1) The wrapper erroneously used the ghc-pkg flag "--package-db" instead of
"--global-package-db". The result was that packages installed locally in
~/.ghc and ~/.cabal were invisible to GHC. This has been fixed.
2) The wrapper now deals gracefully with an empty package set: if no package
is requested to be included in the wrapped environment, the wrapper just
installs a pristine GHC.
3) Correctly configure the "docdir" path returned by ghc-paths.
4) Added some comments that describe the idea behind our ghc-paths patches and
gives users same sample shell code that can be used to import our special
environment variables into the currently running shell, so that programs
outside of the wrapped environment can use them, too.
- It now uses JavaScript for configuration (only),
so I had to "convert" config for NetworkManager.
- I tested suspend/restart/(un)mount on KDE/Xfce,
Phreedom tested NetworkManager config conversion.
The default setting for extraLibs used to be the set of modules that come with
python by default but aren't usually enabled in our standard python derivation
because they require additional libraries. This meant that users who want to
*add* libraries to that set had to use a fairly complicated override, to add
more entries without loosing the ones set by default.
After this patch, the "standard libraries" such as "curses' are listed in
stdLibs while the extraLibs argument remains empty by default. This allows
users to override extraLibs without overriding the standard libraries.
Furthermore, the wrapper environment can be messed around with in an
additional 'postBuild' step. One nice application of this build step is
to patch scripts and binaries to use the wrapped python interpreter
instead of the pristine one, thereby enabling them to pick up all
modules that have been configured. The following example shows how this
is done for the 'pylint' utility:
pkgs.python27Full.override {
extraLibs = [pkgs.pylint];
postBuild = ''
cd ${pkgs.pylint}/bin
for i in *; do
rm $out/bin/$i
sed -r -e "s|^exec |exec $out/bin/python -- |" <$i >$out/bin/$i
chmod +x $out/bin/$i
done;
'';
};
The ghcWithPackage expression now has an argument 'ignoreCollisions' that
allows users to disable the path collision check like so:
(pkgs.haskellPackages.ghcWithPackages (pkgs: with pkgs; [ haskellPlatform ])).override { ignoreCollisions = true; };
See d64917ad17
for a long and detailed discussion of why these path collisions may occur.
