extracted cache class, persist & dispose

[bbohlender]

I have a case where I need to persist a value through a suspension. So a value should be "persistent", similar to useMemo, but when working with suspense. I could use a suspend with a promise that resolves directly, but that is not ideal.

I like the cache implementation in this library pretty much, so I thought of adapting it to a "persist" library, but since both would have so much in common, maybe the addition of the persist function is a good fit here.

Additionally, I extracted the insert, delete and get functionality in a separate class so there can be two different caches for asynchronous cache entries and synchronous cache entries (that is how I called them, at least).

If my changes are too disruptive or the persist idea does not fit this library, I would love to hear some feedback on different solutions for my problem or different options to publish my solution.

Thanks 😄

[drcmda]

could you make a small pseudo code example what you need to accomplish? i don't understand what you mean when you say: persist working with suspense.

with preload and clear you have access to the cache, and you can store items that are then immediately accessible. is that unrelated?

[bbohlender]

Yeah, you are right, thanks! preload and peek should do the trick 👍 For completeness here the persist function I came up with 😄 (not tested yet)

function persist<T, Keys extends Array<unknown>, Fn extends (...keys: Keys) => T>(
    fn: Fn,
    keys: Keys,
    config: Partial<{
        lifespan?: number
        equal?: (a: any, b: any) => boolean
    }> = {}
): T {
    let result = peek(keys) as T
    if (result == null) {
        result = fn(...keys)
        preload(() => Promise.resolve(result), keys, config)
    }
    return result
}