Two implementations of delaySubscription

17 Apr 2021 ⇐ Notes archive

(This is an entry in my technical notebook. There will likely be typos, mistakes, or wider logical leaps — the intent here is to “let others look over my shoulder while I figure things out.”)

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Jack Stone’s proposal and implementation of Publisher.delaySubscription was a TIL for me. I also didn’t know there was prior art for the operator in Rx.

It’s different than Publisher.delay in that it shifts the point of subscription forward in time instead of emissions (à la delay).

The primary step is holding a received subscription for the specified delay before forwarding it downstream. Which begs my favorite question, can this be implemented as composed operator? It can! An approach is tucked away in isowords’ repo under the Effect.deferred naming, where the Point-Free team uses it delay a Never-Never sound effect until after a game cube is removed.