Function computeIfAbsent

Queries the map for the given key and returns its associated value, if it is present.

If the key is absent, then the producer will be invoked. The computed value will be associated with the given key and returned.

Example

export function lazyLookup<K, V>(
  producer: (key: K) => V,
  cache: PickMap<K, V, 'has' | 'set' | 'get'> = new Map()
) {
  return (key: K): V => computeIfAbsent(cache, key, producer);
}