
  name: Exclude<N, keyof A>,
  f: (a: A) => ReaderIO<R2, B>,
) => <R1>(fa: ReaderIO<R1, A>) => ReaderIO<
  R1 & R2,
  {
    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

Instance methods​

chainRec​

Signature​

export declare const chainRec: ChainRec2<URI>['chainRec']

Details​

  • Added in 0.1.0

License​

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

Legacy​

chain​

Alias of flatMap.

Signature​

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

Details​

  • Added in 0.1.0

License​

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

chainFirst​

Alias of tap.

Signature​

export declare const chainFirst: <A, R, B>(f: (a: A) => ReaderIO<R, B>) => (first: ReaderIO<R, A>) => ReaderIO<R, 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) => I.IO<B>) => <E>(first: ReaderIO<E, A>) => ReaderIO<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>) => (ma: ReaderIO<R, A>) => ReaderIO<R, 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 will be merged.

Signature​

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

Details​

  • Added in 0.1.0

License​

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

chainFirstW​

Alias of tap.

Signature​

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

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) => I.IO<B>) => <E>(first: ReaderIO<E, A>) => ReaderIO<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) => R.Reader<R, B>) => (ma: ReaderIO<R, A>) => ReaderIO<R, 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 will be merged.

Signature​

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

Details​

  • Added in 0.1.0

License​

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

chainW​

Alias of flatMap.

Signature​

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

Details​

  • Added in 0.1.0

License​

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

Lifting​

fromIOK​

Signature​

export declare const fromIOK: <A extends ReadonlyArray<unknown>, B>(
  f: (...a: A) => I.IO<B>,
) => <R = unknown>(...a: A) => ReaderIO<R, 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) => R.Reader<R, B>,
) => (...a: A) => ReaderIO<R, B>

Details​

  • Added in 0.1.0

License​

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

Mapping​

as​

Maps the value to the specified constant value.

Signature​

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

Details​

  • Added in 0.1.0

License​

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

asUnit​

Maps the value to the void constant value.

Signature​

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

Details​

  • Added in 0.1.0

License​

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

flap​

Signature​

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

Details​

  • Added in 0.1.0

License​

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

Model​

ReaderIO​

Signature​

export interface ReaderIO<R, A> {
  (r: R): I.IO<A>
}

Details​

  • Added in 0.1.0

License​

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

Sequencing​

flatMap​

Signature​

export declare const flatMap: {
  <A, R2, B>(f: (a: A) => ReaderIO<R2, B>): <R1>(ma: ReaderIO<R1, A>) => ReaderIO<R1 & R2, B>
  <R1, A, R2, B>(ma: ReaderIO<R1, A>, f: (a: A) => ReaderIO<R2, B>): ReaderIO<R1 & R2, 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>(self: ReaderIO<R, A>) => ReaderIO<R, B>
  <R, A, B>(self: ReaderIO<R, A>, f: (a: A) => IO<B>): ReaderIO<R, 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>(self: ReaderIO<R1, A>) => ReaderIO<R1 & R2, B>
  <R1, A, R2, B>(self: ReaderIO<R1, A>, f: (a: A) => Reader<R2, B>): ReaderIO<R1 & R2, B>
}

Details​

  • Added in 0.1.0

License​

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

flatten​

Signature​

export declare const flatten: <R, A>(mma: ReaderIO<R, ReaderIO<R, A>>) => ReaderIO<R, 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 will be merged.

Signature​

export declare const flattenW: <R1, R2, A>(mma: ReaderIO<R1, ReaderIO<R2, A>>) => ReaderIO<R1 & R2, 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, A>(arr: ReadonlyArray<ReaderIO<R, A>>) => ReaderIO<R, 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: <A, R, B>(
  f: (a: A) => ReaderIO<R, B>,
) => (as: readonly A[]) => ReaderIO<R, 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: <A, R, B>(
  f: (index: number, a: A) => ReaderIO<R, B>,
) => (as: ReadonlyArray<A>) => ReaderIO<R, ReadonlyArray<B>>

Details​

  • Added in 0.1.0

License​

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

traverseReadonlyArrayWithIndex​

Equivalent to ReadonlyArray#traverseWithIndex(Applicative).

Signature​

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

Details​

  • Added in 0.1.0

License​

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

traverseReadonlyNonEmptyArrayWithIndex​

Equivalent to ReadonlyNonEmptyArray#traverseWithIndex(Applicative).

Signature​

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

Details​

  • Added in 0.1.0

License​

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

Utilities​

ApT​

Signature​

export declare const ApT: ReaderIO<unknown, readonly []>

Details​

  • Added in 0.1.0

License​

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

ap​

Signature​

export declare const ap: <R, A>(fa: ReaderIO<R, A>) => <B>(fab: ReaderIO<R, (a: A) => B>) => ReaderIO<R, 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: <E, B>(second: ReaderIO<E, B>) => <A>(first: ReaderIO<E, A>) => ReaderIO<E, 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: <E, B>(second: ReaderIO<E, B>) => <A>(first: ReaderIO<E, A>) => ReaderIO<E, 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 will be merged.

Signature​

export declare const apW: <R2, A>(
  fa: ReaderIO<R2, A>,
) => <R1, B>(fab: ReaderIO<R1, (a: A) => B>) => ReaderIO<R1 & R2, B>

Details​

  • Added in 0.1.0

License​

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

do​

Signature​

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

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) => <A>(ma: ReaderIO<R1, A>) => ReaderIO<R2, A>

Details​

  • Added in 0.1.0

License​

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