Adding a world file to cabal-install

[Andrea Vezzosi]

On Fri, Feb 6, 2009 at 3:18 PM, Peter Robinson <thaldyron at gmail.com> wrote:
> Hello,
>
> I recently upgraded GHC on one of my machines and therefore had to
> reinstall all installed packages. Granted, cabal-install makes this a lot
> easier nowadays, but I saw that there's a ticket [1] for
> adding a "world" file (speaking in Gentoo terminology) that records all
> user requested packages, so I gave that a try. You can find a patch for
> the Head branch that adds preliminary support here:
> http://darcs.monoid.at/cabal-install/
>
> Basically the patch adds Distribution.Client.World that provides an
> /insert/, /delete/, and /getContents/ interface. /World.insert/ is called
> from Distribution.Client.Install upon successful build.
> What's currently missing is the implementation of a cabal command that
> rebuilds the package list from ~/.cabal/world (or some other location
> set by the currently also missing configuration options).
>
> 1. The world file only contains the list of package names and versions
> as requested by the user. I suppose that's all that's needed for
> rebuilding, right?

We also need the values for the flags specified by the user, i think.