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

[Peter Simons]

Hi Peter,

 > 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.

fortunately, Pacman does that already:

 | # pacman -R haskell-http
 | checking dependencies...
 | error: failed to prepare transaction (could not satisfy dependencies)
 | :: haskell-pandoc: requires haskell-http>=4000.0.5

It's not possible to remove a package that another installed package
depends on.

It's a different story, though, when a prerequisite is updated. Suppose
that pandoc has been installed. Now, an update of haskell-http shows up
an AUR. Pacman will perform that update, and it will break pandoc in the
process. This is why we have to bump pandoc's $pkgrel at the same time
we publish the update of haskell-http. In other words, an update of
package X requires $pkgrel bumps of all other packages that directly or
indirectly depend on X.

Take care,
Peter