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Configuration
=============

Overview
--------

The global configuration file for ``cabal-install`` is
``~/.cabal/config``. If you do not have this file, ``cabal`` will create
it for you on the first call to ``cabal update``. Alternatively, you can
explicitly ask ``cabal`` to create it for you using

    ``cabal user-config update``

Most of the options in this configuration file are also available as
command line arguments, and the corresponding documentation can be used
to lookup their meaning. The created configuration file only specifies
values for a handful of options. Most options are left at their default
value, which it documents; for instance,

::

    -- executable-stripping: True

means that the configuration file currently does not specify a value for
the ``executable-stripping`` option (the line is commented out), and
that the default is ``True``; if you wanted to disable stripping of
executables by default, you would change this line to

::

    executable-stripping: False

You can also use ``cabal user-config update`` to migrate configuration
files created by older versions of ``cabal``.

Repository specification
------------------------

An important part of the configuration if the specification of the
repository. When ``cabal`` creates a default config file, it configures
the repository to be the central Hackage server:

::

    repository hackage.haskell.org
      url: http://hackage.haskell.org/

The name of the repository is given on the first line, and can be
anything; packages downloaded from this repository will be cached under
``~/.cabal/packages/hackage.haskell.org`` (or whatever name you specify;
you can change the prefix by changing the value of
``remote-repo-cache``). If you want, you can configure multiple
repositories, and ``cabal`` will combine them and be able to download
packages from any of them.

Using secure repositories
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^^^^^^^^^^^^^^^^^^^^^^^^^
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For repositories that support the TUF security infrastructure (this
includes Hackage), you can enable secure access to the repository by
specifying:

::

    repository hackage.haskell.org
      url: http://hackage.haskell.org/
      secure: True
      root-keys: <root-key-IDs>
      key-threshold: <key-threshold>

The ``<root-key-IDs>`` and ``<key-threshold>`` values are used for
bootstrapping. As part of the TUF infrastructure the repository will
contain a file ``root.json`` (for instance,
http://hackage.haskell.org/root.json) which the client needs to do
verification. However, how can ``cabal`` verify the ``root.json`` file
*itself*? This is known as bootstrapping: if you specify a list of root
key IDs and a corresponding threshold, ``cabal`` will verify that the
downloaded ``root.json`` file has been signed with at least
``<key-threshold>`` keys from your set of ``<root-key-IDs>``.

You can, but are not recommended to, omit these two fields. In that case
``cabal`` will download the ``root.json`` field and use it without
verification. Although this bootstrapping step is then unsafe, all
subsequent access is secure (provided that the downloaded ``root.json``
was not tempered with). Of course, adding ``root-keys`` and
``key-threshold`` to your repository specification only shifts the
problem, because now you somehow need to make sure that the key IDs you
received were the right ones. How that is done is however outside the
scope of ``cabal`` proper.

More information about the security infrastructure can be found at
https://github.com/well-typed/hackage-security.

Legacy repositories
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^^^^^^^^^^^^^^^^^^^
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Currently ``cabal`` supports two kinds of legacy repositories. The
first is specified using

::

    remote-repo: hackage.haskell.org:http://hackage.haskell.org/packages/archive

This is just syntactic sugar for

::

    repository hackage.haskell.org
      url: hackage.haskell.org:http://hackage.haskell.org/packages/archive

although, in (and only in) the specific case of Hackage, the URL
``http://hackage.haskell.org/packages/archive`` will be silently
translated to ``http://hackage.haskell.org/``.

The second kind of legacy repositories are so-called local
repositories:

::

    local-repo: my-local-repo:/path/to/local/repo

This can be used to access repositories on the local file system.
However, the layout of these local repositories is different from the
layout of remote repositories, and usage of these local repositories is
deprecated.

Secure local repositories
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^^^^^^^^^^^^^^^^^^^^^^^^^
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If you want to use repositories on your local file system, it is
recommended instead to use a *secure* local repository:

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.. code-block:: none
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    repository my-local-repo
      url: file:/path/to/local/repo
      secure: True
      root-keys: <root-key-IDs>
      key-threshold: <key-threshold>

The layout of these secure local repos matches the layout of remote
repositories exactly; the
`hackage-repo-tool <http://hackage.haskell.org/package/hackage-repo-tool>`__
can be used to create and manage such repositories.

Building and installing packages
================================

After you've unpacked a Cabal package, you can build it by moving into
the root directory of the package and running the ``cabal`` tool there:

    ``cabal [command] [option...]``

The *command* argument selects a particular step in the build/install
process.

You can also get a summary of the command syntax with

    ``cabal help``

Alternatively, you can also use the ``Setup.hs`` or ``Setup.lhs``
script:

    ``runhaskell Setup.hs [command] [option...]``

For the summary of the command syntax, run:

    ``cabal help``

or

    ``runhaskell Setup.hs --help``

Building and installing a system package
----------------------------------------

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.. code-block:: bash
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    runhaskell Setup.hs configure --ghc
    runhaskell Setup.hs build
    runhaskell Setup.hs install

The first line readies the system to build the tool using GHC; for
example, it checks that GHC exists on the system. The second line
performs the actual building, while the last both copies the build
results to some permanent place and registers the package with GHC.

Building and installing a user package
--------------------------------------

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.. code-block:: bash
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    runhaskell Setup.hs configure --user
    runhaskell Setup.hs build
    runhaskell Setup.hs install

The package is installed under the user's home directory and is
registered in the user's package database (``--user``).

Installing packages from Hackage
--------------------------------

The ``cabal`` tool also can download, configure, build and install a
`Hackage <http://hackage.haskell.org/>`__ package and all of its
dependencies in a single step. To do this, run:

::

    cabal install [PACKAGE...]

To browse the list of available packages, visit the
`Hackage <http://hackage.haskell.org/>`__ web site.

Developing with sandboxes
-------------------------

By default, any dependencies of the package are installed into the
global or user package databases (e.g. using
``cabal install --only-dependencies``). If you're building several
different packages that have incompatible dependencies, this can cause
the build to fail. One way to avoid this problem is to build each
package in an isolated environment ("sandbox"), with a sandbox-local
package database. Because sandboxes are per-project, inconsistent
dependencies can be simply disallowed.

For more on sandboxes, see also `this
article <http://coldwa.st/e/blog/2013-08-20-Cabal-sandbox.html>`__.

Sandboxes: basic usage
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^^^^^^^^^^^^^^^^^^^^^^
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To initialise a fresh sandbox in the current directory, run
``cabal sandbox init``. All subsequent commands (such as ``build`` and
``install``) from this point will use the sandbox.

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.. code-block:: bash
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    $ cd /path/to/my/haskell/library
    $ cabal sandbox init                   # Initialise the sandbox
    $ cabal install --only-dependencies    # Install dependencies into the sandbox
    $ cabal build                          # Build your package inside the sandbox

It can be useful to make a source package available for installation in
the sandbox - for example, if your package depends on a patched or an
unreleased version of a library. This can be done with the
``cabal sandbox add-source`` command - think of it as "local
`Hackage <http://hackage.haskell.org/>`__". If an add-source dependency
is later modified, it is reinstalled automatically.

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.. code-block:: bash
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    $ cabal sandbox add-source /my/patched/library # Add a new add-source dependency
    $ cabal install --dependencies-only            # Install it into the sandbox
    $ cabal build                                  # Build the local package
    $ $EDITOR /my/patched/library/Source.hs        # Modify the add-source dependency
    $ cabal build                                  # Modified dependency is automatically reinstalled

Normally, the sandbox settings (such as optimisation level) are
inherited from the main Cabal config file (``$HOME/cabal/config``).
Sometimes, though, you need to change some settings specifically for a
single sandbox. You can do this by creating a ``cabal.config`` file in
the same directory with your ``cabal.sandbox.config`` (which was created
by ``sandbox init``). This file has the same syntax as the main Cabal
config file.

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.. code-block:: console
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    $ cat cabal.config
    documentation: True
    constraints: foo == 1.0, bar >= 2.0, baz
    $ cabal build                                  # Uses settings from the cabal.config file

When you have decided that you no longer want to build your package
inside a sandbox, just delete it:

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.. code-block:: bash
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    $ cabal sandbox delete                       # Built-in command
    $ rm -rf .cabal-sandbox cabal.sandbox.config # Alternative manual method

Sandboxes: advanced usage
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^^^^^^^^^^^^^^^^^^^^^^^^^
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The default behaviour of the ``add-source`` command is to track
modifications done to the added dependency and reinstall the sandbox
copy of the package when needed. Sometimes this is not desirable: in
these cases you can use ``add-source --snapshot``, which disables the
change tracking. In addition to ``add-source``, there are also
``list-sources`` and ``delete-source`` commands.

Sometimes one wants to share a single sandbox between multiple packages.
This can be easily done with the ``--sandbox`` option:

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.. code-block:: bash
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    $ mkdir -p /path/to/shared-sandbox
    $ cd /path/to/shared-sandbox
    $ cabal sandbox init --sandbox .
    $ cd /path/to/package-a
    $ cabal sandbox init --sandbox /path/to/shared-sandbox
    $ cd /path/to/package-b
    $ cabal sandbox init --sandbox /path/to/shared-sandbox

Note that ``cabal sandbox init --sandbox .`` puts all sandbox files into
the current directory. By default, ``cabal sandbox init`` initialises a
new sandbox in a newly-created subdirectory of the current working
directory (``./.cabal-sandbox``).

Using multiple different compiler versions simultaneously is also
supported, via the ``-w`` option:

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.. code-block:: bash
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    $ cabal sandbox init
    $ cabal install --only-dependencies -w /path/to/ghc-1 # Install dependencies for both compilers
    $ cabal install --only-dependencies -w /path/to/ghc-2
    $ cabal configure -w /path/to/ghc-1                   # Build with the first compiler
    $ cabal build
    $ cabal configure -w /path/to/ghc-2                   # Build with the second compiler
    $ cabal build

It can be occasionally useful to run the compiler-specific package
manager tool (e.g. ``ghc-pkg``) tool on the sandbox package DB directly
(for example, you may need to unregister some packages). The
``cabal sandbox hc-pkg`` command is a convenient wrapper that runs the
compiler-specific package manager tool with the arguments:

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.. code-block:: console
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    $ cabal -v sandbox hc-pkg list
    Using a sandbox located at /path/to/.cabal-sandbox
    'ghc-pkg' '--global' '--no-user-package-conf'
        '--package-conf=/path/to/.cabal-sandbox/i386-linux-ghc-7.4.2-packages.conf.d'
        'list'
    [...]

The ``--require-sandbox`` option makes all sandbox-aware commands
(``install``/``build``/etc.) exit with error if there is no sandbox
present. This makes it harder to accidentally modify the user package
database. The option can be also turned on via the per-user
configuration file (``~/.cabal/config``) or the per-project one
(``$PROJECT_DIR/cabal.config``). The error can be squelched with
``--no-require-sandbox``.

The option ``--sandbox-config-file`` allows to specify the location of
the ``cabal.sandbox.config`` file (by default, ``cabal`` searches for it
in the current directory). This provides the same functionality as
shared sandboxes, but sometimes can be more convenient. Example:

::

    $ mkdir my/sandbox
    $ cd my/sandbox
    $ cabal sandbox init
    $ cd /path/to/my/project
    $ cabal --sandbox-config-file=/path/to/my/sandbox/cabal.sandbox.config install
    # Uses the sandbox located at /path/to/my/sandbox/.cabal-sandbox
    $ cd ~
    $ cabal --sandbox-config-file=/path/to/my/sandbox/cabal.sandbox.config install
    # Still uses the same sandbox

The sandbox config file can be also specified via the
``CABAL_SANDBOX_CONFIG`` environment variable.

Finally, the flag ``--ignore-sandbox`` lets you temporarily ignore an
existing sandbox:

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.. code-block:: bash
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    $ mkdir my/sandbox
    $ cd my/sandbox
    $ cabal sandbox init
    $ cabal --ignore-sandbox install text
    # Installs 'text' in the user package database ('~/.cabal').

Creating a binary package
-------------------------

When creating binary packages (e.g. for Red Hat or Debian) one needs to
create a tarball that can be sent to another system for unpacking in the
root directory:

::

    runhaskell Setup.hs configure --prefix=/usr
    runhaskell Setup.hs build
    runhaskell Setup.hs copy --destdir=/tmp/mypkg
    tar -czf mypkg.tar.gz /tmp/mypkg/

If the package contains a library, you need two additional steps:

::

    runhaskell Setup.hs register --gen-script
    runhaskell Setup.hs unregister --gen-script

This creates shell scripts ``register.sh`` and ``unregister.sh``, which
must also be sent to the target system. After unpacking there, the
package must be registered by running the ``register.sh`` script. The
``unregister.sh`` script would be used in the uninstall procedure of the
package. Similar steps may be used for creating binary packages for
Windows.

The following options are understood by all commands:

``--help``, ``-h`` or ``-?``
    List the available options for the command.
``--verbose=``\ *n* or ``-v``\ *n*
    Set the verbosity level (0-3). The normal level is 1; a missing *n*
    defaults to 2.

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    There is also an extended version of this command which can be
    used to fine-tune the verbosity of output.  It takes the
    form ``[silent|normal|verbose|debug]``\ *flags*, where *flags*
    is a list of ``+`` flags which toggle various aspects of
    output.  At the moment, only ``+callsite`` and ``+callstack``
    are supported, which respectively toggle call site and call
    stack printing (these are only supported if Cabal
    is built with a sufficiently recent GHC.)

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The various commands and the additional options they support are
described below. In the simple build infrastructure, any other options
will be reported as errors.

setup configure
---------------

Prepare to build the package. Typically, this step checks that the
target platform is capable of building the package, and discovers
platform-specific features that are needed during the build.

The user may also adjust the behaviour of later stages using the options
listed in the following subsections. In the simple build infrastructure,
the values supplied via these options are recorded in a private file
read by later stages.

If a user-supplied ``configure`` script is run (see the section on
`system-dependent
parameters <developing-packages.html#system-dependent-parameters>`__ or
on `complex
packages <developing-packages.html#more-complex-packages>`__), it is
passed the ``--with-hc-pkg``, ``--prefix``, ``--bindir``, ``--libdir``,
``--datadir``, ``--libexecdir`` and ``--sysconfdir`` options. In
addition the value of the ``--with-compiler`` option is passed in a
``--with-hc`` option and all options specified with
``--configure-option=`` are passed on.

In Cabal 2.0, support for a single positional argument was added to
``setup configure`` This makes Cabal configure a the specific component
to be configured. Specified names can be qualified with ``lib:`` or
``exe:`` in case just a name is ambiguous (as would be the case for a
package named ``p`` which has a library and an executable named ``p``.)
This has the following effects:

-  Subsequent invocations of ``build``, ``register``, etc. operate only
   on the configured component.

-  Cabal requires all "internal" dependencies (e.g., an executable
   depending on a library defined in the same package) must be found in
   the set of databases via ``--package-db`` (and related flags): these
   dependencies are assumed to be up-to-date. A dependency can be
   explicitly specified using ``--dependency`` simply by giving the name
   of the internal library; e.g., the dependency for an internal library
   named ``foo`` is given as
   ``--dependency=pkg-internal=pkg-1.0-internal-abcd``.

-  Only the dependencies needed for the requested component are
   required. Similarly, when ``--exact-configuration`` is specified,
   it's only necessary to specify ``--dependency`` for the component.
   (As mentioned previously, you *must* specify internal dependencies as
   well.)

-  Internal ``build-tools`` dependencies are expected to be in the
   ``PATH`` upon subsequent invocations of ``setup``.

Full details can be found in the `Componentized Cabal
proposal <https://github.com/ezyang/ghc-proposals/blob/master/proposals/0000-componentized-cabal.rst>`__.

Programs used for building
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^^^^^^^^^^^^^^^^^^^^^^^^^^
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The following options govern the programs used to process the source
files of a package:

``--ghc`` or ``-g``, ``--jhc``, ``--lhc``, ``--uhc``
    Specify which Haskell implementation to use to build the package. At
    most one of these flags may be given. If none is given, the
    implementation under which the setup script was compiled or
    interpreted is used.
``--with-compiler=``\ *path* or ``-w``\ *path*
    Specify the path to a particular compiler. If given, this must match
    the implementation selected above. The default is to search for the
    usual name of the selected implementation.

    This flag also sets the default value of the ``--with-hc-pkg``
    option to the package tool for this compiler. Check the output of
    ``setup configure -v`` to ensure that it finds the right package
    tool (or use ``--with-hc-pkg`` explicitly).

``--with-hc-pkg=``\ *path*
    Specify the path to the package tool, e.g. ``ghc-pkg``. The package
    tool must be compatible with the compiler specified by
    ``--with-compiler``. If this option is omitted, the default value is
    determined from the compiler selected.
``--with-``\ *``prog``*\ ``=``\ *path*
    Specify the path to the program *prog*. Any program known to Cabal
    can be used in place of *prog*. It can either be a fully path or the
    name of a program that can be found on the program search path. For
    example: ``--with-ghc=ghc-6.6.1`` or
    ``--with-cpphs=/usr/local/bin/cpphs``. The full list of accepted
    programs is not enumerated in this user guide. Rather, run
    ``cabal install --help`` to view the list.
``--``\ *``prog``*\ ``-options=``\ *options*
    Specify additional options to the program *prog*. Any program known
    to Cabal can be used in place of *prog*. For example:
    ``--alex-options="--template=mytemplatedir/"``. The *options* is
    split into program options based on spaces. Any options containing
    embedded spaced need to be quoted, for example
    ``--foo-options='--bar="C:\Program File\Bar"'``. As an alternative
    that takes only one option at a time but avoids the need to quote,
    use ``--``\ *``prog``*\ ``-option`` instead.
``--``\ *``prog``*\ ``-option=``\ *option*
    Specify a single additional option to the program *prog*. For
    passing an option that contain embedded spaces, such as a file name
    with embedded spaces, using this rather than
    ``--``\ *``prog``*\ ``-options`` means you do not need an additional
    level of quoting. Of course if you are using a command shell you may
    still need to quote, for example
    ``--foo-options="--bar=C:\Program File\Bar"``.

All of the options passed with either ``--``\ *``prog``*\ ``-options``
or ``--``\ *``prog``*\ ``-option`` are passed in the order they were
specified on the configure command line.

Installation paths
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^^^^^^^^^^^^^^^^^^
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The following options govern the location of installed files from a
package:

``--prefix=``\ *dir*
    The root of the installation. For example for a global install you
    might use ``/usr/local`` on a Unix system, or ``C:\Program Files``
    on a Windows system. The other installation paths are usually
    subdirectories of *prefix*, but they don't have to be.

    In the simple build system, *dir* may contain the following path
    variables: ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``,
    ``$os``, ``$arch``, ``$abi``, ``$abitag``

``--bindir=``\ *dir*
    Executables that the user might invoke are installed here.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$pkgid``, ``$pkg``, ``$version``,
    ``$compiler``, ``$os``, ``$arch``, ``$abi``, \`$abitag

``--libdir=``\ *dir*
    Object-code libraries are installed here.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$pkgid``, ``$pkg``,
    ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

``--libexecdir=``\ *dir*
    Executables that are not expected to be invoked directly by the user
    are installed here.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$libdir``, ``$libsubdir``,
    ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``, ``$os``,
    ``$arch``, ``$abi``, ``$abitag``

``--datadir``\ =\ *dir*
    Architecture-independent data files are installed here.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$libdir``, ``$libsubdir``,
    ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``, ``$os``,
    ``$arch``, ``$abi``, ``$abitag``

``--sysconfdir=``\ *dir*
    Installation directory for the configuration files.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$libdir``, ``$libsubdir``,
    ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``, ``$os``,
    ``$arch``, ``$abi``, ``$abitag``

In addition the simple build system supports the following installation
path options:

``--libsubdir=``\ *dir*
    A subdirectory of *libdir* in which libraries are actually
    installed. For example, in the simple build system on Unix, the
    default *libdir* is ``/usr/local/lib``, and *libsubdir* contains the
    package identifier and compiler, e.g. ``mypkg-0.2/ghc-6.4``, so
    libraries would be installed in
    ``/usr/local/lib/mypkg-0.2/ghc-6.4``.

    *dir* may contain the following path variables: ``$pkgid``,
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

``--datasubdir=``\ *dir*
    A subdirectory of *datadir* in which data files are actually
    installed.

    *dir* may contain the following path variables: ``$pkgid``,
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

``--docdir=``\ *dir*
    Documentation files are installed relative to this directory.

    *dir* may contain the following path variables: ``$prefix``,
    ``$bindir``, ``$libdir``, ``$libsubdir``, ``$datadir``,
    ``$datasubdir``, ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``,
    ``$os``, ``$arch``, ``$abi``, ``$abitag``

``--htmldir=``\ *dir*
    HTML documentation files are installed relative to this directory.

    *dir* may contain the following path variables: ``$prefix``,
    ``$bindir``, ``$libdir``, ``$libsubdir``, ``$datadir``,
    ``$datasubdir``, ``$docdir``, ``$pkgid``, ``$pkg``, ``$version``,
    ``$compiler``, ``$os``, ``$arch``, ``$abi``, ``$abitag``

``--program-prefix=``\ *prefix*
    Prepend *prefix* to installed program names.

    *prefix* may contain the following path variables: ``$pkgid``,
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

``--program-suffix=``\ *suffix*
    Append *suffix* to installed program names. The most obvious use for
    this is to append the program's version number to make it possible
    to install several versions of a program at once:
    ``--program-suffix='$version'``.

    *suffix* may contain the following path variables: ``$pkgid``,
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

Path variables in the simple build system
648
"""""""""""""""""""""""""""""""""""""""""
649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700

For the simple build system, there are a number of variables that can be
used when specifying installation paths. The defaults are also specified
in terms of these variables. A number of the variables are actually for
other paths, like ``$prefix``. This allows paths to be specified
relative to each other rather than as absolute paths, which is important
for building relocatable packages (see `prefix
independence <#prefix-independence>`__).

``$prefix``
    The path variable that stands for the root of the installation. For
    an installation to be relocatable, all other installation paths must
    be relative to the ``$prefix`` variable.
``$bindir``
    The path variable that expands to the path given by the ``--bindir``
    configure option (or the default).
``$libdir``
    As above but for ``--libdir``
``$libsubdir``
    As above but for ``--libsubdir``
``$datadir``
    As above but for ``--datadir``
``$datasubdir``
    As above but for ``--datasubdir``
``$docdir``
    As above but for ``--docdir``
``$pkgid``
    The name and version of the package, e.g. ``mypkg-0.2``
``$pkg``
    The name of the package, e.g. ``mypkg``
``$version``
    The version of the package, e.g. ``0.2``
``$compiler``
    The compiler being used to build the package, e.g. ``ghc-6.6.1``
``$os``
    The operating system of the computer being used to build the
    package, e.g. ``linux``, ``windows``, ``osx``, ``freebsd`` or
    ``solaris``
``$arch``
    The architecture of the computer being used to build the package,
    e.g. ``i386``, ``x86_64``, ``ppc`` or ``sparc``
``$abitag``
    An optional tag that a compiler can use for telling incompatible
    ABI's on the same architecture apart. GHCJS encodes the underlying
    GHC version in the ABI tag.
``$abi``
    A shortcut for getting a path that completely identifies the
    platform in terms of binary compatibility. Expands to the same value
    as ``$arch-$os-compiler-$abitag`` if the compiler uses an abi tag,
    ``$arch-$os-$compiler`` if it doesn't.

Paths in the simple build system
701
""""""""""""""""""""""""""""""""
702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737

For the simple build system, the following defaults apply:

+------------------------------+-------------------------------------------------------------+---------------------------+
| Option                       | Windows Default                                             | Unix Default              |
+==============================+=============================================================+===========================+
| ``--prefix`` (global)        | ``C:\Program Files\Haskell``                                | ``/usr/local``            |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--prefix`` (per-user)      | ``C:\Documents And Settings\user\Application Data\cabal``   | ``$HOME/.cabal``          |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--bindir``                 | ``$prefix\bin``                                             | ``$prefix/bin``           |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--libdir``                 | ``$prefix``                                                 | ``$prefix/lib``           |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--libsubdir`` (others)     | ``$pkgid\$compiler``                                        | ``$pkgid/$compiler``      |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--libexecdir``             | ``$prefix\$pkgid``                                          | ``$prefix/libexec``       |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--datadir`` (executable)   | ``$prefix``                                                 | ``$prefix/share``         |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--datadir`` (library)      | ``C:\Program Files\Haskell``                                | ``$prefix/share``         |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--datasubdir``             | ``$pkgid``                                                  | ``$pkgid``                |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--docdir``                 | ``$prefix\doc\$pkgid``                                      | ``$datadir/doc/$pkgid``   |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--sysconfdir``             | ``$prefix\etc``                                             | ``$prefix/etc``           |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--htmldir``                | ``$docdir\html``                                            | ``$docdir/html``          |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--program-prefix``         | (empty)                                                     | (empty)                   |
+------------------------------+-------------------------------------------------------------+---------------------------+
| ``--program-suffix``         | (empty)                                                     | (empty)                   |
+------------------------------+-------------------------------------------------------------+---------------------------+

Prefix-independence
738
"""""""""""""""""""
739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765

On Windows it is possible to obtain the pathname of the running program.
This means that we can construct an installable executable package that
is independent of its absolute install location. The executable can find
its auxiliary files by finding its own path and knowing the location of
the other files relative to ``$bindir``. Prefix-independence is
particularly useful: it means the user can choose the install location
(i.e. the value of ``$prefix``) at install-time, rather than having to
bake the path into the binary when it is built.

In order to achieve this, we require that for an executable on Windows,
all of ``$bindir``, ``$libdir``, ``$datadir`` and ``$libexecdir`` begin
with ``$prefix``. If this is not the case then the compiled executable
will have baked-in all absolute paths.

The application need do nothing special to achieve prefix-independence.
If it finds any files using ``getDataFileName`` and the `other functions
provided for the
purpose <developing-packages.html#accessing-data-files-from-package-code>`__,
the files will be accessed relative to the location of the current
executable.

A library cannot (currently) be prefix-independent, because it will be
linked into an executable whose file system location bears no relation
to the library package.

Controlling Flag Assignments
766
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785

Flag assignments (see the `resolution of conditions and
flags <developing-packages.html#resolution-of-conditions-and-flags>`__)
can be controlled with the following command line options.

``-f`` *flagname* or ``-f`` ``-``\ *flagname*
    Force the specified flag to ``true`` or ``false`` (if preceded with
    a ``-``). Later specifications for the same flags will override
    earlier, i.e., specifying ``-fdebug -f-debug`` is equivalent to
    ``-f-debug``
``--flags=``\ *flagspecs*
    Same as ``-f``, but allows specifying multiple flag assignments at
    once. The parameter is a space-separated list of flag names (to
    force a flag to ``true``), optionally preceded by a ``-`` (to force
    a flag to ``false``). For example,
    ``--flags="debug -feature1 feature2"`` is equivalent to
    ``-fdebug -f-feature1 -ffeature2``.

Building Test Suites
786
^^^^^^^^^^^^^^^^^^^^
787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806

``--enable-tests``
    Build the test suites defined in the package description file during
    the ``build`` stage. Check for dependencies required by the test
    suites. If the package is configured with this option, it will be
    possible to run the test suites with the ``test`` command after the
    package is built.
``--disable-tests``
    (default) Do not build any test suites during the ``build`` stage.
    Do not check for dependencies required only by the test suites. It
    will not be possible to invoke the ``test`` command without
    reconfiguring the package.
``--enable-coverage``
    Build libraries and executables (including test suites) with Haskell
    Program Coverage enabled. Running the test suites will automatically
    generate coverage reports with HPC.
``--disable-coverage``
    (default) Do not enable Haskell Program Coverage.

Miscellaneous options
807
^^^^^^^^^^^^^^^^^^^^^
808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401

``--user``
    Does a per-user installation. This changes the `default installation
    prefix <#paths-in-the-simple-build-system>`__. It also allow
    dependencies to be satisfied by the user's package database, in
    addition to the global database. This also implies a default of
    ``--user`` for any subsequent ``install`` command, as packages
    registered in the global database should not depend on packages
    registered in a user's database.
``--global``
    (default) Does a global installation. In this case package
    dependencies must be satisfied by the global package database. All
    packages in the user's package database will be ignored. Typically
    the final installation step will require administrative privileges.
``--package-db=``\ *db*
    Allows package dependencies to be satisfied from this additional
    package database *db* in addition to the global package database.
    All packages in the user's package database will be ignored. The
    interpretation of *db* is implementation-specific. Typically it will
    be a file or directory. Not all implementations support arbitrary
    package databases.

    This pushes an extra db onto the db stack. The ``--global`` and
    ``--user`` mode switches add the respective [Global] and [Global,
    User] dbs to the initial stack. There is a compiler-implementation
    constraint that the global db must appear first in the stack, and if
    the user one appears at all, it must appear immediately after the
    global db.

    To reset the stack, use ``--package-db=clear``.

``--ipid=``\ *ipid*
    Specifies the *installed package identifier* of the package to be
    built; this identifier is passed on to GHC and serves as the basis
    for linker symbols and the ``id`` field in a ``ghc-pkg``
    registration. When a package has multiple components, the actual
    component identifiers are derived off of this identifier (e.g., an
    internal library ``foo`` from package ``p-0.1-abcd`` will get the
    identifier ``p-0.1-abcd-foo``.
``--cid=``\ *cid*
    Specifies the *component identifier* of the component being built;
    this is only valid if you are configuring a single component.
``--default-user-config=`` *file*
    Allows a "default" ``cabal.config`` freeze file to be passed in
    manually. This file will only be used if one does not exist in the
    project directory already. Typically, this can be set from the
    global cabal ``config`` file so as to provide a default set of
    partial constraints to be used by projects, providing a way for
    users to peg themselves to stable package collections.
``--enable-optimization``\ [=*n*] or ``-O``\ [*n*]
    (default) Build with optimization flags (if available). This is
    appropriate for production use, taking more time to build faster
    libraries and programs.

    The optional *n* value is the optimisation level. Some compilers
    support multiple optimisation levels. The range is 0 to 2. Level 0
    is equivalent to ``--disable-optimization``, level 1 is the default
    if no *n* parameter is given. Level 2 is higher optimisation if the
    compiler supports it. Level 2 is likely to lead to longer compile
    times and bigger generated code.

``--disable-optimization``
    Build without optimization. This is suited for development: building
    will be quicker, but the resulting library or programs will be
    slower.
``--enable-profiling``
    Build libraries and executables with profiling enabled (for
    compilers that support profiling as a separate mode). For this to
    work, all libraries used by this package must also have been built
    with profiling support. For libraries this involves building an
    additional instance of the library in addition to the normal
    non-profiling instance. For executables it changes the single
    executable to be built in profiling mode.

    This flag covers both libraries and executables, but can be
    overridden by the ``--enable-library-profiling`` flag.

    See also the ``--profiling-detail`` flag below.

``--disable-profiling``
    (default) Do not enable profiling in generated libraries and
    executables.
``--enable-library-profiling`` or ``-p``
    As with ``--enable-profiling`` above, but it applies only for
    libraries. So this generates an additional profiling instance of the
    library in addition to the normal non-profiling instance.

    The ``--enable-profiling`` flag controls the profiling mode for both
    libraries and executables, but if different modes are desired for
    libraries versus executables then use ``--enable-library-profiling``
    as well.

``--disable-library-profiling``
    (default) Do not generate an additional profiling version of the
    library.
``--profiling-detail``\ [=*level*]
    Some compilers that support profiling, notably GHC, can allocate
    costs to different parts of the program and there are different
    levels of granularity or detail with which this can be done. In
    particular for GHC this concept is called "cost centers", and GHC
    can automatically add cost centers, and can do so in different ways.

    This flag covers both libraries and executables, but can be
    overridden by the ``--library-profiling-detail`` flag.

    Currently this setting is ignored for compilers other than GHC. The
    levels that cabal currently supports are:

    ``default``
        For GHC this uses ``exported-functions`` for libraries and
        ``toplevel-functions`` for executables.
    ``none``
        No costs will be assigned to any code within this component.
    ``exported-functions``
        Costs will be assigned at the granularity of all top level
        functions exported from each module. In GHC specifically, this
        is for non-inline functions.
    ``toplevel-functions``
        Costs will be assigned at the granularity of all top level
        functions in each module, whether they are exported from the
        module or not. In GHC specifically, this is for non-inline
        functions.
    ``all-functions``
        Costs will be assigned at the granularity of all functions in
        each module, whether top level or local. In GHC specifically,
        this is for non-inline toplevel or where-bound functions or
        values.

    This flag is new in Cabal-1.24. Prior versions used the equivalent
    of ``none`` above.

``--library-profiling-detail``\ [=*level*]
    As with ``--profiling-detail`` above, but it applies only for
    libraries.

    The level for both libraries and executables is set by the
    ``--profiling-detail`` flag, but if different levels are desired for
    libraries versus executables then use ``--library-profiling-detail``
    as well.

``--enable-library-vanilla``
    (default) Build ordinary libraries (as opposed to profiling
    libraries). This is independent of the
    ``--enable-library-profiling`` option. If you enable both, you get
    both.
``--disable-library-vanilla``
    Do not build ordinary libraries. This is useful in conjunction with
    ``--enable-library-profiling`` to build only profiling libraries,
    rather than profiling and ordinary libraries.
``--enable-library-for-ghci``
    (default) Build libraries suitable for use with GHCi.
``--disable-library-for-ghci``
    Not all platforms support GHCi and indeed on some platforms, trying
    to build GHCi libs fails. In such cases this flag can be used as a
    workaround.
``--enable-split-objs``
    Use the GHC ``-split-objs`` feature when building the library. This
    reduces the final size of the executables that use the library by
    allowing them to link with only the bits that they use rather than
    the entire library. The downside is that building the library takes
    longer and uses considerably more memory.
``--disable-split-objs``
    (default) Do not use the GHC ``-split-objs`` feature. This makes
    building the library quicker but the final executables that use the
    library will be larger.
``--enable-executable-stripping``
    (default) When installing binary executable programs, run the
    ``strip`` program on the binary. This can considerably reduce the
    size of the executable binary file. It does this by removing
    debugging information and symbols. While such extra information is
    useful for debugging C programs with traditional debuggers it is
    rarely helpful for debugging binaries produced by Haskell compilers.

    Not all Haskell implementations generate native binaries. For such
    implementations this option has no effect.

``--disable-executable-stripping``
    Do not strip binary executables during installation. You might want
    to use this option if you need to debug a program using gdb, for
    example if you want to debug the C parts of a program containing
    both Haskell and C code. Another reason is if your are building a
    package for a system which has a policy of managing the stripping
    itself (such as some Linux distributions).
``--enable-shared``
    Build shared library. This implies a separate compiler run to
    generate position independent code as required on most platforms.
``--disable-shared``
    (default) Do not build shared library.
``--enable-executable-dynamic``
    Link executables dynamically. The executable's library dependencies
    should be built as shared objects. This implies ``--enable-shared``
    unless ``--disable-shared`` is explicitly specified.
``--disable-executable-dynamic``
    (default) Link executables statically.
``--configure-option=``\ *str*
    An extra option to an external ``configure`` script, if one is used
    (see the section on `system-dependent
    parameters <developing-packages.html#system-dependent-parameters>`__).
    There can be several of these options.
``--extra-include-dirs``\ [=*dir*]
    An extra directory to search for C header files. You can use this
    flag multiple times to get a list of directories.

    You might need to use this flag if you have standard system header
    files in a non-standard location that is not mentioned in the
    package's ``.cabal`` file. Using this option has the same affect as
    appending the directory *dir* to the ``include-dirs`` field in each
    library and executable in the package's ``.cabal`` file. The
    advantage of course is that you do not have to modify the package at
    all. These extra directories will be used while building the package
    and for libraries it is also saved in the package registration
    information and used when compiling modules that use the library.

``--extra-lib-dirs``\ [=*dir*]
    An extra directory to search for system libraries files. You can use
    this flag multiple times to get a list of directories.
``--extra-framework-dirs``\ [=*dir*]
    An extra directory to search for frameworks (OS X only). You can use
    this flag multiple times to get a list of directories.

    You might need to use this flag if you have standard system
    libraries in a non-standard location that is not mentioned in the
    package's ``.cabal`` file. Using this option has the same affect as
    appending the directory *dir* to the ``extra-lib-dirs`` field in
    each library and executable in the package's ``.cabal`` file. The
    advantage of course is that you do not have to modify the package at
    all. These extra directories will be used while building the package
    and for libraries it is also saved in the package registration
    information and used when compiling modules that use the library.

``--dependency``\ [=*pkgname*\ =\ *ipid*]
    Specify that a particular dependency should used for a particular
    package name. In particular, it declares that any reference to
    *pkgname* in a ``build-depends`` should be resolved to *ipid*.
``--exact-configuration``
    This changes Cabal to require every dependency be explicitly
    specified using ``--dependency``, rather than use Cabal's (very
    simple) dependency solver. This is useful for programmatic use of
    Cabal's API, where you want to error if you didn't specify enough
    ``--dependency`` flags.
``--allow-newer``\ [=*pkgs*], ``--allow-older``\ [=*pkgs*]
    Selectively relax upper or lower bounds in dependencies without
    editing the package description respectively.

    The following description focuses on upper bounds and the
    ``--allow-newer`` flag, but applies analogously to ``--allow-older``
    and lower bounds. ``--allow-newer`` and ``--allow-older`` can be
    used at the same time.

    If you want to install a package A that depends on B >= 1.0 && <
    2.0, but you have the version 2.0 of B installed, you can compile A
    against B 2.0 by using ``cabal install --allow-newer=B A``. This
    works for the whole package index: if A also depends on C that in
    turn depends on B < 2.0, C's dependency on B will be also relaxed.

    Example:

    ::

        $ cd foo
        $ cabal configure
        Resolving dependencies...
        cabal: Could not resolve dependencies:
        [...]
        $ cabal configure --allow-newer
        Resolving dependencies...
        Configuring foo...

    Additional examples:

    ::

        # Relax upper bounds in all dependencies.
        $ cabal install --allow-newer foo

        # Relax upper bounds only in dependencies on bar, baz and quux.
        $ cabal install --allow-newer=bar,baz,quux foo

        # Relax the upper bound on bar and force bar==2.1.
        $ cabal install --allow-newer=bar --constraint="bar==2.1" foo

    It's also possible to limit the scope of ``--allow-newer`` to single
    packages with the ``--allow-newer=scope:dep`` syntax. This means
    that the dependency on ``dep`` will be relaxed only for the package
    ``scope``.

    Example:

    ::

        # Relax upper bound in foo's dependency on base; also relax upper bound in
        # every package's dependency on lens.
        $ cabal install --allow-newer=foo:base,lens

        # Relax upper bounds in foo's dependency on base and bar's dependency
        # on time; also relax the upper bound in the dependency on lens specified by
        # any package.
        $ cabal install --allow-newer=foo:base,lens --allow-newer=bar:time

    Finally, one can enable ``--allow-newer`` permanently by setting
    ``allow-newer: True`` in the ``~/.cabal/config`` file. Enabling
    'allow-newer' selectively is also supported in the config file
    (``allow-newer: foo, bar, baz:base``).

``--constraint=``\ *constraint*
    Restrict solutions involving a package to a given version range. For
    example, ``cabal install --constraint="bar==2.1"`` will only
    consider install plans that do not use ``bar`` at all, or ``bar`` of
    version 2.1.

    As a special case, ``cabal install --constraint="bar -none"``
    prevents ``bar`` from being used at all (``-none`` abbreviates
    ``> 1 && < 1``); ``cabal install --constraint="bar installed"``
    prevents reinstallation of the ``bar`` package;
    ``cabal install --constraint="bar +foo -baz"`` specifies that the
    flag ``foo`` should be turned on and the ``baz`` flag should be
    turned off.

``--preference=``\ *preference*
    Specify a soft constraint on versions of a package. The solver will
    attempt to satisfy these preferences on a "best-effort" basis.

setup build
-----------

Perform any preprocessing or compilation needed to make this package
ready for installation.

This command takes the following options:

--*prog*-options=*options*, --*prog*-option=*option*
    These are mostly the same as the `options configure
    step <#setup-configure>`__. Unlike the options specified at the
    configure step, any program options specified at the build step are
    not persistent but are used for that invocation only. They options
    specified at the build step are in addition not in replacement of
    any options specified at the configure step.

setup haddock
-------------

Build the documentation for the package using
`haddock <http://www.haskell.org/haddock/>`__. By default, only the
documentation for the exposed modules is generated (but see the
``--executables`` and ``--internal`` flags below).

This command takes the following options:

``--hoogle``
    Generate a file ``dist/doc/html/``\ *pkgid*\ ``.txt``, which can be
    converted by `Hoogle <http://www.haskell.org/hoogle/>`__ into a
    database for searching. This is equivalent to running
    `haddock <http://www.haskell.org/haddock/>`__ with the ``--hoogle``
    flag.
``--html-location=``\ *url*
    Specify a template for the location of HTML documentation for
    prerequisite packages. The substitutions (`see
    listing <#paths-in-the-simple-build-system>`__) are applied to the
    template to obtain a location for each package, which will be used
    by hyperlinks in the generated documentation. For example, the
    following command generates links pointing at
    `Hackage <http://hackage.haskell.org/>`__ pages:

        setup haddock
        --html-location='http://hackage.haskell.org/packages/archive/$pkg/latest/doc/html'

    Here the argument is quoted to prevent substitution by the shell. If
    this option is omitted, the location for each package is obtained
    using the package tool (e.g. ``ghc-pkg``).

``--executables``
    Also run `haddock <http://www.haskell.org/haddock/>`__ for the
    modules of all the executable programs. By default
    `haddock <http://www.haskell.org/haddock/>`__ is run only on the
    exported modules.
``--internal``
    Run `haddock <http://www.haskell.org/haddock/>`__ for the all
    modules, including unexposed ones, and make
    `haddock <http://www.haskell.org/haddock/>`__ generate documentation
    for unexported symbols as well.
``--css=``\ *path*
    The argument *path* denotes a CSS file, which is passed to
    `haddock <http://www.haskell.org/haddock/>`__ and used to set the
    style of the generated documentation. This is only needed to
    override the default style that
    `haddock <http://www.haskell.org/haddock/>`__ uses.
``--hyperlink-source``
    Generate `haddock <http://www.haskell.org/haddock/>`__ documentation
    integrated with
    `HsColour <http://www.cs.york.ac.uk/fp/darcs/hscolour/>`__. First,
    `HsColour <http://www.cs.york.ac.uk/fp/darcs/hscolour/>`__ is run to
    generate colourised code. Then
    `haddock <http://www.haskell.org/haddock/>`__ is run to generate
    HTML documentation. Each entity shown in the documentation is linked
    to its definition in the colourised code.
``--hscolour-css=``\ *path*
    The argument *path* denotes a CSS file, which is passed to
    `HsColour <http://www.cs.york.ac.uk/fp/darcs/hscolour/>`__ as in

        runhaskell Setup.hs hscolour --css=*path*

setup hscolour
--------------

Produce colourised code in HTML format using
`HsColour <http://www.cs.york.ac.uk/fp/darcs/hscolour/>`__. Colourised
code for exported modules is put in
``dist/doc/html/``\ *pkgid*\ ``/src``.

This command takes the following options:

``--executables``
    Also run `HsColour <http://www.cs.york.ac.uk/fp/darcs/hscolour/>`__
    on the sources of all executable programs. Colourised code is put in
    ``dist/doc/html/``\ *pkgid*/*executable*\ ``/src``.
``--css=``\ *path*
    Use the given CSS file for the generated HTML files. The CSS file
    defines the colours used to colourise code. Note that this copies
    the given CSS file to the directory with the generated HTML files
    (renamed to ``hscolour.css``) rather than linking to it.

setup install
-------------

Copy the files into the install locations and (for library packages)
register the package with the compiler, i.e. make the modules it
contains available to programs.

The `install locations <#installation-paths>`__ are determined by
options to ``setup configure``.

This command takes the following options:

``--global``
    Register this package in the system-wide database. (This is the
    default, unless the ``--user`` option was supplied to the
    ``configure`` command.)
``--user``
    Register this package in the user's local package database. (This is
    the default if the ``--user`` option was supplied to the
    ``configure`` command.)

setup copy
----------

Copy the files without registering them. This command is mainly of use
to those creating binary packages.

This command takes the following option:

``--destdir=``\ *path*

Specify the directory under which to place installed files. If this is
not given, then the root directory is assumed.

setup register
--------------

Register this package with the compiler, i.e. make the modules it
contains available to programs. This only makes sense for library
packages. Note that the ``install`` command incorporates this action.
The main use of this separate command is in the post-installation step
for a binary package.

This command takes the following options:

``--global``
    Register this package in the system-wide database. (This is the
    default.)
``--user``
    Register this package in the user's local package database.
``--gen-script``
    Instead of registering the package, generate a script containing
    commands to perform the registration. On Unix, this file is called
    ``register.sh``, on Windows, ``register.bat``. This script might be
    included in a binary bundle, to be run after the bundle is unpacked
    on the target system.
``--gen-pkg-config``\ [=*path*]
    Instead of registering the package, generate a package registration
    file (or directory, in some circumstances). This only applies to
    compilers that support package registration files which at the
    moment is only GHC. The file should be used with the compiler's
    mechanism for registering packages. This option is mainly intended
    for packaging systems. If possible use the ``--gen-script`` option
    instead since it is more portable across Haskell implementations.
    The *path* is optional and can be used to specify a particular
    output file to generate. Otherwise, by default the file is the
    package name and version with a ``.conf`` extension.

    This option outputs a directory if the package requires multiple
    registrations: this can occur if internal/convenience libraries are
    used. These configuration file names are sorted so that they can be
    registered in order.

``--inplace``
    Registers the package for use directly from the build tree, without
    needing to install it. This can be useful for testing: there's no
    need to install the package after modifying it, just recompile and
    test.

    This flag does not create a build-tree-local package database. It
    still registers the package in one of the user or global databases.

    However, there are some caveats. It only works with GHC (currently).
    It only works if your package doesn't depend on having any
    supplemental files installed --- plain Haskell libraries should be
    fine.

setup unregister
----------------

Deregister this package with the compiler.

This command takes the following options:

``--global``
    Deregister this package in the system-wide database. (This is the
    default.)
``--user``
    Deregister this package in the user's local package database.
``--gen-script``
    Instead of deregistering the package, generate a script containing
    commands to perform the deregistration. On Unix, this file is called
    ``unregister.sh``, on Windows, ``unregister.bat``. This script might
    be included in a binary bundle, to be run on the target system.

setup clean
-----------

Remove any local files created during the ``configure``, ``build``,
``haddock``, ``register`` or ``unregister`` steps, and also any files
and directories listed in the ``extra-tmp-files`` field.

This command takes the following options:

``--save-configure`` or ``-s``
    Keeps the configuration information so it is not necessary to run
    the configure step again before building.

setup test
----------

Run the test suites specified in the package description file. Aside
from the following flags, Cabal accepts the name of one or more test
suites on the command line after ``test``. When supplied, Cabal will run
only the named test suites, otherwise, Cabal will run all test suites in
the package.

``--builddir=``\ *dir*
    The directory where Cabal puts generated build files (default:
    ``dist``). Test logs will be located in the ``test`` subdirectory.
``--human-log=``\ *path*
    The template used to name human-readable test logs; the path is
    relative to ``dist/test``. By default, logs are named according to
    the template ``$pkgid-$test-suite.log``, so that each test suite
    will be logged to its own human-readable log file. Template
    variables allowed are: ``$pkgid``, ``$compiler``, ``$os``,
    ``$arch``, ``$abi``, ``$abitag``, ``$test-suite``, and ``$result``.
``--machine-log=``\ *path*
    The path to the machine-readable log, relative to ``dist/test``. The
    default template is ``$pkgid.log``. Template variables allowed are:
    ``$pkgid``, ``$compiler``, ``$os``, ``$arch``, ``$abi``, ``$abitag``
    and ``$result``.
``--show-details=``\ *filter*
    Determines if the results of individual test cases are shown on the
    terminal. May be ``always`` (always show), ``never`` (never show),
    ``failures`` (show only failed results), or ``streaming`` (show all
    results in real time).
``--test-options=``\ *options*
    Give extra options to the test executables.
``--test-option=``\ *option*
    give an extra option to the test executables. There is no need to
    quote options containing spaces because a single option is assumed,
    so options will not be split on spaces.

setup sdist
-----------

Create a system- and compiler-independent source distribution in a file
*package*-*version*\ ``.tar.gz`` in the ``dist`` subdirectory, for
distribution to package builders. When unpacked, the commands listed in
this section will be available.

The files placed in this distribution are the package description file,
the setup script, the sources of the modules named in the package
description file, and files named in the ``license-file``, ``main-is``,
``c-sources``, ``js-sources``, ``data-files``, ``extra-source-files``
and ``extra-doc-files`` fields.

This command takes the following option:

``--snapshot``
    Append today's date (in "YYYYMMDD" format) to the version number for
    the generated source package. The original package is unaffected.