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

A utility library for TypeScript.

import { FnError } from "../function/FnError.js";
import { dfdlT } from "@monstermann/dfdl";
import { cloneMap } from "@monstermann/remmi";

//#region src/map/removeOrThrow.ts
/**
* `removeOrThrow(map, key)`
*
* Removes the entry with the specified `key` from `map`, throwing an error if the key doesn't exist.
*
* ```ts
* removeOrThrow(
*     new Map([
*         ["a", 1],
*         ["b", 2],
*     ]),
*     "a",
* ); // Map(1) { "b" => 2 }
*
* removeOrThrow(
*     new Map([
*         ["a", 1],
*         ["b", 2],
*     ]),
*     "c",
* ); // throws FnError
* ```
*
* ```ts
* pipe(
*     new Map([
*         ["a", 1],
*         ["b", 2],
*     ]),
*     removeOrThrow("a"),
* ); // Map(1) { "b" => 2 }
*
* pipe(
*     new Map([
*         ["a", 1],
*         ["b", 2],
*     ]),
*     removeOrThrow("c"),
* ); // throws FnError
* ```
*/
const removeOrThrow = dfdlT((target, key) => {
	if (!target.has(key)) throw new FnError("Map.removeOrThrow: Key does not exist.", [target, key]);
	const result = cloneMap(target);
	result.delete(key);
	return result;
}, 2);

//#endregion
export { removeOrThrow };