esnext.collection.d.ts

/// <reference lib="es2025.collection" />

interface Map<K, V> {
    /**
     * Returns a specified element from the Map object.
     * If no element is associated with the specified key, a new element with the value `defaultValue` will be inserted into the Map and returned.
     * @returns The element associated with the specified key, which will be `defaultValue` if no element previously existed.
     */
    getOrInsert(key: K, defaultValue: V): V;
    /**
     * Returns a specified element from the Map object.
     * If no element is associated with the specified key, the result of passing the specified key to the `callback` function will be inserted into the Map and returned.
     * @returns The element associated with the specific key, which will be the newly computed value if no element previously existed.
     */
    getOrInsertComputed(key: K, callback: (key: K) => V): V;
}

interface WeakMap<K extends WeakKey, V> {
    /**
     * Returns a specified element from the WeakMap object.
     * If no element is associated with the specified key, a new element with the value `defaultValue` will be inserted into the WeakMap and returned.
     * @returns The element associated with the specified key, which will be `defaultValue` if no element previously existed.
     */
    getOrInsert(key: K, defaultValue: V): V;
    /**
     * Returns a specified element from the WeakMap object.
     * If no element is associated with the specified key, the result of passing the specified key to the `callback` function will be inserted into the WeakMap and returned.
     * @returns The element associated with the specific key, which will be the newly computed value if no element previously existed.
     */
    getOrInsertComputed(key: K, callback: (key: K) => V): V;
}