export declare const alt: <A>(that: () => IOOption<A>) => (fa: IOOption<A>) => IOOption<A>

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

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

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

export declare const apFirst: <B>(fb: IOOption<B>) => <A>(fa: IOOption<A>) => IOOption<A>

export declare const apSecond: <B>(fb: IOOption<B>) => <A>(fa: IOOption<A>) => IOOption<B>

export declare const compact: <A>(fa: IOOption<O.Option<A>>) => IOOption<A>

export declare const separate: <A, B>(fa: IOOption<Either<A, B>>) => Separated<IOOption<A>, IOOption<B>>

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

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

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

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

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

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

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

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

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

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

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

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

export declare const fromIO: <A = never>(ma: IO<A>) => IOOption<A>

export declare const fromIOEither: <A>(ma: IOEither<any, A>) => IOOption<A>

export declare const fromIOK: <A extends unknown[], B>(f: (...a: A) => IO<B>) => (...a: A) => IOOption<B>

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

export declare const fromOption: <A = never>(ma: O.Option<A>) => IOOption<A>

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

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>
}

export declare const none: IOOption<never>

export declare const some: <A = never>(a: A) => IOOption<A>

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

export declare const getOrElse: <A>(onNone: () => IO<A>) => (ma: IOOption<A>) => IO<A>

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

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

export declare const Alt: Alt1<'IOOption'>

export declare const Alternative: Alternative1<'IOOption'>

export declare const Applicative: Applicative1<'IOOption'>

export declare const Apply: Apply1<'IOOption'>

export declare const Compactable: Compactable1<'IOOption'>

export declare const Filterable: Filterable1<'IOOption'>

export declare const Functor: Functor1<'IOOption'>

export declare const Monad: Monad1<'IOOption'>

export declare const URI: 'IOOption'

export type URI = typeof URI

export declare const getApplyMonoid: <A>(M: Monoid<A>) => Monoid<IOOption<A>>

export declare const getApplySemigroup: <A>(S: Semigroup<A>) => Semigroup<IOOption<A>>

export interface IOOption<A> extends IO<Option<A>> {}

export declare const ioOption: Monad1<'IOOption'> & Alt1<'IOOption'> & MonadIO1<'IOOption'> & Filterable1<'IOOption'>