[Nix-dev] emacsPackages

[Peter Simons]

Hi Florian,

the problem with the current scheme is you cannot install a non-default
version of an Emacs package into a profile and keep it up-to-date with
nix-env -u \*. If you update the profile, you'll be switched back to
whatever happens to be listed first in all-packages.nix. The only
reliable way to refer to an Emacs package is by attribute. Under these
circumstances, it's a mistake to use "recurseIntoAttrs" with more than
one package set.

I guess, what we should do is bake the emacs version used to build that
package into the package name -- like we do in haskellPackages --, but I
don't have time to make those changes right now. :-(

Take care,
Peter