sof patch for --ghc-pkg-config-file=

[Isaac Jones]

Duncan Coutts <duncan.coutts at worc.ox.ac.uk> writes:

> On Fri, 2006-09-15 at 10:06 -0700, Isaac Jones wrote:
>> Emailing to libraries@, please followup to cabal-devel.
>> 
>> Here's a patch from Sigbjorn which adds --ghc-pkg-config-file= to
>> cabal.  This is an oldish patch, but I haven't stopped getting
>> requests for this feature :)
>> 
>> This allows you to create a "local" package config file, rather than
>> using the --user or --global files, this is useful for in-place
>> building, as when you're developing a set of related packages.
>> 
>> I still have some debate about whether this patch should go in; it
>> assumes a model of package registration where you have a config file
>> (as opposed to a directory) which isn't the case for nhc or Hugs.  But
>> the idea doesn't seem to bother anyone but me, and the flag is clearly
>> marked as a ghc-related flag, so I'm thinking of letting it through.
>> Opinions?
>
> Note that there is already a register --inplace flag to register a
> package in the build tree. 

And this is mostly so you can build in the build tree, register to
--user (or global), muck around a bit, and presumably unregister the
package later.

> To allow multiple packages to be built against each other inplace
> we'd also need some flag for configure.

To specify the package file location, you mean?

I guess you could do something sloppy like:

cd my-package
./setup build
./setup register --inplace --user

cd my-other-package
./setup configure --user
etc

ghc-pkg unregister my-package --user 

(which is what I just did for cabal & cabal-install.)

> Would this be enough? Do we really also need the ability to specify
> arbitrary package databases? What is the use case?

I think it's mainly for registering packages together in a build tree.


peace,

  isaac