Cabal compatibility redeux
robdockins at fastmail.fm
Mon Jan 9 19:04:39 EST 2006
I'd just like to reseruct the conversation from here
(http://www.haskell.org//pipermail/libraries/2005-December/004692.html) for a
quick moment if I might. At the time I wrote:
>>>> This would greatly simplify the Distribution.Simple.UserHooks
>>>> structure bringing it from 34 fields to 14 fields, or so.
>>>> Downsides: Making pre and post hooks would now be slightly harder, and
>>>> it would break existing hooks-using code.
>>> I just want to mention that these kind of changes represent represent a
>>> VERY big problem. I discussed that issue at some length in an email I
>>> intended to send to this list very recently, but it seems to have gotten
>> Are you sure they represent a very big problem in practice and not
>> just in theory?
> Well, obviously it isn't a practical problem yet. If it was we'd have
> people screaming about it on the lists.
I would now like to add to the theoretical arguments I made then the evidence
that the HSQL driver package for MySQL uses the user hooks of Cabal and I
have just experienced a case of Cabal version skew breaking a build system,
because this package will not build for me using Cabal 1.1.3. I am unsure at
the moment if this is because my Cabal is too new or too old, and I now face
the prospect of 1) hacking on the build system to match my cabal, 2) trying
random cabal upgrades/downgrades or 3) pinging the package maintainers to
figure out how to build this package.
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