@monstermann/fn/dist/set/isSubsetOf.js

A utility library for TypeScript.

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

//#region src/set/isSubsetOf.ts
/**
* `isSubsetOf(target, source)`
*
* Checks if the `target` set is a subset of the `source` set (i.e., all values in target exist in source). Returns `true` if target is a subset of source, `false` otherwise.
*
* ```ts
* isSubsetOf(new Set([1, 2]), new Set([1, 2, 3])); // true
* isSubsetOf(new Set([1, 4]), new Set([1, 2, 3])); // false
* ```
*
* ```ts
* pipe(new Set([1, 2]), isSubsetOf(new Set([1, 2, 3]))); // true
* pipe(new Set([1, 4]), isSubsetOf(new Set([1, 2, 3]))); // false
* ```
*/
const isSubsetOf = dfdlT((target, source) => {
	if (target.size > source.size) return false;
	for (const value of target) if (!source.has(value)) return false;
	return true;
}, 2);

//#endregion
export { isSubsetOf };