Dependencies/backwards compatibility in Hackage

[Björn Bringert]

Ross Paterson wrote:
> On Thu, Feb 01, 2007 at 12:57:01PM +0100, Sven Moritz Hallberg wrote:
>> While trying out cabal-install today, I stumbled across the following:
>> I wanted to install XmlRpc which depends on HaXml and works with
>> HaXml-1.13.2. However, HaXml-1.17 which has also been uploaded to
>> hackageDB changed an exposed module's name and XmlRpc doesn't work with
>> it anymore.
>>
>> I'm wondering how to avoid such situations. I appears to me that
>> expecting the maintainer of every package depending on HaXml to update
>> their dependencies "after the fact" doesn't make sense because it leaves
>> an arbitrarily long window where the package won't build straight out
>> of hackageDB.
> 
> We could decide on a standard interpretation of version numbers, e.g.
> major.minor.patch.  To support this, we'd want wildcards like 1.13.*
> in version ranges.
> 
> In the meantime, I'll remove HaXml-1.17 from HackageDB.

I think that the correct solution to this problem would be to make a new 
release of haxr (which used to be XmlRpc) that works with HaXml 1.17.

On a side note, I think that XmlRpc should be removed, or there should 
be a way for one package to obsolete another. The XmlRpc package has 
been renamed to haxr, to have a more uniform naming within the package.

/Björn