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

[Peter Hercek]

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)."