Promises & then/catch

What optimization pattern does this implement?

const cache = new Map();

function memoize(fn) {
  return function(...args) {
    const key = JSON.stringify(args);
    if (cache.has(key)) {
      return Promise.resolve(cache.get(key));
    }
    return fn(...args).then(result => {
      cache.set(key, result);
      return result;
    });
  };
}

Lazy loading
Caching
This implements Promise memoization/caching: 1) Caches Promise results based on function arguments, 2) Returns cached results immediately as resolved Promises, 3) Only executes the actual operation for uncached values, 4) Maintains Promise interface even for cached values, 5) Useful for expensive operations that are called repeatedly with the same arguments, 6) Common in data fetching and computational operations.
Batching
Prefetching

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