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Next Steps
==========
Once your current application is using ``cmd2``, you can start to expand the
functionality by levering other ``cmd2`` features. The three ideas here will
get you started. Browse the rest of the :ref:`features/index:Features` to see
what else ``cmd2`` can help you do.
Argument Parsing
----------------
For all but the simplest of commands, it's probably easier to use `argparse
<https://docs.python.org/3/library/argparse.html>`_ to parse user input.
``cmd2`` provides a ``@with_argparser()`` decorator which associates an
``ArgumentParser`` object with one of your commands. Using this method will:
1. Pass your command a `Namespace <https://docs.python.org/3/library/argparse.html#argparse.Namespace>`_
containing the arguments instead of a string of text.
2. Properly handle quoted string input from your users.
3. Create a help message for you based on the ``ArgumentParser``.
4. Give you a big headstart adding :ref:`features/completion:Completion` to
your application.
5. Make it much easier to implement subcommands (i.e. ``git`` has
a bunch of subcommands such as ``git pull``, ``git diff``, etc).
There's a lot more about :ref:`features/argument_processing:Argument
Processing` if you want to dig in further.
Help
----
If you have lot of commands in your application, ``cmd2`` can categorize those
commands using a one line decorator ``@with_category()``. When a user types
``help`` the available commands will be organized by the category you
specified.
If you were already using ``argparse`` or decided to switch to it, you can
easily :ref:`standardize all of your help messages
<features/argument_processing:Help Messages>` to be generated by your argument
parsers and displayed by ``cmd2``. No more help messages that don't match what
the code actually does.
Generating Output
-----------------
If your program generates output by printing directly to ``sys.stdout``, you
should consider switching to :meth:`~cmd2.Cmd.poutput`,
:meth:`~cmd2.Cmd.perror`, and :meth:`~cmd2.Cmd.pfeedback`. These
methods work with several of the built in :ref:`features/settings:Settings` to
allow the user to view or suppress feedback (i.e. progress or status output).
They also properly handle ansi colored output according to user preference.
Speaking of colored output, you can use any color library you want, or use the
included :meth:`cmd2.ansi.style` function. These and other related topics are
covered in :ref:`features/generating_output:Generating Output`.
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