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/** * This file contains the Identity algebraic data type. Identity is one of the * simplest data types in that it represents a type AS IS, allowing one to * create algebraic structures for the inner type. This is most useful for * constructing arrow optics. * * @module Identity * @since 2.0.0 */import type { Kind, Out } from "./kind.ts";import type { Applicable } from "./applicable.ts";import type { Mappable } from "./mappable.ts";import type { Flatmappable } from "./flatmappable.ts";import type { Wrappable } from "./wrappable.ts";
/** * @since 2.0.0 */export type Identity<A> = A;
/** * @since 2.0.0 */export interface KindIdentity extends Kind {  readonly kind: Identity<Out<this, 0>>;}
/** * @since 2.0.0 */export function wrap<A>(a: A): Identity<A> {  return a;}
/** * @since 2.0.0 */export function map<A, I>(  fai: (a: A) => I,): (ta: Identity<A>) => Identity<I> {  return fai;}
/** * @since 2.0.0 */export function apply<A>(  ua: Identity<A>,): <I>(ufai: Identity<(a: A) => I>) => Identity<I> {  return (ufai) => ufai(ua);}
/** * @since 2.0.0 */export function flatmap<A, I>(  fati: (a: A) => Identity<I>,): (ta: Identity<A>) => Identity<I> {  return fati;}
/** * @since 2.0.0 */export const ApplicableIdentity: Applicable<KindIdentity> = {  apply,  map,  wrap,};
/** * @since 2.0.0 */export const MappableIdentity: Mappable<KindIdentity> = { map };
/** * @since 2.0.0 */export const FlatmappableIdentity: Flatmappable<KindIdentity> = {  apply,  map,  flatmap,  wrap,};
/** * @since 2.0.0 */export const WrappableIdentity: Wrappable<KindIdentity> = { wrap };