servant-multipart
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Relax lens lower bound
servant-multipart-0.11.3 depends on lens >= 4.17 && < 4.18, while the previous version depended on lens >= 4.0 && < 4.18.
servant-multipart uses four functions from Control.Lens, and looking at the lens changelog none of them seem to have recent changes to behaviour. Can the lower bound please be relaxed, and a metadata revision pushed to hackage?
(Among other things, this is currently breaking installing servant-multipart via nixpkgs on darwin.)
Thanks for reporting this issue!
Sure thing, I'll make a revision on hackage and reflect it in the repo later this morning (got to run right now).
I wonder how nixpkgs is broken.
Also note that latest servant-foreign also requires lens >= 4.17.
@endgame Hmm I just checked and the latest lens release is 4.17, which is included in both the previous version range and the one for servant-multipart-0.11.3, so I'm not sure exactly what the new bounds should be, and what the problem is. Could you show us the error message?
The version of lens currently in nixpkgs on my GNU/Linux and macOS/darwin machines both have lens-4.16.1.
Also, is servant-multipart using 0.15 specific features from {servant, servant-foreign, servant-server}? Those are also not currently in nixpkgs.
nixpkgs master has lens-4.17, so this is not especially pressing, but it would be nice to have since it's not using recent lens features.
Aaaaah, so we're requiring too recent a lens version...
Yes. From memory you're using view, (&), (.~) and (<>~), all of which have been around for a long time.
Note to self: lens-4.17 was uploaded at Tue Jul 3 17:05:19 UTC 2018; i.e. 6 months ago.
servant-multipart-0.11.3 at Tue Nov 13 22:03:02 UTC 2018, ~two months ago.
I'm really confused. Why you can upgrade to servant-multipart but cannot upgrade lens?
I'd rather poke at people maintaining packages with restricting upper bounds (I recall Chart at least has lens < 4.17 and other stuff)
At the time I reported this, nixpkgs on darwin had lens-4.16 and servant-multipart-0.11.3, and I was chasing build failures.
nixpkgs on my GNU/Linux machine is still giving me lens-4.16 but servant-multipart-0.11.2, so it builds.