603 lines
16 KiB
TypeScript
603 lines
16 KiB
TypeScript
/**
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* `IOOption<A>` represents a synchronous computation that either yields a value of type `A` or nothing.
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*
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* If you want to represent a synchronous computation that never fails, please see `IO`.
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* If you want to represent a synchronous computation that may fail, please see `IOEither`.
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*
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* @since 2.12.0
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*/
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import { Alt1 } from './Alt'
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import { Alternative1 } from './Alternative'
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import { Applicative1 } from './Applicative'
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import { Apply1 } from './Apply'
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import * as chainable from './Chain'
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import { Compactable1 } from './Compactable'
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import { Either } from './Either'
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import { Filterable1 } from './Filterable'
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import { FromEither1 } from './FromEither'
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import { FromIO1 } from './FromIO'
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import { LazyArg } from './function'
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import { Functor1 } from './Functor'
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import * as I from './IO'
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import { IOEither } from './IOEither'
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import { Monad1 } from './Monad'
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import { MonadIO1 } from './MonadIO'
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import * as O from './Option'
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import { Pointed1 } from './Pointed'
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import { Predicate } from './Predicate'
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import { ReadonlyNonEmptyArray } from './ReadonlyNonEmptyArray'
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import { Refinement } from './Refinement'
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import { Separated } from './Separated'
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import { Zero1 } from './Zero'
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import IO = I.IO
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import Option = O.Option
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/**
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* @category model
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* @since 2.12.0
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*/
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export interface IOOption<A> extends IO<Option<A>> {}
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/**
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* @category constructors
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* @since 2.12.0
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*/
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export declare const some: <A>(a: A) => IOOption<A>
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/**
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* @category lifting
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* @since 2.12.0
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*/
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export declare const fromPredicate: {
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<A, B extends A>(refinement: Refinement<A, B>): (a: A) => IOOption<B>
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<A>(predicate: Predicate<A>): <B extends A>(b: B) => IOOption<B>
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<A>(predicate: Predicate<A>): (a: A) => IOOption<A>
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}
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/**
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* @category conversions
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* @since 2.12.0
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*/
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export declare const fromOption: <A>(fa: Option<A>) => IOOption<A>
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/**
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* @category conversions
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* @since 2.12.0
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*/
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export declare const fromEither: <A>(fa: Either<unknown, A>) => IOOption<A>
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/**
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* @category conversions
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* @since 2.12.0
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*/
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export declare const fromIO: <A>(fa: IO<A>) => IOOption<A>
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/**
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* @category conversions
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* @since 2.12.0
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*/
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export declare const fromIOEither: <A>(fa: IOEither<unknown, A>) => IOOption<A>
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/**
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* @category pattern matching
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* @since 2.12.0
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*/
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export declare const match: <B, A>(onNone: () => B, onSome: (a: A) => B) => (ma: IOOption<A>) => IO<B>
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/**
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* Less strict version of [`match`](#match).
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*
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* The `W` suffix (short for **W**idening) means that the handler return types will be merged.
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*
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* @category pattern matching
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* @since 2.12.0
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*/
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export declare const matchW: <B, A, C>(onNone: () => B, onSome: (a: A) => C) => (ma: IOOption<A>) => IO<B | C>
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/**
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* The `E` suffix (short for **E**ffect) means that the handlers return an effect (`IO`).
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*
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* @category pattern matching
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* @since 2.12.0
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*/
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export declare const matchE: <B, A>(onNone: () => IO<B>, onSome: (a: A) => IO<B>) => (ma: IOOption<A>) => IO<B>
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/**
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* Alias of [`matchE`](#matche).
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*
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* @category pattern matching
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* @since 2.12.0
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*/
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export declare const fold: <B, A>(onNone: () => I.IO<B>, onSome: (a: A) => I.IO<B>) => (ma: IOOption<A>) => I.IO<B>
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/**
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* Less strict version of [`matchE`](#matche).
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*
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* The `W` suffix (short for **W**idening) means that the handler return types will be merged.
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*
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* @category pattern matching
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* @since 2.12.0
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*/
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export declare const matchEW: <B, C, A>(onNone: () => IO<B>, onSome: (a: A) => IO<C>) => (ma: IOOption<A>) => IO<B | C>
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/**
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* @category error handling
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* @since 2.12.0
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*/
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export declare const getOrElse: <A>(onNone: LazyArg<IO<A>>) => (fa: IOOption<A>) => IO<A>
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/**
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* Less strict version of [`getOrElse`](#getorelse).
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*
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* The `W` suffix (short for **W**idening) means that the handler return type will be merged.
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*
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* @category error handling
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* @since 2.12.0
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*/
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export declare const getOrElseW: <B>(onNone: LazyArg<IO<B>>) => <A>(ma: IOOption<A>) => IO<A | B>
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/**
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* @category conversions
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* @since 2.12.0
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*/
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export declare const toUndefined: <A>(ma: IOOption<A>) => IO<A | undefined>
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/**
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* @category conversions
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* @since 2.12.0
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*/
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export declare const toNullable: <A>(ma: IOOption<A>) => IO<A | null>
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/**
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* @category conversions
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* @since 2.12.0
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*/
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export declare const fromNullable: <A>(a: A) => IOOption<NonNullable<A>>
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/**
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* @category lifting
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* @since 2.12.0
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*/
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export declare const fromNullableK: <A extends ReadonlyArray<unknown>, B>(
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f: (...a: A) => B | null | undefined
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) => (...a: A) => IOOption<NonNullable<B>>
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/**
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* Alias of `flatMapNullable`.
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*
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* @category legacy
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* @since 2.12.0
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*/
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export declare const chainNullableK: <A, B>(
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f: (a: A) => B | null | undefined
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) => (ma: IOOption<A>) => IOOption<NonNullable<B>>
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/**
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* @category lifting
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* @since 2.12.0
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*/
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export declare const fromOptionK: <A extends ReadonlyArray<unknown>, B>(
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f: (...a: A) => Option<B>
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) => (...a: A) => IOOption<B>
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/**
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* `map` can be used to turn functions `(a: A) => B` into functions `(fa: F<A>) => F<B>` whose argument and return types
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* use the type constructor `F` to represent some computational context.
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*
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* @category mapping
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* @since 2.12.0
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*/
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export declare const map: <A, B>(f: (a: A) => B) => (fa: IOOption<A>) => IOOption<B>
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/**
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* @since 2.12.0
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*/
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export declare const ap: <A>(fa: IOOption<A>) => <B>(fab: IOOption<(a: A) => B>) => IOOption<B>
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/**
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* @category constructors
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* @since 2.12.0
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*/
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export declare const of: <A>(a: A) => IOOption<A>
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/**
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* @category sequencing
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* @since 2.14.0
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*/
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export declare const flatMap: {
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<A, B>(f: (a: A) => IOOption<B>): (ma: IOOption<A>) => IOOption<B>
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<A, B>(ma: IOOption<A>, f: (a: A) => IOOption<B>): IOOption<B>
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}
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/**
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* @category sequencing
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* @since 2.12.0
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*/
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export declare const flatten: <A>(mma: IOOption<IOOption<A>>) => IOOption<A>
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/**
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* @category error handling
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* @since 2.12.0
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*/
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export declare const alt: <A>(second: LazyArg<IOOption<A>>) => (first: IOOption<A>) => IOOption<A>
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/**
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* Less strict version of [`alt`](#alt).
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*
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* The `W` suffix (short for **W**idening) means that the return types will be merged.
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*
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* @category error handling
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* @since 2.12.0
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*/
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export declare const altW: <B>(second: LazyArg<IOOption<B>>) => <A>(first: IOOption<A>) => IOOption<A | B>
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/**
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* @since 2.12.0
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*/
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export declare const zero: <A>() => IOOption<A>
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/**
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* @category constructors
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* @since 2.12.0
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*/
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export declare const none: IOOption<never>
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/**
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* @category filtering
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* @since 2.12.0
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*/
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export declare const compact: Compactable1<URI>['compact']
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/**
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* @category filtering
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* @since 2.12.0
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*/
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export declare const separate: Compactable1<URI>['separate']
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/**
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* @category filtering
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* @since 2.12.0
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*/
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export declare const filter: {
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<A, B extends A>(refinement: Refinement<A, B>): (fb: IOOption<A>) => IOOption<B>
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<A>(predicate: Predicate<A>): <B extends A>(fb: IOOption<B>) => IOOption<B>
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<A>(predicate: Predicate<A>): (fa: IOOption<A>) => IOOption<A>
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}
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/**
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* @category filtering
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* @since 2.12.0
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*/
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export declare const filterMap: <A, B>(f: (a: A) => Option<B>) => (fga: IOOption<A>) => IOOption<B>
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/**
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* @category filtering
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* @since 2.12.0
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*/
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export declare const partition: {
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<A, B extends A>(refinement: Refinement<A, B>): (fb: IOOption<A>) => Separated<IOOption<A>, IOOption<B>>
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<A>(predicate: Predicate<A>): <B extends A>(fb: IOOption<B>) => Separated<IOOption<B>, IOOption<B>>
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<A>(predicate: Predicate<A>): (fa: IOOption<A>) => Separated<IOOption<A>, IOOption<A>>
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}
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/**
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* @category filtering
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* @since 2.12.0
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*/
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export declare const partitionMap: <A, B, C>(
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f: (a: A) => Either<B, C>
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) => (fa: IOOption<A>) => Separated<IOOption<B>, IOOption<C>>
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/**
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* @category type lambdas
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* @since 2.12.0
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*/
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export declare const URI = 'IOOption'
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/**
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* @category type lambdas
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* @since 2.12.0
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*/
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export type URI = typeof URI
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declare module './HKT' {
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interface URItoKind<A> {
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readonly [URI]: IOOption<A>
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}
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}
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Functor: Functor1<URI>
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/**
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* Maps the `Some` value of this `IOOption` to the specified constant value.
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*
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* @category mapping
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* @since 2.16.0
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*/
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export declare const as: {
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<A>(a: A): <_>(self: IOOption<_>) => IOOption<A>
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<_, A>(self: IOOption<_>, a: A): IOOption<A>
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}
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/**
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* Maps the `Some` value of this `IOOption` to the void constant value.
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*
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* @category mapping
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* @since 2.16.0
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*/
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export declare const asUnit: <_>(self: IOOption<_>) => IOOption<void>
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/**
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* @category mapping
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* @since 2.12.0
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*/
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export declare const flap: <A>(a: A) => <B>(fab: IOOption<(a: A) => B>) => IOOption<B>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Pointed: Pointed1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Apply: Apply1<URI>
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/**
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* Combine two effectful actions, keeping only the result of the first.
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*
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* @since 2.12.0
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*/
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export declare const apFirst: <B>(second: IOOption<B>) => <A>(first: IOOption<A>) => IOOption<A>
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/**
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* Combine two effectful actions, keeping only the result of the second.
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*
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* @since 2.12.0
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*/
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export declare const apSecond: <B>(second: IOOption<B>) => <A>(first: IOOption<A>) => IOOption<B>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Applicative: Applicative1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Chain: chainable.Chain1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const FromEither: FromEither1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const FromIO: FromIO1<URI>
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/**
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* Composes computations in sequence, using the return value of one computation to determine the next computation and
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* keeping only the result of the first.
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*
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* @category combinators
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* @since 2.15.0
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*/
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export declare const tap: {
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<A, _>(self: IOOption<A>, f: (a: A) => IOOption<_>): IOOption<A>
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<A, _>(f: (a: A) => IOOption<_>): (self: IOOption<A>) => IOOption<A>
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}
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/**
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* Composes computations in sequence, using the return value of one computation to determine the next computation and
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* keeping only the result of the first.
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*
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* @example
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* import { pipe } from 'fp-ts/function'
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* import * as IOO from 'fp-ts/IOOption'
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* import * as O from 'fp-ts/Option'
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* import * as E from 'fp-ts/Either'
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*
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* const compute = (value: number) => pipe(
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* IOO.of(value),
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* IOO.tapEither((value) => value > 0 ? E.right('ok') : E.left('error')),
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* )
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*
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* assert.deepStrictEqual(compute(1)(), O.of(1))
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* assert.deepStrictEqual(compute(-1)(), O.none)
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*
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* @category combinators
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* @since 2.16.0
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*/
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export declare const tapEither: {
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<A, E, _>(f: (a: A) => Either<E, _>): (self: IOOption<A>) => IOOption<A>
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<A, E, _>(self: IOOption<A>, f: (a: A) => Either<E, _>): IOOption<A>
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}
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/**
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* Composes computations in sequence, using the return value of one computation to determine the next computation and
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* keeping only the result of the first.
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*
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* @example
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* import { pipe } from 'fp-ts/function'
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* import * as IOO from 'fp-ts/IOOption'
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* import * as O from 'fp-ts/Option'
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* import * as Console from 'fp-ts/Console'
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*
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* // Will produce `Hello, fp-ts` to the stdout
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* const effectA = pipe(
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* IOO.of('fp-ts'),
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* IOO.tapIO((value) => Console.log(`Hello, ${value}`)),
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* )
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*
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* // No output to the stdout
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* const effectB = pipe(
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* IOO.none as IOO.IOOption<string>,
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* IOO.tapIO((value) => Console.log(`Hello, ${value}`)),
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* )
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*
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* async function test() {
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* assert.deepStrictEqual(effectA(), O.of('fp-ts'))
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* assert.deepStrictEqual(effectB(), O.none)
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* }
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*
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* test()
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*
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* @category combinators
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* @since 2.16.0
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*/
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export declare const tapIO: {
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<A, _>(f: (a: A) => IO<_>): (self: IOOption<A>) => IOOption<A>
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<A, _>(self: IOOption<A>, f: (a: A) => IO<_>): IOOption<A>
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}
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Alt: Alt1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Zero: Zero1<URI>
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/**
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* @category do notation
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* @since 2.12.0
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*/
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export declare const guard: (b: boolean) => IOOption<void>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Alternative: Alternative1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Monad: Monad1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const MonadIO: MonadIO1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Compactable: Compactable1<URI>
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/**
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* @category instances
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* @since 2.12.0
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*/
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export declare const Filterable: Filterable1<URI>
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/**
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* @category sequencing
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* @since 2.16.0
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*/
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export declare const flatMapIO: {
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<A, B>(f: (a: A) => IO<B>): (self: IOOption<A>) => IOOption<B>
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<A, B>(self: IOOption<A>, f: (a: A) => IO<B>): IOOption<B>
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}
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/**
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* @category sequencing
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* @since 2.16.0
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*/
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export declare const flatMapOption: {
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<A, B>(f: (a: A) => Option<B>): (self: IOOption<A>) => IOOption<B>
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<A, B>(self: IOOption<A>, f: (a: A) => Option<B>): IOOption<B>
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}
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/**
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* @category sequencing
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* @since 2.16.0
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*/
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export declare const flatMapEither: {
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<A, B, _>(f: (a: A) => Either<_, B>): (self: IOOption<A>) => IOOption<B>
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<A, B, _>(self: IOOption<A>, f: (a: A) => Either<_, B>): IOOption<B>
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}
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/**
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* @category sequencing
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* @since 2.16.0
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*/
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export declare const flatMapNullable: {
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<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>
|
|
}
|
|
/**
|
|
* @category lifting
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const fromIOK: <A extends ReadonlyArray<unknown>, B>(f: (...a: A) => I.IO<B>) => (...a: A) => IOOption<B>
|
|
/**
|
|
* Alias of `flatMapIO`.
|
|
*
|
|
* @category legacy
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const chainIOK: <A, B>(f: (a: A) => I.IO<B>) => (first: IOOption<A>) => IOOption<B>
|
|
/**
|
|
* Alias of `tapIO`.
|
|
*
|
|
* @category legacy
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const chainFirstIOK: <A, B>(f: (a: A) => I.IO<B>) => (first: IOOption<A>) => IOOption<A>
|
|
/**
|
|
* @category lifting
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const fromEitherK: <E, A extends ReadonlyArray<unknown>, B>(
|
|
f: (...a: A) => Either<E, B>
|
|
) => (...a: A) => IOOption<B>
|
|
/**
|
|
* Alias of `flatMapEither`.
|
|
*
|
|
* @category legacy
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const chainEitherK: <E, A, B>(f: (a: A) => Either<E, B>) => (ma: IOOption<A>) => IOOption<B>
|
|
/**
|
|
* Alias of `tapEither`.
|
|
*
|
|
* @category legacy
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const chainFirstEitherK: <E, A, B>(f: (a: A) => Either<E, B>) => (ma: IOOption<A>) => IOOption<A>
|
|
/**
|
|
* Alias of `flatMapOption`.
|
|
*
|
|
* @category legacy
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const chainOptionK: <A, B>(f: (a: A) => Option<B>) => (ma: IOOption<A>) => IOOption<B>
|
|
/**
|
|
* @category do notation
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const Do: IOOption<{}>
|
|
/**
|
|
* @category do notation
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const bindTo: <N extends string>(name: N) => <A>(fa: IOOption<A>) => IOOption<{ readonly [K in N]: A }>
|
|
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 }>
|
|
export {
|
|
/**
|
|
* @category do notation
|
|
* @since 2.13.0
|
|
*/
|
|
let_ as let
|
|
}
|
|
/**
|
|
* @category do notation
|
|
* @since 2.12.0
|
|
*/
|
|
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 }>
|
|
/**
|
|
* @category do notation
|
|
* @since 2.12.0
|
|
*/
|
|
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 }>
|
|
/**
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const ApT: IOOption<readonly []>
|
|
/**
|
|
* Equivalent to `ReadonlyNonEmptyArray#traverseWithIndex(Applicative)`.
|
|
*
|
|
* @category traversing
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const traverseReadonlyNonEmptyArrayWithIndex: <A, B>(
|
|
f: (index: number, a: A) => IOOption<B>
|
|
) => (as: ReadonlyNonEmptyArray<A>) => IOOption<ReadonlyNonEmptyArray<B>>
|
|
/**
|
|
* Equivalent to `ReadonlyArray#traverseWithIndex(Applicative)`.
|
|
*
|
|
* @category traversing
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const traverseReadonlyArrayWithIndex: <A, B>(
|
|
f: (index: number, a: A) => IOOption<B>
|
|
) => (as: readonly A[]) => IOOption<readonly B[]>
|
|
/**
|
|
* Alias of `flatMap`.
|
|
*
|
|
* @category legacy
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const chain: <A, B>(f: (a: A) => IOOption<B>) => (ma: IOOption<A>) => IOOption<B>
|
|
/**
|
|
* Alias of `tap`.
|
|
*
|
|
* @category legacy
|
|
* @since 2.12.0
|
|
*/
|
|
export declare const chainFirst: <A, B>(f: (a: A) => IOOption<B>) => (first: IOOption<A>) => IOOption<A>
|