@monstermann/fn/dist/map/removeOrElse.js

A utility library for TypeScript.

import { dfdlT } from "@monstermann/dfdl";
import { cloneMap } from "@monstermann/remmi";

//#region src/map/removeOrElse.ts
/**
* `removeOrElse(map, key, orElse)`
*
* Removes the entry with the specified `key` from `map`, calling `orElse` with the map if the key doesn't exist.
*
* ```ts
* removeOrElse(
*     new Map([
*         ["a", 1],
*         ["b", 2],
*     ]),
*     "a",
*     () => null,
* ); // Map(1) { "b" => 2 }
*
* removeOrElse(
*     new Map([
*         ["a", 1],
*         ["b", 2],
*     ]),
*     "c",
*     (map) => map.size,
* ); // 2
* ```
*
* ```ts
* pipe(
*     new Map([
*         ["a", 1],
*         ["b", 2],
*     ]),
*     removeOrElse("a", () => null),
* ); // Map(1) { "b" => 2 }
*
* pipe(
*     new Map([
*         ["a", 1],
*         ["b", 2],
*     ]),
*     removeOrElse("c", (map) => map.size),
* ); // 2
* ```
*/
const removeOrElse = dfdlT((target, key, orElse) => {
	if (!target.has(key)) return orElse(target);
	const result = cloneMap(target);
	result.delete(key);
	return result;
}, 3);

//#endregion
export { removeOrElse };