It was announced, about 3 months ago, http://coldwa.st/e/blog/2017-09-09-Cabal-2-0.html along with the future intention of this syntax and how it differs from
#14558: Unable to parse integer-gmp's Cabal file -------------------------------------+------------------------------------- Reporter: taylorfausak | Owner: hvr Type: task | Status: new Priority: normal | Milestone: Component: Core Libraries | Version: 8.2.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by svenpanne): Replying to [comment:28 Phyx-]: the strong bounded versions: [...] Hmmm, this is still confusing: On the one hand it is said (https://www.haskell.org/cabal/users-guide/developing- packages.html?highlight=caret#pkg-field-build-depends) that the new syntax is ''exactly'' equivalent to the old syntax using `>=` and `<`. OTOH, http://coldwa.st/e/blog/2017-09-09-Cabal-2-0.html states that it has different semantics. Furthermore, I still don't get the difference between the new `^>=` operator and leaving out the upper bound completely. Surely the latter can't really mean "I promise I work with every following version", in the absence of clairvoyant abilities this would be a lie. So using only `>=` without an upper bound seems to be equivalent to the new operator, I fail to see another sensible interpretation.
[...] It was designed and approved in public https://github.com/haskell/cabal/pull/3705 it was publicly posted on reddit https://www.reddit.com/r/haskell/comments/6z2gja/whats_new_in_cabalcabalinst...
And the migration plan was outlined https://github.com/haskell/cabal/issues/4899.
Perhaps I'm getting a little bit old, but I consider neither reddit nor twitter as a source of serious information. Nothing was posted on the haskell, haskell-cafe or ghc-dev mailing lists about it. The only thing I was able to find was a Haskell Weekly issue pointing to the blog, having the feature buried in the middle of a multi-page item list, which is a bit indirect IMHO.
Could it be that perhaps a lot of people here don't read Cabal release information? Or follow Cabal development? [...]
Serious non-aggressive question: As a developer using ''only'' stack, why should I read the Cabal release information or even follow Cabal development? Note that I am not hostile towards the project or something like that, it's just that I am not interested in it anymore because stack is a much better fit for my work. My expectation from a library developer POV would be some explicit hint about changes in the ecosystem, not about changes in some tool I don't use.
[...] The fact is, the change was not done in secret, the feature not developed in secret. The change was communicated well ahead of time and on channels that lots of you frequent.
As mentioned above, I think it would have been great if this had been posted on one of the Haskell mailing lists, which I still consider ''the'' channel to get information from. Not everybody has the time and energy to read all those various (and most of the time uninformative and time sucking) communication channels which beg for your attention... :-/ -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14558#comment:31 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler