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

On 11/11/2010 05:16 PM, Magnus Therning wrote:

On Thu, Nov 11, 2010 at 15:20, Peter Simons wrote:

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Hi Magnus,

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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)."