/**
 * @since 2.0.0
 */
import { Alt3, Alt3C } from './Alt.js';
import { Applicative3, Applicative3C } from './Applicative.js';
import { Apply3 } from './Apply.js';
import { Bifunctor3 } from './Bifunctor.js';
import * as chainable from './Chain.js';
import { Compactable3C } from './Compactable.js';
import * as E from './Either.js';
import { Filterable3C } from './Filterable.js';
import { FromEither3 } from './FromEither.js';
import { FromReader3 } from './FromReader.js';
import { LazyArg } from './function.js';
import { Functor3 } from './Functor.js';
import { Monad3, Monad3C } from './Monad.js';
import { MonadThrow3, MonadThrow3C } from './MonadThrow.js';
import { Monoid } from './Monoid.js';
import { Option } from './Option.js';
import { Pointed3 } from './Pointed.js';
import { Predicate } from './Predicate.js';
import * as R from './Reader.js';
import { ReadonlyNonEmptyArray } from './ReadonlyNonEmptyArray.js';
import { Refinement } from './Refinement.js';
import { Semigroup } from './Semigroup.js';
type Reader<R, A> = R.Reader<R, A>;
type Either<L, R> = E.Either<L, R>;
/**
 * @category model
 * @since 2.0.0
 */
export interface ReaderEither<R, E, A> extends Reader<R, Either<E, A>> {
}
/**
 * @category constructors
 * @since 2.0.0
 */
export declare const left: <R, E = never, A = never>(e: E) => ReaderEither<R, E, A>;
/**
 * @category constructors
 * @since 2.0.0
 */
export declare const right: <R, E = never, A = never>(a: A) => ReaderEither<R, E, A>;
/**
 * @category constructors
 * @since 2.0.0
 */
export declare const rightReader: <R, E = never, A = never>(ma: Reader<R, A>) => ReaderEither<R, E, A>;
/**
 * @category constructors
 * @since 2.0.0
 */
export declare const leftReader: <R, E = never, A = never>(me: Reader<R, E>) => ReaderEither<R, E, A>;
/**
 * @category conversions
 * @since 2.0.0
 */
export declare const fromEither: <E, A, R = unknown>(fa: Either<E, A>) => ReaderEither<R, E, A>;
/**
 * @category conversions
 * @since 2.11.0
 */
export declare const fromReader: <R, A, E = never>(fa: Reader<R, A>) => ReaderEither<R, E, A>;
/**
 * @category pattern matching
 * @since 2.10.0
 */
export declare const match: <E, B, A>(onLeft: (e: E) => B, onRight: (a: A) => B) => <R>(ma: ReaderEither<R, E, A>) => Reader<R, B>;
/**
 * Less strict version of [`match`](#match).
 *
 * The `W` suffix (short for **W**idening) means that the handler return types will be merged.
 *
 * @category pattern matching
 * @since 2.10.0
 */
export declare const matchW: <E, B, A, C>(onLeft: (e: E) => B, onRight: (a: A) => C) => <R>(ma: Reader<R, Either<E, A>>) => Reader<R, B | C>;
/**
 * The `E` suffix (short for **E**ffect) means that the handlers return an effect (`Reader`).
 *
 * @category pattern matching
 * @since 2.10.0
 */
export declare const matchE: <R, E, A, B>(onLeft: (e: E) => Reader<R, B>, onRight: (a: A) => Reader<R, B>) => (ma: ReaderEither<R, E, A>) => Reader<R, B>;
/**
 * Alias of [`matchE`](#matche).
 *
 * @category pattern matching
 * @since 2.0.0
 */
export declare const fold: <R, E, A, B>(onLeft: (e: E) => Reader<R, B>, onRight: (a: A) => Reader<R, B>) => (ma: ReaderEither<R, E, A>) => Reader<R, B>;
/**
 * Less strict version of [`matchE`](#matche).
 *
 * The `W` suffix (short for **W**idening) means that the handler return types will be merged.
 *
 * @category pattern matching
 * @since 2.10.0
 */
export declare const matchEW: <E, R2, B, A, R3, C>(onLeft: (e: E) => Reader<R2, B>, onRight: (a: A) => Reader<R3, C>) => <R1>(ma: ReaderEither<R1, E, A>) => Reader<R1 & R2 & R3, B | C>;
/**
 * Alias of [`matchEW`](#matchew).
 *
 * @category pattern matching
 * @since 2.10.0
 */
export declare const foldW: <E, R2, B, A, R3, C>(onLeft: (e: E) => Reader<R2, B>, onRight: (a: A) => Reader<R3, C>) => <R1>(ma: ReaderEither<R1, E, A>) => Reader<R1 & R2 & R3, B | C>;
/**
 * @category error handling
 * @since 2.0.0
 */
export declare const getOrElse: <E, R, A>(onLeft: (e: E) => Reader<R, A>) => (ma: ReaderEither<R, E, A>) => Reader<R, A>;
/**
 * Less strict version of [`getOrElse`](#getorelse).
 *
 * The `W` suffix (short for **W**idening) means that the handler return type will be merged.
 *
 * @category error handling
 * @since 2.6.0
 */
export declare const getOrElseW: <R2, E, B>(onLeft: (e: E) => Reader<R2, B>) => <R1, A>(ma: ReaderEither<R1, E, A>) => Reader<R1 & R2, A | B>;
/**
 * @category conversions
 * @since 2.10.0
 */
export declare const toUnion: <R, E, A>(fa: ReaderEither<R, E, A>) => Reader<R, E | A>;
/**
 * Changes the value of the local context during the execution of the action `ma` (similar to `Contravariant`'s
 * `contramap`).
 *
 * @since 2.0.0
 */
export declare const local: <R2, R1>(f: (r2: R2) => R1) => <E, A>(ma: ReaderEither<R1, E, A>) => ReaderEither<R2, E, A>;
/**
 * Less strict version of [`asksReaderEither`](#asksreadereither).
 *
 * The `W` suffix (short for **W**idening) means that the environment types will be merged.
 *
 * @category constructors
 * @since 2.11.0
 */
export declare const asksReaderEitherW: <R1, R2, E, A>(f: (r1: R1) => ReaderEither<R2, E, A>) => ReaderEither<R1 & R2, E, A>;
/**
 * Effectfully accesses the environment.
 *
 * @category constructors
 * @since 2.11.0
 */
export declare const asksReaderEither: <R, E, A>(f: (r: R) => ReaderEither<R, E, A>) => ReaderEither<R, E, A>;
/**
 * @category error handling
 * @since 2.0.0
 */
export declare const orElse: <E1, R, E2, A>(onLeft: (e: E1) => ReaderEither<R, E2, A>) => (ma: ReaderEither<R, E1, A>) => ReaderEither<R, E2, A>;
/**
 * Less strict version of [`orElse`](#orelse).
 *
 * The `W` suffix (short for **W**idening) means that the environment types and the return types will be merged.
 *
 * @category error handling
 * @since 2.10.0
 */
export declare const orElseW: <E1, R1, E2, B>(onLeft: (e: E1) => ReaderEither<R1, E2, B>) => <R2, A>(ma: ReaderEither<R2, E1, A>) => ReaderEither<R1 & R2, E2, A | B>;
/**
 * Returns an effect that effectfully "peeks" at the failure of this effect.
 *
 * @category error handling
 * @since 2.15.0
 */
export declare const tapError: {
    <E1, R2, E2, _>(onLeft: (e: E1) => ReaderEither<R2, E2, _>): <R1, A>(self: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, A>;
    <R1, E1, A, R2, E2, _>(self: ReaderEither<R1, E1, A>, onLeft: (e: E1) => ReaderEither<R2, E2, _>): ReaderEither<R1 & R2, E1 | E2, A>;
};
/**
 * @category error handling
 * @since 2.11.0
 */
export declare const orLeft: <E1, R, E2>(onLeft: (e: E1) => Reader<R, E2>) => <A>(fa: ReaderEither<R, E1, A>) => ReaderEither<R, E2, A>;
/**
 * @category error handling
 * @since 2.16.6
 */
export declare const orLeftW: <E1, R2, E2>(onLeft: (e: E1) => Reader<R2, E2>) => <R1, A>(fa: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E2, A>;
/**
 * @since 2.0.0
 */
export declare const swap: <R, E, A>(ma: ReaderEither<R, E, A>) => ReaderEither<R, A, E>;
/**
 * `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.
 *
 * @category mapping
 * @since 2.0.0
 */
export declare const map: <A, B>(f: (a: A) => B) => <R, E>(fa: ReaderEither<R, E, A>) => ReaderEither<R, E, B>;
/**
 * Returns a `ReaderEither` whose failure and success channels have been mapped by the specified pair of functions, `f` and `g`.
 *
 * @example
 * import * as ReaderEither from 'fp-ts/ReaderEither'
 * import * as Either from 'fp-ts/Either'
 *
 * const f = (s: string) => new Error(s)
 * const g = (n: number) => n * 2
 *
 * assert.deepStrictEqual(ReaderEither.mapBoth(ReaderEither.right(1), f, g)({}), Either.right(2))
 * assert.deepStrictEqual(ReaderEither.mapBoth(ReaderEither.left('err'), f, g)({}), Either.left(new Error('err')))
 *
 * @category error handling
 * @since 2.16.0
 */
export declare const mapBoth: {
    <E, G, A, B>(f: (e: E) => G, g: (a: A) => B): <R>(self: ReaderEither<R, E, A>) => ReaderEither<R, G, B>;
    <R, E, A, G, B>(self: ReaderEither<R, E, A>, f: (e: E) => G, g: (a: A) => B): ReaderEither<R, G, B>;
};
/**
 * Alias of `mapBoth`.
 *
 * @category legacy
 * @since 2.0.0
 */
export declare const bimap: <E, G, A, B>(f: (e: E) => G, g: (a: A) => B) => <R>(fa: ReaderEither<R, E, A>) => ReaderEither<R, G, B>;
/**
 * Returns a `ReaderEither` with its error channel mapped using the specified function.
 *
 * @example
 * import * as ReaderEither from 'fp-ts/ReaderEither'
 * import * as Either from 'fp-ts/Either'
 *
 * const f = (s: string) => new Error(s)
 *
 * assert.deepStrictEqual(ReaderEither.mapError(ReaderEither.right(1), f)({}), Either.right(1))
 * assert.deepStrictEqual(ReaderEither.mapError(ReaderEither.left('err'), f)({}), Either.left(new Error('err')))
 *
 * @category error handling
 * @since 2.16.0
 */
export declare const mapError: {
    <R, E, G>(f: (e: E) => G): <A>(self: ReaderEither<R, E, A>) => ReaderEither<R, G, A>;
    <R, E, A, G>(self: ReaderEither<R, E, A>, f: (e: E) => G): ReaderEither<R, G, A>;
};
/**
 * Alias of `mapError`.
 *
 * @category legacy
 * @since 2.0.0
 */
export declare const mapLeft: <E, G>(f: (e: E) => G) => <R, A>(fa: ReaderEither<R, E, A>) => ReaderEither<R, G, A>;
/**
 * @since 2.0.0
 */
export declare const ap: <R, E, A>(fa: ReaderEither<R, E, A>) => <B>(fab: ReaderEither<R, E, (a: A) => B>) => ReaderEither<R, E, B>;
/**
 * Less strict version of [`ap`](#ap).
 *
 * The `W` suffix (short for **W**idening) means that the environment types and the error types will be merged.
 *
 * @since 2.8.0
 */
export declare const apW: <R2, E2, A>(fa: ReaderEither<R2, E2, A>) => <R1, E1, B>(fab: ReaderEither<R1, E1, (a: A) => B>) => ReaderEither<R1 & R2, E1 | E2, B>;
/**
 * @category constructors
 * @since 2.8.5
 */
export declare const of: <R = unknown, E = never, A = never>(a: A) => ReaderEither<R, E, A>;
/**
 * @category sequencing
 * @since 2.14.0
 */
export declare const flatMap: {
    <A, R2, E2, B>(f: (a: A) => ReaderEither<R2, E2, B>): <R1, E1>(ma: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, B>;
    <R1, E1, A, R2, E2, B>(ma: ReaderEither<R1, E1, A>, f: (a: A) => ReaderEither<R2, E2, B>): ReaderEither<R1 & R2, E1 | E2, B>;
};
/**
 * Less strict version of [`flatten`](#flatten).
 *
 * The `W` suffix (short for **W**idening) means that the environment types and the error types will be merged.
 *
 * @category sequencing
 * @since 2.11.0
 */
export declare const flattenW: <R1, R2, E1, E2, A>(mma: ReaderEither<R1, E1, ReaderEither<R2, E2, A>>) => ReaderEither<R1 & R2, E1 | E2, A>;
/**
 * @category sequencing
 * @since 2.0.0
 */
export declare const flatten: <R, E, A>(mma: ReaderEither<R, E, ReaderEither<R, E, A>>) => ReaderEither<R, E, A>;
/**
 * Identifies an associative operation on a type constructor. It is similar to `Semigroup`, except that it applies to
 * types of kind `* -> *`.
 *
 * @category error handling
 * @since 2.0.0
 */
export declare const alt: <R, E, A>(that: () => ReaderEither<R, E, A>) => (fa: ReaderEither<R, E, A>) => ReaderEither<R, E, A>;
/**
 * Less strict version of [`alt`](#alt).
 *
 * The `W` suffix (short for **W**idening) means that the environment, the error and the return types will be merged.
 *
 * @category error handling
 * @since 2.9.0
 */
export declare const altW: <R2, E2, B>(that: () => ReaderEither<R2, E2, B>) => <R1, E1, A>(fa: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E2, A | B>;
/**
 * @since 2.7.0
 */
export declare const throwError: MonadThrow3<URI>['throwError'];
/**
 * @category type lambdas
 * @since 2.0.0
 */
export declare const URI = "ReaderEither";
/**
 * @category type lambdas
 * @since 2.0.0
 */
export type URI = typeof URI;
declare module './HKT.js' {
    interface URItoKind3<R, E, A> {
        readonly [URI]: ReaderEither<R, E, A>;
    }
}
/**
 * @category filtering
 * @since 2.10.0
 */
export declare const getCompactable: <E>(M: Monoid<E>) => Compactable3C<URI, E>;
/**
 * @category filtering
 * @since 2.10.0
 */
export declare function getFilterable<E>(M: Monoid<E>): Filterable3C<URI, E>;
/**
 * The default [`Applicative`](#applicative) instance returns the first error, if you want to
 * get all errors you need to provide a way to concatenate them via a `Semigroup`.
 *
 * See [`getApplicativeValidation`](./Either.ts.html#getapplicativevalidation).
 *
 * @category error handling
 * @since 2.7.0
 */
export declare function getApplicativeReaderValidation<E>(S: Semigroup<E>): Applicative3C<URI, E>;
/**
 * The default [`Alt`](#alt) instance returns the last error, if you want to
 * get all errors you need to provide a way to concatenate them via a `Semigroup`.
 *
 * See [`getAltValidation`](./Either.ts.html#getaltvalidation).
 *
 * @category error handling
 * @since 2.7.0
 */
export declare function getAltReaderValidation<E>(S: Semigroup<E>): Alt3C<URI, E>;
/**
 * @category instances
 * @since 2.7.0
 */
export declare const Functor: Functor3<URI>;
/**
 * Maps the `Right` value of this `ReaderEither` to the specified constant value.
 *
 * @category mapping
 * @since 2.16.0
 */
export declare const as: {
    <A>(a: A): <R, E, _>(self: ReaderEither<R, E, _>) => ReaderEither<R, E, A>;
    <R, E, _, A>(self: ReaderEither<R, E, _>, a: A): ReaderEither<R, E, A>;
};
/**
 * Maps the `Right` value of this `ReaderEither` to the void constant value.
 *
 * @category mapping
 * @since 2.16.0
 */
export declare const asUnit: <R, E, _>(self: ReaderEither<R, E, _>) => ReaderEither<R, E, void>;
/**
 * @category mapping
 * @since 2.10.0
 */
export declare const flap: <A>(a: A) => <R, E, B>(fab: import("./HKT.js").Kind3<"ReaderEither", R, E, (a: A) => B>) => import("./HKT.js").Kind3<"ReaderEither", R, E, B>;
/**
 * @category instances
 * @since 2.10.0
 */
export declare const Pointed: Pointed3<URI>;
/**
 * @category instances
 * @since 2.10.0
 */
export declare const Apply: Apply3<URI>;
/**
 * Combine two effectful actions, keeping only the result of the first.
 *
 * @since 2.0.0
 */
export declare const apFirst: <R, E, B>(second: ReaderEither<R, E, B>) => <A>(first: import("./HKT.js").Kind3<"ReaderEither", R, E, A>) => import("./HKT.js").Kind3<"ReaderEither", R, E, A>;
/**
 * Less strict version of [`apFirst`](#apfirst)
 *
 * The `W` suffix (short for **W**idening) means that the environment types and the error types will be merged.
 *
 * @since 2.12.0
 */
export declare const apFirstW: <R2, E2, B>(second: ReaderEither<R2, E2, B>) => <R1, E1, A>(first: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, A>;
/**
 * Combine two effectful actions, keeping only the result of the second.
 *
 * @since 2.0.0
 */
export declare const apSecond: <R, E, B>(second: ReaderEither<R, E, B>) => <A>(first: import("./HKT.js").Kind3<"ReaderEither", R, E, A>) => import("./HKT.js").Kind3<"ReaderEither", R, E, B>;
/**
 * Less strict version of [`apSecond`](#apsecond)
 *
 * The `W` suffix (short for **W**idening) means that the environment types and the error types will be merged.
 *
 * @since 2.12.0
 */
export declare const apSecondW: <R2, E2, B>(second: ReaderEither<R2, E2, B>) => <R1, E1, A>(first: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, B>;
/**
 * @category instances
 * @since 2.7.0
 */
export declare const Applicative: Applicative3<URI>;
/**
 * @category instances
 * @since 2.10.0
 */
export declare const Chain: chainable.Chain3<URI>;
/**
 * @category instances
 * @since 2.7.0
 */
export declare const Monad: Monad3<URI>;
/**
 * @category instances
 * @since 2.10.0
 */
export declare const FromEither: FromEither3<URI>;
/**
 * @category instances
 * @since 2.11.0
 */
export declare const FromReader: FromReader3<URI>;
/**
 * Composes computations in sequence, using the return value of one computation to determine the next computation and
 * keeping only the result of the first.
 *
 * @category combinators
 * @since 2.15.0
 */
export declare const tap: {
    <R1, E1, A, R2, E2, _>(self: ReaderEither<R1, E1, A>, f: (a: A) => ReaderEither<R2, E2, _>): ReaderEither<R1 & R2, E1 | E2, A>;
    <A, R2, E2, _>(f: (a: A) => ReaderEither<R2, E2, _>): <R1, E1>(self: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E2 | E1, A>;
};
/**
 * Composes computations in sequence, using the return value of one computation to determine the next computation and
 * keeping only the result of the first.
 *
 * @example
 * import * as E from 'fp-ts/Either'
 * import { pipe } from 'fp-ts/function'
 * import * as RE from 'fp-ts/ReaderEither'
 *
 * const checkString = (value: string) => pipe(
 *   RE.ask<number>(),
 *   RE.tapEither(
 *     (minLength) => value.length > minLength
 *       ? E.right('ok')
 *       : E.left('error')
 *   )
 * )
 *
 * assert.deepStrictEqual(checkString('')(1), E.left('error'))
 * assert.deepStrictEqual(checkString('fp-ts')(2), E.right(2))
 *
 * @category combinators
 * @since 2.16.0
 */
export declare const tapEither: {
    <A, E2, _>(f: (a: A) => Either<E2, _>): <R1, E1>(self: ReaderEither<R1, E1, A>) => ReaderEither<R1, E1 | E2, A>;
    <R1, E1, A, E2, _>(self: ReaderEither<R1, E1, A>, f: (a: A) => Either<E2, _>): ReaderEither<R1, E1 | E2, A>;
};
/**
 * Composes computations in sequence, using the return value of one computation to determine the next computation and
 * keeping only the result of the first.
 *
 * @category combinators
 * @since 2.16.0
 */
export declare const tapReader: {
    <R2, A, E, _>(f: (a: A) => Reader<R2, _>): <R1>(self: ReaderEither<R1, E, A>) => ReaderEither<R1 & R2, E, A>;
    <R1, R2, E, A, _>(self: ReaderEither<R1, E, A>, f: (a: A) => Reader<R2, _>): ReaderEither<R1 & R2, E, A>;
};
/**
 * @category instances
 * @since 2.7.0
 */
export declare const Bifunctor: Bifunctor3<URI>;
/**
 * @category instances
 * @since 2.7.0
 */
export declare const Alt: Alt3<URI>;
/**
 * Reads the current context.
 *
 * @category constructors
 * @since 2.0.0
 */
export declare const ask: <R, E = never>() => ReaderEither<R, E, R>;
/**
 * Projects a value from the global context in a `ReaderEither`.
 *
 * @category constructors
 * @since 2.0.0
 */
export declare const asks: <R, A, E = never>(f: (r: R) => A) => ReaderEither<R, E, A>;
/**
 * @category lifting
 * @since 2.11.0
 */
export declare const fromReaderK: <A extends ReadonlyArray<unknown>, R, B>(f: (...a: A) => Reader<R, B>) => <E = never>(...a: A) => ReaderEither<R, E, B>;
/**
 * Alias of `tapReader`.
 *
 * @category legacy
 * @since 2.11.0
 */
export declare const chainFirstReaderK: <A, R, B>(f: (a: A) => Reader<R, B>) => <E>(ma: ReaderEither<R, E, A>) => ReaderEither<R, E, A>;
/**
 * Alias of `tapReader`.
 *
 * Less strict version of [`chainReaderK`](#chainreaderk).
 *
 * The `W` suffix (short for **W**idening) means that the environment types will be merged.
 *
 * @category legacy
 * @since 2.11.0
 */
export declare const chainFirstReaderKW: <A, R1, B>(f: (a: A) => Reader<R1, B>) => <R2, E>(ma: ReaderEither<R2, E, A>) => ReaderEither<R1 & R2, E, A>;
/**
 * @category instances
 * @since 2.7.0
 */
export declare const MonadThrow: MonadThrow3<URI>;
/**
 * @category conversions
 * @since 2.0.0
 */
export declare const fromOption: <E>(onNone: LazyArg<E>) => <A, R = unknown>(fa: Option<A>) => ReaderEither<R, E, A>;
/**
 * Use `liftOption`.
 *
 * @category legacy
 * @since 2.10.0
 */
export declare const fromOptionK: <E>(onNone: LazyArg<E>) => <A extends ReadonlyArray<unknown>, B>(f: (...a: A) => Option<B>) => <R = unknown>(...a: A) => ReaderEither<R, E, B>;
/**
 * Use `flatMapOption`.
 *
 * @category legacy
 * @since 2.10.0
 */
export declare const chainOptionK: <E>(onNone: LazyArg<E>) => <A, B>(f: (a: A) => Option<B>) => <R>(ma: ReaderEither<R, E, A>) => ReaderEither<R, E, B>;
/**
 * Use `flatMapOption`.
 *
 * @category legacy
 * @since 2.13.2
 */
export declare const chainOptionKW: <E2>(onNone: LazyArg<E2>) => <A, B>(f: (a: A) => Option<B>) => <R, E1>(ma: ReaderEither<R, E1, A>) => ReaderEither<R, E1 | E2, B>;
/**
 * @category lifting
 * @since 2.15.0
 */
export declare const liftNullable: <A extends ReadonlyArray<unknown>, B, E>(f: (...a: A) => B | null | undefined, onNullable: (...a: A) => E) => <R>(...a: A) => ReaderEither<R, E, NonNullable<B>>;
/**
 * @category lifting
 * @since 2.15.0
 */
export declare const liftOption: <A extends ReadonlyArray<unknown>, B, E>(f: (...a: A) => Option<B>, onNone: (...a: A) => E) => <R>(...a: A) => ReaderEither<R, E, B>;
/**
 * @category sequencing
 * @since 2.15.0
 */
export declare const flatMapNullable: {
    <A, B, E2>(f: (a: A) => B | null | undefined, onNullable: (a: A) => E2): <R, E1>(self: ReaderEither<R, E1, A>) => ReaderEither<R, E2 | E1, NonNullable<B>>;
    <R, E1, A, B, E2>(self: ReaderEither<R, E1, A>, f: (a: A) => B | null | undefined, onNullable: (a: A) => E2): ReaderEither<R, E1 | E2, NonNullable<B>>;
};
/**
 * @category sequencing
 * @since 2.15.0
 */
export declare const flatMapOption: {
    <A, B, E2>(f: (a: A) => Option<B>, onNone: (a: A) => E2): <R, E1>(self: ReaderEither<R, E1, A>) => ReaderEither<R, E2 | E1, B>;
    <R, E1, A, B, E2>(self: ReaderEither<R, E1, A>, f: (a: A) => Option<B>, onNone: (a: A) => E2): ReaderEither<R, E1 | E2, B>;
};
/**
 * @category sequencing
 * @since 2.15.0
 */
export declare const flatMapEither: {
    <A, E2, B>(f: (a: A) => E.Either<E2, B>): <R, E1>(self: ReaderEither<R, E1, A>) => ReaderEither<R, E1 | E2, B>;
    <R, E1, A, E2, B>(self: ReaderEither<R, E1, A>, f: (a: A) => E.Either<E2, B>): ReaderEither<R, E1 | E2, B>;
};
/**
 * @category sequencing
 * @since 2.16.0
 */
export declare const flatMapReader: {
    <A, R2, B>(f: (a: A) => Reader<R2, B>): <R1, E>(self: ReaderEither<R1, E, A>) => ReaderEither<R1 & R2, E, B>;
    <R1, E, A, R2, B>(self: ReaderEither<R1, E, A>, f: (a: A) => Reader<R2, B>): ReaderEither<R1 & R2, E, B>;
};
/**
 * Alias of `flatMapEither`.
 *
 * @category legacy
 * @since 2.4.0
 */
export declare const chainEitherK: <E, A, B>(f: (a: A) => E.Either<E, B>) => <R>(ma: ReaderEither<R, E, A>) => ReaderEither<R, E, B>;
/**
 * Alias of `flatMapEither`.
 *
 * @category legacy
 * @since 2.6.1
 */
export declare const chainEitherKW: <E2, A, B>(f: (a: A) => Either<E2, B>) => <R, E1>(ma: ReaderEither<R, E1, A>) => ReaderEither<R, E1 | E2, B>;
/**
 * Alias of `tapEither`.
 *
 * @category legacy
 * @since 2.12.0
 */
export declare const chainFirstEitherK: <A, E, B>(f: (a: A) => E.Either<E, B>) => <R>(ma: ReaderEither<R, E, A>) => ReaderEither<R, E, A>;
/**
 * Alias of `tapEither`.
 *
 * Less strict version of [`chainFirstEitherK`](#chainfirsteitherk).
 *
 * The `W` suffix (short for **W**idening) means that the environment types will be merged.
 *
 * @category legacy
 * @since 2.12.0
 */
export declare const chainFirstEitherKW: <A, E2, B>(f: (a: A) => Either<E2, B>) => <R, E1>(ma: ReaderEither<R, E1, A>) => ReaderEither<R, E1 | E2, A>;
/**
 * Alias of `flatMapReader`.
 *
 * @category legacy
 * @since 2.11.0
 */
export declare const chainReaderK: <A, R, B>(f: (a: A) => Reader<R, B>) => <E>(ma: ReaderEither<R, E, A>) => ReaderEither<R, E, B>;
/**
 * Alias of `flatMapReader`.
 *
 * Less strict version of [`chainReaderK`](#chainreaderk).
 *
 * The `W` suffix (short for **W**idening) means that the environment types will be merged.
 *
 * @category legacy
 * @since 2.11.0
 */
export declare const chainReaderKW: <A, R2, B>(f: (a: A) => Reader<R2, B>) => <R1, E>(ma: ReaderEither<R1, E, A>) => ReaderEither<R1 & R2, E, B>;
/**
 * @category lifting
 * @since 2.0.0
 */
export declare const fromPredicate: {
    <E, A, B extends A>(refinement: Refinement<A, B>, onFalse: (a: A) => E): <R = unknown>(a: A) => ReaderEither<R, E, B>;
    <E, A>(predicate: Predicate<A>, onFalse: (a: A) => E): <R = unknown, B extends A = A>(b: B) => ReaderEither<R, E, B>;
    <E, A>(predicate: Predicate<A>, onFalse: (a: A) => E): <R = unknown>(a: A) => ReaderEither<R, E, A>;
};
/**
 * @category filtering
 * @since 2.0.0
 */
export declare const filterOrElse: {
    <E, A, B extends A>(refinement: Refinement<A, B>, onFalse: (a: A) => E): <R>(ma: ReaderEither<R, E, A>) => ReaderEither<R, E, B>;
    <E, A>(predicate: Predicate<A>, onFalse: (a: A) => E): <R, B extends A>(mb: ReaderEither<R, E, B>) => ReaderEither<R, E, B>;
    <E, A>(predicate: Predicate<A>, onFalse: (a: A) => E): <R>(ma: ReaderEither<R, E, A>) => ReaderEither<R, E, A>;
};
/**
 * Less strict version of [`filterOrElse`](#filterorelse).
 *
 * The `W` suffix (short for **W**idening) means that the error types will be merged.
 *
 * @category filtering
 * @since 2.9.0
 */
export declare const filterOrElseW: {
    <A, B extends A, E2>(refinement: Refinement<A, B>, onFalse: (a: A) => E2): <R, E1>(ma: ReaderEither<R, E1, A>) => ReaderEither<R, E1 | E2, B>;
    <A, E2>(predicate: Predicate<A>, onFalse: (a: A) => E2): <R, E1, B extends A>(mb: ReaderEither<R, E1, B>) => ReaderEither<R, E1 | E2, B>;
    <A, E2>(predicate: Predicate<A>, onFalse: (a: A) => E2): <R, E1>(ma: ReaderEither<R, E1, A>) => ReaderEither<R, E1 | E2, A>;
};
/**
 * @category lifting
 * @since 2.4.0
 */
export declare const fromEitherK: <E, A extends ReadonlyArray<unknown>, B>(f: (...a: A) => E.Either<E, B>) => <R = unknown>(...a: A) => ReaderEither<R, E, B>;
/**
 * @category do notation
 * @since 2.9.0
 */
export declare const Do: ReaderEither<unknown, never, {}>;
/**
 * @category do notation
 * @since 2.8.0
 */
export declare const bindTo: <N extends string>(name: N) => <R, E, A>(fa: import("./HKT.js").Kind3<"ReaderEither", R, E, A>) => import("./HKT.js").Kind3<"ReaderEither", R, E, { readonly [K in N]: A; }>;
declare const let_: <N extends string, A, B>(name: Exclude<N, keyof A>, f: (a: A) => B) => <R, E>(fa: import("./HKT.js").Kind3<"ReaderEither", R, E, A>) => import("./HKT.js").Kind3<"ReaderEither", R, E, { readonly [K in keyof A | N]: K extends keyof A ? A[K] : B; }>;
export { 
/**
 * @category do notation
 * @since 2.13.0
 */
let_ as let };
/**
 * @category do notation
 * @since 2.8.0
 */
export declare const bind: <N extends string, A, R, E, B>(name: Exclude<N, keyof A>, f: (a: A) => import("./HKT.js").Kind3<"ReaderEither", R, E, B>) => (ma: import("./HKT.js").Kind3<"ReaderEither", R, E, A>) => import("./HKT.js").Kind3<"ReaderEither", R, E, { readonly [K in keyof A | N]: K extends keyof A ? A[K] : B; }>;
/**
 * The `W` suffix (short for **W**idening) means that the environment types and the error types will be merged.
 *
 * @category do notation
 * @since 2.8.0
 */
export declare const bindW: <N extends string, A, R2, E2, B>(name: Exclude<N, keyof A>, f: (a: A) => ReaderEither<R2, E2, B>) => <R1, E1>(fa: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, {
    readonly [K in keyof A | N]: K extends keyof A ? A[K] : B;
}>;
/**
 * @category do notation
 * @since 2.8.0
 */
export declare const apS: <N extends string, A, R, E, B>(name: Exclude<N, keyof A>, fb: ReaderEither<R, E, B>) => (fa: import("./HKT.js").Kind3<"ReaderEither", R, E, A>) => import("./HKT.js").Kind3<"ReaderEither", R, E, { readonly [K in keyof A | N]: K extends keyof A ? A[K] : B; }>;
/**
 * Less strict version of [`apS`](#aps).
 *
 * The `W` suffix (short for **W**idening) means that the environment types and the error types will be merged.
 *
 * @category do notation
 * @since 2.8.0
 */
export declare const apSW: <A, N extends string, R2, E2, B>(name: Exclude<N, keyof A>, fb: ReaderEither<R2, E2, B>) => <R1, E1>(fa: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, {
    readonly [K in keyof A | N]: K extends keyof A ? A[K] : B;
}>;
/**
 * @since 2.11.0
 */
export declare const ApT: ReaderEither<unknown, never, readonly []>;
/**
 * Equivalent to `ReadonlyNonEmptyArray#traverseWithIndex(Applicative)`.
 *
 * @category traversing
 * @since 2.11.0
 */
export declare const traverseReadonlyNonEmptyArrayWithIndex: <A, R, E, B>(f: (index: number, a: A) => ReaderEither<R, E, B>) => ((as: ReadonlyNonEmptyArray<A>) => ReaderEither<R, E, ReadonlyNonEmptyArray<B>>);
/**
 * Equivalent to `ReadonlyArray#traverseWithIndex(Applicative)`.
 *
 * @category traversing
 * @since 2.11.0
 */
export declare const traverseReadonlyArrayWithIndex: <A, R, E, B>(f: (index: number, a: A) => ReaderEither<R, E, B>) => ((as: ReadonlyArray<A>) => ReaderEither<R, E, ReadonlyArray<B>>);
/**
 * Equivalent to `ReadonlyArray#traverseWithIndex(Applicative)`.
 *
 * @category traversing
 * @since 2.9.0
 */
export declare const traverseArrayWithIndex: <R, E, A, B>(f: (index: number, a: A) => ReaderEither<R, E, B>) => (as: ReadonlyArray<A>) => ReaderEither<R, E, ReadonlyArray<B>>;
/**
 * Equivalent to `ReadonlyArray#traverse(Applicative)`.
 *
 * @category traversing
 * @since 2.9.0
 */
export declare const traverseArray: <R, E, A, B>(f: (a: A) => ReaderEither<R, E, B>) => ((as: ReadonlyArray<A>) => ReaderEither<R, E, ReadonlyArray<B>>);
/**
 * Equivalent to `ReadonlyArray#sequence(Applicative)`.
 *
 * @category traversing
 * @since 2.9.0
 */
export declare const sequenceArray: <R, E, A>(arr: ReadonlyArray<ReaderEither<R, E, A>>) => ReaderEither<R, E, ReadonlyArray<A>>;
/**
 * Alias of `flatMap`.
 *
 * @category legacy
 * @since 2.0.0
 */
export declare const chain: <R, E, A, B>(f: (a: A) => ReaderEither<R, E, B>) => (ma: ReaderEither<R, E, A>) => ReaderEither<R, E, B>;
/**
 * Alias of `flatMap`.
 *
 * @category legacy
 * @since 2.6.0
 */
export declare const chainW: <R2, E2, A, B>(f: (a: A) => ReaderEither<R2, E2, B>) => <R1, E1>(ma: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, B>;
/**
 * Alias of `tap`.
 *
 * @category legacy
 * @since 2.0.0
 */
export declare const chainFirst: <R, E, A, B>(f: (a: A) => ReaderEither<R, E, B>) => (ma: ReaderEither<R, E, A>) => ReaderEither<R, E, A>;
/**
 * Alias of `tap`.
 *
 * @category legacy
 * @since 2.8.0
 */
export declare const chainFirstW: <R2, E2, A, B>(f: (a: A) => ReaderEither<R2, E2, B>) => <R1, E1>(ma: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, A>;
/**
 * Alias of `tapError`.
 *
 * @category legacy
 * @since 2.11.0
 */
export declare const orElseFirst: <E, R, B>(onLeft: (e: E) => ReaderEither<R, E, B>) => <A>(ma: ReaderEither<R, E, A>) => ReaderEither<R, E, A>;
/**
 * Alias of `tapError`.
 *
 * @category legacy
 * @since 2.11.0
 */
export declare const orElseFirstW: <E1, R2, E2, B>(onLeft: (e: E1) => ReaderEither<R2, E2, B>) => <R1, A>(ma: ReaderEither<R1, E1, A>) => ReaderEither<R1 & R2, E1 | E2, A>;
/**
 * This instance is deprecated, use small, specific instances instead.
 * For example if a function needs a `Functor` instance, pass `RE.Functor` instead of `RE.readerEither`
 * (where `R` is from `import R from 'fp-ts/ReaderEither'`)
 *
 * @category zone of death
 * @since 2.0.0
 * @deprecated
 */
export declare const readerEither: Monad3<URI> & Bifunctor3<URI> & Alt3<URI> & MonadThrow3<URI>;
/**
 * Use [`getApplySemigroup`](./Apply.ts.html#getapplysemigroup) instead.
 *
 * @category zone of death
 * @since 2.0.0
 * @deprecated
 */
export declare const getApplySemigroup: <R, E, A>(S: Semigroup<A>) => Semigroup<ReaderEither<R, E, A>>;
/**
 * Use [`getApplicativeMonoid`](./Applicative.ts.html#getapplicativemonoid) instead.
 *
 * @category zone of death
 * @since 2.0.0
 * @deprecated
 */
export declare const getApplyMonoid: <R, E, A>(M: Monoid<A>) => Monoid<ReaderEither<R, E, A>>;
/**
 * Use [`getApplySemigroup`](./Apply.ts.html#getapplysemigroup) instead.
 *
 * @category zone of death
 * @since 2.0.0
 * @deprecated
 */
export declare const getSemigroup: <R, E, A>(S: Semigroup<A>) => Semigroup<ReaderEither<R, E, A>>;
/**
 * Use [`getApplicativeReaderValidation`](#getapplicativereadervalidation) and [`getAltReaderValidation`](#getaltreadervalidation) instead.
 *
 * @category zone of death
 * @since 2.3.0
 * @deprecated
 */
export declare function getReaderValidation<E>(SE: Semigroup<E>): Monad3C<URI, E> & Bifunctor3<URI> & Alt3C<URI, E> & MonadThrow3C<URI, E>;