sneako/finch

Finch.stream: Return `{:cont, acc} | {:halt, acc}`

wojtekmach opened this issue · 5 comments

wojtekmach commented

Currently the given function returns possibly updated accumulator. If we want to cancel the request we need to exit/throw/raise. Should we change the contract so that we return {:cont, acc} | {:halt, acc}, the latter cancelling the request under the hood?

I don't have a particular use case in mind at the moment, just wondering cause we wouldn't be able to change it after v1.0. If we were to move forward with this, I think we could assist users with a deprecation if their callback does not return the shape. (It would be a breakage if they happen to return the exact tuple in their accumulator.)

cc @josevalim

josevalim commented

Yeah, it is probably worth moving to this style, even though it is a bit verbose. Alternatively we can call it Finch.stream_while, to mirror Enum.reduce_while.

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zachallaun commented

Finch.stream_while sounds great and fixes the backwards compatibility issue. Could also potentially deprecate Finch.stream/5 and encourage rewriting to Finch.stream_while.

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sneako commented

Finch.stream_while sounds good to me!

dlindenkreuz commented

@sneako Can you create a release for this?

sneako commented

@dlindenkreuz I have just released 0.17.0 🎉

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