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IoOption

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: Alt1<URI>

Details​

  • Added in 0.1.0

License​

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

Alternative​

Signature​

export declare const Alternative: Alternative1<URI>

Details​

  • Added in 0.1.0

License​

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

Applicative​

Signature​

export declare const Applicative: Applicative1<URI>

Details​

  • Added in 0.1.0

License​

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

Apply​

Signature​

export declare const Apply: Apply1<URI>

Details​

  • Added in 0.1.0

License​

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

Chain​

Signature​

export declare const Chain: chainable.Chain1<URI>

Details​

  • Added in 0.1.0

License​

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

ChainRec​

ChainRec for IOOption

Signature​

export declare const ChainRec: ChainRec1<URI>

Details​

  • Added in 0.1.0

License​

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

Compactable​

Signature​

export declare const Compactable: Compactable1<URI>

Details​

  • Added in 0.1.0

License​

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

Filterable​

Signature​

export declare const Filterable: Filterable1<URI>

Details​

  • Added in 0.1.0

License​

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

FromEither​

Signature​

export declare const FromEither: FromEither1<URI>

Details​

  • Added in 0.1.0

License​

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

FromIO​

Signature​

export declare const FromIO: FromIO1<URI>

Details​

  • Added in 0.1.0

License​

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

Functor​

Signature​

export declare const Functor: Functor1<URI>

Details​

  • Added in 0.1.0

License​

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

Monad​

Signature​

export declare const Monad: Monad1<URI>

Details​

  • Added in 0.1.0

License​

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

MonadIO​

Signature​

export declare const MonadIO: MonadIO1<URI>

Details​

  • Added in 0.1.0

License​

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

MonadThrow​

Signature​

export declare const MonadThrow: MonadThrow1<URI>

Details​

  • Added in 0.1.0

License​

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

Pointed​

Signature​

export declare const Pointed: Pointed1<URI>

Details​

  • Added in 0.1.0

License​

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

Zero​

Signature​

export declare const Zero: Zero1<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: {
  <A, _>(self: IOOption<A>, f: (a: A) => IOOption<_>): IOOption<A>
  <A, _>(f: (a: A) => IOOption<_>): (self: IOOption<A>) => IOOption<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, E, _>(f: (a: A) => Either<E, _>): (self: IOOption<A>) => IOOption<A>
  <A, E, _>(self: IOOption<A>, f: (a: A) => Either<E, _>): IOOption<A>
}

Details​

  • Added in 0.1.0

Example​

import { pipe } from '@fp-tx/core/function'
import * as IOO from '@fp-tx/core/IOOption'
import * as O from '@fp-tx/core/Option'
import * as E from '@fp-tx/core/Either'

const compute = (value: number) =>
  pipe(
    IOO.of(value),
    IOO.tapEither(value => (value > 0 ? E.right('ok') : E.left('error'))),
  )

assert.deepStrictEqual(compute(1)(), O.of(1))
assert.deepStrictEqual(compute(-1)(), O.none)

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

Details​

  • Added in 0.1.0

Example​

import { pipe } from '@fp-tx/core/function'
import * as IOO from '@fp-tx/core/IOOption'
import * as O from '@fp-tx/core/Option'
import * as Console from '@fp-tx/core/Console'

// Will produce `Hello, fp-ts` to the stdout
const effectA = pipe(
  IOO.of('fp-ts'),
  IOO.tapIO(value => Console.log(`Hello, ${value}`)),
)

// No output to the stdout
const effectB = pipe(
  IOO.none as IOO.IOOption<string>,
  IOO.tapIO(value => Console.log(`Hello, ${value}`)),
)

async function test() {
  assert.deepStrictEqual(effectA(), O.of('fp-ts'))
  assert.deepStrictEqual(effectB(), O.none)
}

test()

License​

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

Constructors​

none​

Signature​

export declare const none: IOOption<never>

Details​

  • Added in 0.1.0

License​

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

of​

Signature​

export declare const of: <A>(a: A) => IOOption<A>

Details​

  • Added in 0.1.0

License​

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

some​

Signature​

export declare const some: <A>(a: A) => IOOption<A>

Details​

  • Added in 0.1.0

License​

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

Conversions​

fromEither​

Signature​

export declare const fromEither: <A>(fa: Either<unknown, A>) => IOOption<A>

Details​

  • Added in 0.1.0

License​

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

fromIO​

Signature​

export declare const fromIO: <A>(fa: IO<A>) => IOOption<A>

Details​

  • Added in 0.1.0

License​

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

fromIOEither​

Signature​

export declare const fromIOEither: <A>(fa: IOEither<unknown, A>) => IOOption<A>

Details​

  • Added in 0.1.0

License​

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

fromNullable​

Signature​

export declare const fromNullable: <A>(a: A) => IOOption<NonNullable<A>>

Details​

  • Added in 0.1.0

License​

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

fromOption​

Signature​

export declare const fromOption: <A>(fa: Option<A>) => IOOption<A>

Details​

  • Added in 0.1.0

License​

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

toNullable​

Signature​

export declare const toNullable: <A>(ma: IOOption<A>) => IO<A | null>

Details​

  • Added in 0.1.0

License​

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

toUndefined​

Signature​

export declare const toUndefined: <A>(ma: IOOption<A>) => IO<A | undefined>

Details​

  • Added in 0.1.0

License​

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

Do notation​

Do​

Signature​

export declare const Do: IOOption<{}>

Details​

  • Added in 0.1.0

License​

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

apS​

Signature​

export declare const apS: <N extends string, A, B>(
  name: Exclude<N, keyof A>,
  fb: IOOption<B>,
) => (fa: IOOption<A>) => IOOption<{ 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

bind​

Signature​

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

Details​

  • Added in 0.1.0

License​

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

guard​

Signature​

export declare const guard: (b: boolean) => IOOption<void>

Details​

  • Added in 0.1.0

License​

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

Error handling​

alt​

Signature​

export declare const alt: <A>(second: LazyArg<IOOption<A>>) => (first: IOOption<A>) => IOOption<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 return types will be merged.

Signature​

export declare const altW: <B>(second: LazyArg<IOOption<B>>) => <A>(first: IOOption<A>) => IOOption<A | B>

Details​

  • Added in 0.1.0

License​

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

getOrElse​

Signature​

export declare const getOrElse: <A>(onNone: LazyArg<IO<A>>) => (fa: IOOption<A>) => IO<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: <B>(onNone: LazyArg<IO<B>>) => <A>(ma: IOOption<A>) => IO<A | B>

Details​

  • Added in 0.1.0

License​

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

Filtering​

compact​

Signature​

export declare const compact: Compactable1<URI>['compact']

Details​

  • Added in 0.1.0

License​

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

filter​

Signature​

export declare const filter: {
  <A, B extends A>(refinement: Refinement<A, B>): (fb: IOOption<A>) => IOOption<B>
  <A>(predicate: Predicate<A>): <B extends A>(fb: IOOption<B>) => IOOption<B>
  <A>(predicate: Predicate<A>): (fa: IOOption<A>) => IOOption<A>
}

Details​

  • Added in 0.1.0

License​

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

filterMap​

Signature​

export declare const filterMap: <A, B>(f: (a: A) => Option<B>) => (fga: IOOption<A>) => IOOption<B>

Details​

  • Added in 0.1.0

License​

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

partition​

Signature​

export declare const partition: {
  <A, B extends A>(refinement: Refinement<A, B>): (fb: IOOption<A>) => Separated<IOOption<A>, IOOption<B>>
  <A>(predicate: Predicate<A>): <B extends A>(fb: IOOption<B>) => Separated<IOOption<B>, IOOption<B>>
  <A>(predicate: Predicate<A>): (fa: IOOption<A>) => Separated<IOOption<A>, IOOption<A>>
}

Details​

  • Added in 0.1.0

License​

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

partitionMap​

Signature​

export declare const partitionMap: <A, B, C>(
  f: (a: A) => Either<B, C>,
) => (fa: IOOption<A>) => Separated<IOOption<B>, IOOption<C>>

Details​

  • Added in 0.1.0

License​

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

separate​

Signature​

export declare const separate: Compactable1<URI>['separate']

Details​

  • Added in 0.1.0

License​

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

Instance methods​

chainRec​

Signature​

export declare const chainRec: ChainRec1<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, B>(f: (a: A) => IOOption<B>) => (ma: IOOption<A>) => IOOption<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) => Either<E, B>) => (ma: IOOption<A>) => IOOption<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, B>(f: (a: A) => IOOption<B>) => (first: IOOption<A>) => IOOption<A>

Details​

  • Added in 0.1.0

License​

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

chainFirstEitherK​

Alias of tapEither.

Signature​

export declare const chainFirstEitherK: <E, A, B>(f: (a: A) => Either<E, B>) => (ma: IOOption<A>) => IOOption<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>) => (first: IOOption<A>) => IOOption<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>) => (first: IOOption<A>) => IOOption<B>

Details​

  • Added in 0.1.0

License​

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

chainNullableK​

Alias of flatMapNullable.

Signature​

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

Details​

  • Added in 0.1.0

License​

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

chainOptionK​

Alias of flatMapOption.

Signature​

export declare const chainOptionK: <A, B>(f: (a: A) => Option<B>) => (ma: IOOption<A>) => IOOption<B>

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) => Either<E, B>,
) => (...a: A) => IOOption<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) => I.IO<B>) => (...a: A) => IOOption<B>

Details​

  • Added in 0.1.0

License​

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

fromNullableK​

Signature​

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

Details​

  • Added in 0.1.0

License​

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

fromOptionK​

Signature​

export declare const fromOptionK: <A extends ReadonlyArray<unknown>, B>(
  f: (...a: A) => Option<B>,
) => (...a: A) => IOOption<B>

Details​

  • Added in 0.1.0

License​

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

fromPredicate​

Signature​

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

Details​

  • Added in 0.1.0

License​

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

Mapping​

as​

Maps the Some value of this IOOption to the specified constant value.

Signature​

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

Details​

  • Added in 0.1.0

License​

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

asUnit​

Maps the Some value of this IOOption to the void constant value.

Signature​

export declare const asUnit: <_>(self: IOOption<_>) => IOOption<void>

Details​

  • Added in 0.1.0

License​

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

flap​

Signature​

export declare const flap: <A>(a: A) => <B>(fab: IOOption<(a: A) => B>) => IOOption<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) => (fa: IOOption<A>) => IOOption<B>

Details​

  • Added in 0.1.0

License​

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

Model​

IOOption​

Signature​

export interface IOOption<A> extends IO<Option<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: <B, A>(onNone: () => I.IO<B>, onSome: (a: A) => I.IO<B>) => (ma: IOOption<A>) => I.IO<B>

Details​

  • Added in 0.1.0

License​

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

match​

Signature​

export declare const match: <B, A>(onNone: () => B, onSome: (a: A) => B) => (ma: IOOption<A>) => IO<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 (IO).

Signature​

export declare const matchE: <B, A>(onNone: () => IO<B>, onSome: (a: A) => IO<B>) => (ma: IOOption<A>) => IO<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: <B, C, A>(onNone: () => IO<B>, onSome: (a: A) => IO<C>) => (ma: IOOption<A>) => IO<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: <B, A, C>(onNone: () => B, onSome: (a: A) => C) => (ma: IOOption<A>) => IO<B | C>

Details​

  • Added in 0.1.0

License​

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

Sequencing​

flatMap​

Signature​

export declare const flatMap: {
  <A, B>(f: (a: A) => IOOption<B>): (ma: IOOption<A>) => IOOption<B>
  <A, B>(ma: IOOption<A>, f: (a: A) => IOOption<B>): IOOption<B>
}

Details​

  • Added in 0.1.0

License​

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

flatMapEither​

Signature​

export declare const flatMapEither: {
  <A, B, _>(f: (a: A) => Either<_, B>): (self: IOOption<A>) => IOOption<B>
  <A, B, _>(self: IOOption<A>, f: (a: A) => Either<_, B>): IOOption<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>): (self: IOOption<A>) => IOOption<B>
  <A, B>(self: IOOption<A>, f: (a: A) => IO<B>): IOOption<B>
}

Details​

  • Added in 0.1.0

License​

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

flatMapNullable​

Signature​

export declare const flatMapNullable: {
  <A, B>(f: (a: A) => B | null | undefined): (self: IOOption<A>) => IOOption<B>
  <A, B>(self: IOOption<A>, f: (a: A) => B | null | undefined): IOOption<B>
}

Details​

  • Added in 0.1.0

License​

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

flatMapOption​

Signature​

export declare const flatMapOption: {
  <A, B>(f: (a: A) => Option<B>): (self: IOOption<A>) => IOOption<B>
  <A, B>(self: IOOption<A>, f: (a: A) => Option<B>): IOOption<B>
}

Details​

  • Added in 0.1.0

License​

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

flatten​

Signature​

export declare const flatten: <A>(mma: IOOption<IOOption<A>>) => IOOption<A>

Details​

  • Added in 0.1.0

License​

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

Traversing​

traverseReadonlyArrayWithIndex​

Equivalent to ReadonlyArray#traverseWithIndex(Applicative).

Signature​

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

Details​

  • Added in 0.1.0

License​

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

Utilities​

ApT​

Signature​

export declare const ApT: IOOption<readonly []>

Details​

  • Added in 0.1.0

License​

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

ap​

Signature​

export declare const ap: <A>(fa: IOOption<A>) => <B>(fab: IOOption<(a: A) => B>) => IOOption<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: <B>(second: IOOption<B>) => <A>(first: IOOption<A>) => IOOption<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: <B>(second: IOOption<B>) => <A>(first: IOOption<A>) => IOOption<B>

Details​

  • Added in 0.1.0

License​

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

do​

Signature​

export declare const do_: <MA extends IOOptionIterable<any>, A>(
  yieldFunction: (unwrap: <A>(ma: IOOption<A>) => IOOptionIterable<A>) => Generator<MA, A>,
) => IOOption<A>

let​

Signature​

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

throwError​

Signature​

export declare const throwError: MonadThrow1<URI>['throwError']

Details​

  • Added in 0.1.0

License​

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

zero​

Signature​

export declare const zero: <A>() => IOOption<A>

Details​

  • Added in 0.1.0

License​

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