/**
 * @since 0.0.1
 */
import type { Alt2 } from 'fp-ts/Alt'
import type { Alternative2 } from 'fp-ts/Alternative'
import type { Applicative2 } from 'fp-ts/Applicative'
import type { Apply2 } from 'fp-ts/Apply'
import type { Compactable2, Separated } from 'fp-ts/Compactable'
import type { Either } from 'fp-ts/Either'
import type { Filterable2 } from 'fp-ts/Filterable'
import type { Functor2 } from 'fp-ts/Functor'
import type { Monad2 } from 'fp-ts/Monad'
import type { Option } from 'fp-ts/Option'
import type { Reader } from 'fp-ts/Reader'
import { Lazy, Predicate, Refinement } from 'fp-ts/function'
/**
 * @category model
 * @since 0.0.1
 */
export interface ReaderOption<R, A> {
  (r: R): Option<A>
}
/**
 * @category constructors
 * @since 0.0.1
 */
export declare const none: ReaderOption<any, never>
/**
 * @category constructors
 * @since 0.0.1
 */
export declare const some: <R, A>(a: A) => ReaderOption<R, A>
/**
 * @category constructors
 * @since 0.0.1
 */
export declare const ask: <R>() => ReaderOption<R, R>
/**
 * @category constructors
 * @since 0.0.1
 */
export declare const asks: <R, A>(f: (r: R) => A) => ReaderOption<R, A>
/**
 * @category constructors
 * @since 0.0.1
 */
export declare const fromOption: <R, A>(ma: Option<A>) => ReaderOption<R, A>
/**
 * @category constructors
 * @since 0.0.1
 */
export declare const fromReader: <R, A>(ma: Reader<R, A>) => ReaderOption<R, A>
/**
 * @category constructors
 * @since 0.0.1
 */
export declare const fromPredicate: {
  <A, B extends A>(refinement: Refinement<A, B>): <U>(a: A) => ReaderOption<U, B>
  <A>(predicate: Predicate<A>): <R>(a: A) => ReaderOption<R, A>
}
/**
 * @category destructors
 * @since 0.0.1
 */
export declare const fold: <R, A, B>(
  onNone: Lazy<Reader<R, B>>,
  onSome: (a: A) => Reader<R, B>
) => (ma: ReaderOption<R, A>) => Reader<R, B>
/**
 * @category destructors
 * @since 0.0.1
 */
export declare const getOrElseW: <R, B>(
  onNone: Lazy<Reader<R, B>>
) => <Q, A>(ma: ReaderOption<Q, A>) => Reader<Q & R, B | A>
/**
 * @category destructors
 * @since 0.0.1
 */
export declare const getOrElse: <R, A>(
  onNone: Lazy<Reader<R, A>>
) => (ma: ReaderOption<R, A>) => Reader<R, A>
/**
 * @category combinators
 * @since 0.0.1
 */
export declare const fromOptionK: <A extends ReadonlyArray<unknown>, B>(
  f: (...a: A) => Option<B>
) => <R>(...a: A) => ReaderOption<R, B>
/**
 * @category combinators
 * @since 0.0.1
 */
export declare const chainOptionK: <A, B>(
  f: (a: A) => Option<B>
) => <R>(ma: ReaderOption<R, A>) => ReaderOption<R, B>
/**
 * @category Functor
 * @since 0.0.1
 */
export declare const map: <A, B>(
  f: (a: A) => B
) => <R>(fa: ReaderOption<R, A>) => ReaderOption<R, B>
/**
 * @category Apply
 * @since 0.0.1
 */
export declare const ap: <R, A>(
  fa: ReaderOption<R, A>
) => <B>(fab: ReaderOption<R, (a: A) => B>) => ReaderOption<R, B>
/**
 * @category Apply
 * @since 0.0.1
 */
export declare const apFirst: <R, B>(
  fb: ReaderOption<R, B>
) => <A>(fa: ReaderOption<R, A>) => ReaderOption<R, A>
/**
 * @category Apply
 * @since 0.0.1
 */
export declare const apSecond: <R, B>(
  fb: ReaderOption<R, B>
) => <A>(fa: ReaderOption<R, A>) => ReaderOption<R, B>
/**
 * @category Monad
 * @since 0.0.1
 */
export declare const chain: <R, A, B>(
  f: (a: A) => ReaderOption<R, B>
) => (ma: ReaderOption<R, A>) => ReaderOption<R, B>
/**
 * @category Applicative
 * @since 0.0.1
 */
export declare const of: Applicative2<URI>['of']
/**
 * @category Monad
 * @since 0.0.1
 */
export declare const chainFirst: <R, A, B>(
  f: (a: A) => ReaderOption<R, B>
) => (ma: ReaderOption<R, A>) => ReaderOption<R, A>
/**
 * @category Monad
 * @since 0.0.1
 */
export declare const flatten: <R, A>(mma: ReaderOption<R, ReaderOption<R, A>>) => ReaderOption<R, A>
/**
 * @category Alternative
 * @since 0.0.1
 */
export declare const alt: <R, A>(
  that: Lazy<ReaderOption<R, A>>
) => (fa: ReaderOption<R, A>) => ReaderOption<R, A>
/**
 * @category Alternative
 * @since 0.0.1
 */
export declare const zero: Alternative2<URI>['zero']
/**
 * @category Compactable
 * @since 0.0.1
 */
export declare const compact: <R, A>(fa: ReaderOption<R, Option<A>>) => ReaderOption<R, A>
/**
 * @category Compactable
 * @since 0.0.1
 */
export declare const separate: <R, A, B>(
  ma: ReaderOption<R, Either<A, B>>
) => Separated<ReaderOption<R, A>, ReaderOption<R, B>>
/**
 * @category Filterable
 * @since 0.0.1
 */
export declare const filter: {
  <A, B extends A>(refinement: Refinement<A, B>): <R>(fa: ReaderOption<R, A>) => ReaderOption<R, B>
  <A>(predicate: Predicate<A>): <R>(fa: ReaderOption<R, A>) => ReaderOption<R, A>
}
/**
 * @category Filterable
 * @since 0.0.1
 */
export declare const filterMap: <R, A, B>(
  f: (a: A) => Option<B>
) => (fa: ReaderOption<R, A>) => ReaderOption<R, B>
/**
 * @category Filterable
 * @since 0.0.1
 */
export declare const partition: {
  <A, B extends A>(refinement: Refinement<A, B>): <R>(
    fa: ReaderOption<R, A>
  ) => Separated<ReaderOption<R, A>, ReaderOption<R, B>>
  <A>(predicate: Predicate<A>): <R>(
    fa: ReaderOption<R, A>
  ) => Separated<ReaderOption<R, A>, ReaderOption<R, A>>
}
/**
 * @category Filterable
 * @since 0.0.1
 */
export declare const partitionMap: <A, B, C>(
  f: (a: A) => Either<B, C>
) => <R>(fa: ReaderOption<R, A>) => Separated<ReaderOption<R, B>, ReaderOption<R, C>>
/**
 * @category instances
 * @since 0.0.1
 */
export declare const URI = 'ReaderOption'
/**
 * @category instances
 * @since 0.0.1
 */
export declare type URI = typeof URI
declare module 'fp-ts/HKT' {
  interface URItoKind2<E, A> {
    readonly [URI]: ReaderOption<E, A>
  }
}
/**
 * @category instances
 * @since 0.0.1
 */
export declare const Functor: Functor2<URI>
/**
 * @category instances
 * @since 0.0.1
 */
export declare const Apply: Apply2<URI>
/**
 * @category instances
 * @since 0.0.1
 */
export declare const Applicative: Applicative2<URI>
/**
 * @category instances
 * @since 0.0.1
 */
export declare const Monad: Monad2<URI>
/**
 * @category instances
 * @since 0.0.1
 */
export declare const Alt: Alt2<URI>
/**
 * @category instances
 * @since 0.0.1
 */
export declare const Alternative: Alternative2<URI>
/**
 * @category instances
 * @since 0.0.1
 */
export declare const Compactable: Compactable2<URI>
/**
 * @category instances
 * @since 0.0.1
 */
export declare const Filterable: Filterable2<URI>
/**
 * @category do notation
 * @since 0.0.1
 */
export declare const bindTo: <N extends string>(
  name: N
) => <R, A>(fa: ReaderOption<R, A>) => ReaderOption<R, { [K in N]: A }>
/**
 * @category do notation
 * @since 0.0.1
 */
export declare const bind: <N extends string, R, A, B>(
  name: Exclude<N, keyof A>,
  f: (a: A) => ReaderOption<R, B>
) => (
  fa: ReaderOption<R, A>
) => ReaderOption<R, { [K in N | keyof A]: K extends keyof A ? A[K] : B }>