[Agda] making Agda on Lenny Debian

[Dan Rosén]

On Tue, Jul 24, 2012 at 8:05 PM, Wolfram Kahl <kahl at cas.mcmaster.ca> wrote:
> On Tue, Jul 24, 2012 at 09:58:18PM +0400, Serge D. Mechveliani wrote:
>> Further, making  Agda  needs calling `cabal'.
>
> Which comes from the package cabal-install.
>
> The package cabal only contains a library.
>
>> And the `cabal' command is not accessible for me at this stage.
>> So, I have additionally made from source and installed  Cabal-1.14.0  in
>> /home/mechvel/.cabal,
>
> This is what leads to the later conflict:
> Apparently your GHC already included Cabal-1.14.0,
> and by installing over it, you broke internal dependencies
> of your GHC library installation.

You can try to unregister them with ghc-pkg:

    ghc-pkg unregister Cabal-1.14.0

>
> As far as I know, the safest option is to start again from
> installing GHC,
> and then only install packages that are not already there
> for getting cabal-install.
>
> (You may even be able to use an existing cabal-install
>  with your new GHC.)

A lazier and a bit more brutal way when cabal packages are against you
is to remove your $HOME/.ghc and $HOME/.cabal folders. This requires
you to recompile (and re-download) your packages though, but otherwise
it should be fine.

Cheers,
Dan