has

function WeakValueMap<K, V>.has(key: K): boolean

Returns true if an entry with the specified key exists and its value has not been garbage collected, otherwise false.

Example

type User = { id: string; name: string };

const user1: User = { id: "user-1", name: "Alice" };

const cache = new WeakValueMap<string, User>();
cache.set("user-1", user1);

console.log(cache.has("user-1")); // true
console.log(cache.has("user-2")); // false