export type URI = typeof URI

export class Pair<A> {
  constructor(readonly fst: A, readonly snd: A) { ... }
  ...
}

first(f: Endomorphism<A>): Pair<A> { ... }

second(f: Endomorphism<A>): Pair<A> { ... }

swap(): Pair<A> { ... }

map<B>(f: (a: A) => B): Pair<B> { ... }

ap<B>(fab: Pair<(a: A) => B>): Pair<B> { ... }

ap_<B, C>(this: Pair<(b: B) => C>, fb: Pair<B>): Pair<C> { ... }

reduce<B>(b: B, f: (b: B, a: A) => B): B { ... }

extract(): A { ... }

extend<B>(f: (fb: Pair<A>) => B): Pair<B> { ... }

export const URI = ...

export const pair: Applicative1<URI> & Foldable2v1<URI> & Traversable2v1<URI> & Comonad1<URI> = ...

export const getMonoid = <A>(M: Monoid<A>): Monoid<Pair<A>> => ...

export const getOrd = <A>(O: Ord<A>): Ord<Pair<A>> => ...

export const getSemigroup = <A>(S: Semigroup<A>): Semigroup<Pair<A>> => ...

export const getSetoid = <A>(S: Setoid<A>): Setoid<Pair<A>> => ...