Function cached

cached<ArgsType extends unknown[], T, K = unknown>(
fn: (...args: ArgsType) => Promise<T>,
keyGenerator?: (...args: ArgsType) => K,
): CachedFunction<ArgsType, T>
Creates a memoized async function that deduplicates in-flight requests and caches results.

Subsequent calls with the same cache key receive the original promise (request coalescing). If the promise rejects, the entry is evicted so the next call can retry.
Type Parameters
- ArgsType extends unknown[]
  Tuple of the function's parameter types.
- T
  The resolved return type.
- K = unknown
  The cache key type.
Parameters
- fn: (...args: ArgsType) => Promise<T>
  The async function to memoize.
- OptionalkeyGenerator: (...args: ArgsType) => K
  Derives a cache key from arguments. Defaults to JSON.stringify.
Returns CachedFunction<ArgsType, T>
A CachedFunction with an additional .clearCache() method.
Remarks
Rejections are not cached. To cache negative results, resolve with Result<T, E> or null.
Example
```
const cachedFetch = cached(async (id: string) => fetch(`/users/${id}`).then(r => r.json()));
await cachedFetch("42"); // executes fetch
await cachedFetch("42"); // returns cached promise
cachedFetch.clearCache();
```
- Defined in src/function/cache.ts:39