Simon Marlow wrote:

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It would be nice if ghc-pkg had options to display the value of $libdir or at least the given conf file. [...]

I had *major* pains with this for the upcoming HOpenGL release, too. :-P

Well, I must admit we didn't anticipate that folk would actually want to know what the value of $libdir was - indeed the whole point of the exercise was to abstract away from the actual value so that you could install a GHC tree wherever you like and just change one thing, $libdir (this was part of making the installation process more painless on Windows). On Windows, the value of $libdir is (I believe) not even stored anywhere - it is derived from the location of the ghc.exe binary.

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'ghc -v' will tell you the location of package.conf, which for a normal GHC install is located in $libdir. Does that help?

Ooops, never noticed that. Since when (GHC x.y) has this been working?

Since 5.00, I think.

Is this the "official" way?

Well, there isn't really an official way, but we'll continue to output this as part of ghc -v if that would help.

IMHO it's quite important, because due to the heavy inter-module optimizations, packages are closely tied to a specific GHC version, so $libdir is the only sensible place for package installation.

I don't think I agree that external packages should be installed in GHC's $libdir - by all means include the GHC version in the directory name, but I don't see the need to actually place the files in GHC's installation area. Cheers, Simon