NAME

       ghc-pkg - GHC Haskell Cabal package manager

SYNOPSIS

       ghc-pkg action [OPTION]...

DESCRIPTION

       A  package  is  a  library  of  Haskell modules known to the compiler.  The ghc-pkg tool allows adding or
       removing them from a package database. By default, the system-wide  package  database  is  modified,  but
       alternatively the user's local package database or another specified file can be used.

       To  make  a  package  available for ghc, ghc-pkg can be used to register it.  Unregistering it removes it
       from the database.  Also, packages can be hidden, to make ghc ignore  the  package  by  default,  without
       uninstalling it.  Exposing a package makes a hidden package available.  Additionally, ghc-pkg has various
       commands to query the package database.

       Where a package name is required, the package can be named in full including  the  version  number  (e.g.
       network-1.0),  or  without  the  version  number. Naming a package without the version number matches all
       versions of the package; the specified action will be applied to all the  matching  packages.  A  package
       specifier  that  matches  all  version  of the package can also be written pkg-*, to make it clearer that
       multiple packages are being matched.

ACTIONS

       register filename|-
              Register the package using the specified installed package description.

       update filename|-
              Register the package, overwriting any other package with the same name.

       unregister pkg-id
              Unregister the specified package.

       expose pkg-id
              Expose the specified package.

       hide pkg-id
              Hide the specified package

       list [pkg]...
              List registered packages in the global database, and also the user database if --user is given. If
              a  package  name  is given all the registered versions will be listed in ascending order.  Accepts
              the --simple-output flag.

       dot    Generate a graph of the package dependencies in a form suitable for input for the graphviz  tools.
              For example, to generate a PDF of the dependency graph:
                  dot  tred  dot -Tpdf >pkgs.pdf

       find-module module
              List registered packages exposing module module in the global database, and also the user database
              if --user is given. All the registered versions will be listed in ascending  order.   Accepts  the
              --simple-output flag.

       latest pkg-id
              Prints the highest registered version of a package.

       check  Check  the  consistency  of  package dependencies and list broken packages.  Accepts the --simple-
              output flag.

       describe pkg
              Give the registered description  for  the  specified  package.  The  description  is  returned  in
              precisely the syntax required by ghc-pkg register.

       field pkg field
              Extract  the specified field of the package description for the specified package.  Accepts comma-
              separated multiple fields.

       dump   Dump the registered description for every package. This is like ghc-pkg describe '*', expect  that
              it is intended to be used by tools that parse the results, rather than humans.

       recache
              Regenerate  the  package  database  cache.   This  command should only be necessary if you added a
              package to the database by dropping a file into the database directory manyally.  By default,  the
              global DB is recached; to recache a different DB use --user or --package-conf as appropriate.

OPTIONS

       When  asked  to  modify  a database (register, unregister, update, hide, expose, and also check), ghc-pkg
       modifies the global database by default.  Specifying --user causes it to act on  the  user  database,  or
       --package-conf can be used to act on another database entirely. When multiple of these options are given,
       the rightmost one is used as the database to act upon.

       Commands that query the package database (list, latest, describe, field) operate on the list of databases
       specified  by  the  flags  --user, --global,  and  --package-conf.  If none of these flags are given, the
       default is --global --user.

       --user Use the current user's package database.

       --global
              Use the global package database.

       -f FILE, --package-conf=FILE
              Use the specified package config file.

       --global-conf=FILE
              Location of the global package config.

       --force
              Ignore missing dependencies, directories, and libraries.

       --force-files
              Ignore missing directories and libraries only.

       -g, --auto-ghc-libs
              Automatically build libs for GHCi (with register).

       -?, --help
              Display a help message and exit.

       -V, --version
              Output version information and exit.

       --simple-output
              Print output in easy-to-parse format for some commands.

       --names-only
              Only print package names, not versions; can only be used with list --simple-output.

       --ignore-case
              Ignore case for substring matching.

ENVIRONMENT VARIABLES

       GHC_PACKAGE_PATH
              The GHC_PACKAGE_PATH environment variable may be set to a :-separated  list  of  files  containing
              package  databases.  This  list  of  package  databases  is  used by ghc and ghc-pkg, with earlier
              databases in the list overriding later ones. This order was chosen to match the behaviour  of  the
              PATH  environment  variable; think of it as a list of package databases that are searched left-to-
              right for packages.

              If GHC_PACKAGE_PATH ends in a separator, then the default user and system  package  databases  are
              appended,  in  that  order. e.g. to augment the usual set of packages with a database of your own,
              you could say:

                   export GHC_PACKAGE_PATH=$HOME/.my-ghc-packages.conf:

              To check whether your GHC_PACKAGE_PATH setting is doing the right thing, ghc-pkg  list  will  list
              all the databases in use, in the reverse order they are searched.

FILES

       Both  of  these  locations are changed for Debian.  Upstream still keeps these under /usr.  Some programs
       may refer to that, but look in /var instead.

       /var/lib/ghc/package.conf
              Global package.conf file.

       /var/lib/ghc/package.conf.d/
              Directory for library specific package.conf files.  These are added to the global registry.

SEE ALSO

       ghc(1), runghc(1), hugs(1).

AUTHOR

       This manual page was written by Kari Pahula <kaol@debian.org>, for the Debian project (and may be used by
       others).

                                                   2010-01-27                                         ghc-pkg(1)