From: Eric Bavier <address@hidden>
The first of these patches lets search-path-as-list function correctly
when a
pattern is given and the 'directory file type is specified.
The second adds a native-search-paths field to our ghc package. It
modifies
our haskell-build-system to install a package-specific package database
with
each haskell library. GHC insists on a binary package cache file
called
'package.cache' to be in each directory listed in GHC_PACKAGE PATH, so
we
uniquely name the package database directories, and use a file-pattern
to add
those to GHC_PACKAGE_PATH.
The benefit of this over the current situation is that one gets the
benefit of
`guix package --search-paths`. Currently, after installing ghc
packages, the
user needs to know to manually add
~/.guix-profile/lib/ghc-7.8.4/package.conf.d to their GHC_PACKAGE_PATH.
GHC
package recipes would no longer need to propagate runtime dependencies,
and
'guix environment' also works nicely out-of-the-box::
$ guix environment --ad-hoc ghc ghc-attoparsec
$ ghc-pkg list
/gnu/store/...-ghc-mtl-2.1.3.1/lib/ghc-7.8.4/ghc-mtl-2.1.3.1.conf.d
base-4.7.0.2
ghc-prim-0.3.1.0
integer-gmp-0.5.1.0
mtl-2.1.3.1
rts-1.0
transformers-0.3.0.0
/gnu/store/...-ghc-regex-base-0.93.2/lib/ghc-7.8.4/ghc-regex-base-0.93.2.conf.d
array-0.5.0.0
base-4.7.0.2
bytestring-0.10.4.0
...
/gnu/store/4vvmngz1w8ccm7v7mk4f4dxk45834464-ghc-attoparsec-0.13.0.0/lib/ghc-7.8.4/ghc-attoparsec-0.13.0.0.conf.d
array-0.5.0.0
attoparsec-0.13.0.0
...
Though, as you can see in this example, libraries may be listed more
than
once. As far as I can tell at this point, that is just an aesthetic
detail.
Future work might involve filtering build-only library dependencies
from the
generated package database. We could probably also remove the ghc
package
database creation during profile generation.
I'd be insterested in hearing others' thoughts on this approach.
Eric Bavier (2):
utils: Have search-path-as-list pattern search for directories.
gnu: ghc: Add GHC_PACKAGE_PATH native search path.
gnu/packages/haskell.scm | 6 +++
guix/build/haskell-build-system.scm | 100
+++++++++++++++++++++++++++++-------
guix/build/utils.scm | 9 ++--
guix/search-paths.scm | 6 ---
4 files changed, 93 insertions(+), 28 deletions(-)