[arch-haskell] Re: [extra] haskell-parallel

[Magnus Therning]

On Thu, Nov 11, 2010 at 16:41, Peter Hercek <phercek at gmail.com> wrote:
> On 11/11/2010 05:16 PM, Magnus Therning wrote:
>>
>> On Thu, Nov 11, 2010 at 15:20, Peter Simons<simons at cryp.to>  wrote:
>>>
>>> Hi Magnus,
>>>
>>>  >  http://linode3.kiwilight.com/~magnus.therning/archhaskell/x86_64/
>>>
>>> I completely agree that the naming scheme is sound. I don't see, however,
>>> how other packages are going to use it. Could you show us a concrete
>>> example, please? What does a package like, say haskell-pandoc, depend on?
>>
>> It's dependencies would be unchanged.
>>
>> AFAICS there are roughly two sides to consider.  Packages delivered in
>> binary format, and packages delivered in source format (AUR).
>>
>> Binary
>>
>> The burden falls on the developers who provide the binary packages to
>> make sure that all binary packages are mutually compatible.
>>
>> Source
>>
>> The burden falls on the user to make sure that his system is sane.
>> Unfortunately it's rather simple to end up in a situation where this
>> isn't the case.  However, this is already true!
>> Here's an example:
>>
>> 1. User installs haskell-platform, and gets haskell-hp-http 4000.0.9
>> (which provides haskell-http 4000.0.9)
>> 2. User installs haskell-pandoc from AUR, it's built against HTTP 4000.0.9
>> 3. User now installs haskell-http 4000.0.10 from AUR
>> 4. User now removes haskell-hp-http, without removing/re-installing
>> haskell-pandoc
>>
>> Step four is possible, since all the dependencies of haskell-pandoc
>> are satisfied by the system (haskell-http>= 4000.0.5).
>
> Hmm, what we would need is so that when haskell-pandoc is being built it's
> PKGFILE is updated so that it requires haskell-http 4000.0.9 exactly. Then
> an attempt to uninstall haskell-hp-http later would require an
> uninstallation of haskell-pandoc too.
>
> Can pacman be forced to do this? We would need something like a new option
> in PKGFILE which would have meaning: "fix versions of dependencies of these
> packages exactly to the versions which are currently installed (installed
> during building)."

Just for reference, this is basically what the Debian policy on
Haskell packages is.

/M

-- 
Magnus Therning                        (OpenPGP: 0xAB4DFBA4)
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