# Extract

## extract

Signature

``````export declare const extract: <E, A>(wa: [A, E]) => A
``````

# folding

## foldMap

Signature

``````export declare const foldMap: <M>(M: Monoid<M>) => <A>(f: (a: A) => M) => <E>(fa: [A, E]) => M
``````

## reduce

Signature

``````export declare const reduce: <A, B>(b: B, f: (b: B, a: A) => B) => <E>(fa: [A, E]) => B
``````

## reduceRight

Signature

``````export declare const reduceRight: <A, B>(b: B, f: (a: A, b: B) => B) => <E>(fa: [A, E]) => B
``````

# instances

## Bifunctor

Signature

``````export declare const Bifunctor: Bifunctor2<'Tuple'>
``````

Signature

``````export declare const Comonad: Comonad2<'Tuple'>
``````

## Foldable

Signature

``````export declare const Foldable: Foldable2<'Tuple'>
``````

## Functor

Signature

``````export declare const Functor: Functor2<'Tuple'>
``````

## Semigroupoid

Signature

``````export declare const Semigroupoid: Semigroupoid2<'Tuple'>
``````

## Traversable

Signature

``````export declare const Traversable: Traversable2<'Tuple'>
``````

## getApplicative

Signature

``````export declare function getApplicative<M>(M: Monoid<M>): Applicative2C<URI, M>
``````

## getApply

Signature

``````export declare function getApply<S>(S: Semigroup<S>): Apply2C<URI, S>
``````

## getChain

Signature

``````export declare function getChain<S>(S: Semigroup<S>): Chain2C<URI, S>
``````

## getChainRec

Signature

``````export declare function getChainRec<M>(M: Monoid<M>): ChainRec2C<URI, M>
``````

Signature

``````export declare function getMonad<M>(M: Monoid<M>): Monad2C<URI, M>
``````

# mapping

## bimap

Map a pair of functions over the two type arguments of the bifunctor.

Signature

``````export declare const bimap: <E, G, A, B>(mapSnd: (e: E) => G, mapFst: (a: A) => B) => (fa: [A, E]) => [B, G]
``````

## flap

Signature

``````export declare const flap: <A>(a: A) => <E, B>(fab: [(a: A) => B, E]) => [B, E]
``````

## mapFst

Map a function over the first component of a `Tuple`.

This is the `map` operation of the `Functor` instance.

Signature

``````export declare const mapFst: <A, B>(f: (a: A) => B) => <E>(fa: [A, E]) => [B, E]
``````

## mapSnd

Map a function over the second component of a `Tuple`.

This is the `mapLeft` operation of the `Bifunctor` instance.

Signature

``````export declare const mapSnd: <E, G>(f: (e: E) => G) => <A>(fa: [A, E]) => [A, G]
``````

# traversing

## sequence

Signature

``````export declare const sequence: Sequence2<'Tuple'>
``````

## traverse

Signature

``````export declare const traverse: PipeableTraverse2<'Tuple'>
``````

# type lambdas

## URI

Signature

``````export declare const URI: 'Tuple'
``````

## URI (type alias)

Signature

``````export type URI = typeof URI
``````

# utils

## compose

Signature

``````export declare const compose: <A, B>(ab: [B, A]) => <C>(bc: [C, B]) => [C, A]
``````

## duplicate

Signature

``````export declare const duplicate: <E, A>(wa: [A, E]) => [[A, E], E]
``````

## extend

Signature

``````export declare const extend: <E, A, B>(f: (wa: [A, E]) => B) => (wa: [A, E]) => [B, E]
``````

## fst

Signature

``````export declare const fst: <A, E>(ea: [A, E]) => A
``````

## snd

Signature

``````export declare const snd: <A, E>(ea: [A, E]) => E
``````

## swap

Signature

``````export declare const swap: <A, E>(ea: [A, E]) => [E, A]
``````

# zone of death

## mapLeft

Use `mapSnd` instead.

Signature

``````export declare const mapLeft: <E, G>(f: (e: E) => G) => <A>(fa: [A, E]) => [A, G]
``````

## map

Use `mapFst` instead.

Signature

``````export declare const map: <A, B>(f: (a: A) => B) => <E>(fa: [A, E]) => [B, E]
``````

## tuple

This instance is deprecated, use small, specific instances instead. For example if a function needs a `Functor` instance, pass `T.Functor` instead of `T.tuple` (where `T` is from `import T from 'fp-ts/Tuple'`)

Signature

``````export declare const tuple: Semigroupoid2<'Tuple'> &
Bifunctor2<'Tuple'> &