[Nix-dev] Would this be a way to solve the ghc-pkg install wrapper/libraries issue?

[Michael Raskin]

Marc Weber wrote:
> Now when using nix-env -i (
perhaps a graphical ui later on) would see
> some kind of tree:
> 
> applications you want to install
>   * vim
>   * wine
>   * gtk
>   * ...
>   * ghc-6.1 wrapper with user selected libraries
>     - libraries to install with ghc 6.1
>         * HappY
>         * hadock
>         * mtl
>         * ...
> 
> The selection could be written to database .. and you got it?
> magicUserSelection can read the db and filter the list..

I think that magicUserSelection should just read some actual
configuration file. Maybe it should be just in ~ for users and global
for default profile. Maybe we should basically have generator that gets
some mix of actual libraries and null's and builds a wrapper, each user
will on low-level invoke installation of 'ghc-wrapper {happySupport=true
; hadockSupport=false;}'..
How I understood one of the ideas of Nix (and it was one of the
attracting points) is the following: you have system.nix, it and its
dependencies describe everything; you can write down svn revision
number, copy configuration.nix and go to any NixOS box, when you do
'nixos-rebuild switch; reboot' you will end up in the same software
environment (that keeps me from using nix-env, by the way). So I think
that there should be a limited set of configuration files outside the
SVN tree, and maximum of what should be allowed to any UI frontends is
comfortably customize all the settings in these text-only human-editable
files.