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> Hello Michele,
>
> Thank you for your proposals. I'll talk with Kendall and Peter about
> all of your proposals but we would
> definitely be interested in an article on the optparse module.
>
> What I would need from you is the introduction (for our planning and
> our work on the next table of contents)
> and an estimated date when you could get a first draft to us.
>
> Regards,
>
> Mark
Okay, here is the introduction. For what concerns the draft, I can work
on it over the weekend and send it to you on Monday. It is not a big
job since I already have some notes for a recipe I planned to submit
to the Python Cookbook and I can expand on that. I don't know how
long it will be at the end, but I would try to make it more or less the
size of a DeveloperWorks paper, i.e. 2500 words.
Please let me know if this is too much or too little. Also, if everything
is approved, let me know about the compensation and the needed paperwork.
Best regards,
Michele
P.S. I will send you the draft in reStructuredText format, if it is
okay for you.
-----------------------------------------------------------------------
The optparse module: writing command line tools the easy way
=======================================================================
"The optparse module is a powerful, flexible, extensible, easy-to-use
command-line parsing library for Python. Using optparse, you can add
intelligent, sophisticated handling of command-line options to your
scripts with very little overhead." -- Greg Ward, optparse author
Introduction
-----------------------------------------------------------------------
Once upon a time, when graphic interfaces were still to be dreamed
about, command line tools were the body and the soul of all programming
tools. Many years have passed since then, but some things have not changed:
command line tools are still fast, efficient, portable, easy to use
and - more importantly - reliable. You can count on them.
You can expect command line scripts to work in any situation,
during the installation phase, in a situation of disaster recovery, when
your window manager breaks down and even in systems with memory
constraints such as embedded devices. When you really need them, command
line tools are always there.
Hence, it is important for a programming language - especially
one that wants to be called a "scripting" language - to provide
facilities to help the programmer in the task of writing command
line tools. In Python, for a long time the support for this kind of
tasks has been devoted to the old fashioned getopt module. I have
never been particularly fond of getopt, since it required the programmer
to do a sensible amount of boring job even for the parsing of simple
argument lines. However, the situation has changed with the coming of
Python 2.3, and thanks to the great job of Greg Ward (the author of
optparse and Optik, its precursor) now the Python programmer
has at her disposal - in the standard library and not as an
add-on module - a fully fledged Object Oriented API for command
line argument parsing, which makes writing Unix-style command
line tools easy, efficient and fast.
The only minor disadvantage of optparse is that it is a kind of
sophisticated tool, and requires some time to be fully mastered.
The purpose of this paper is to help the reader to rapidly get the
10% of the features of optparse that she will use in the 90% of
the cases.
Taking as an example a real life application - a search and
replace tool - I will guide the reader through (some of) the wonders
of optparse, showing how easy is to use it and how convenient it
really is. Also, I will show some trick that will make your life with
optparse much easier. This paper is intended for both Unix and
Windows programmers - actually I will argue that Windows programmers
need optparse even more than Unix programmers - and does not
require any particular expertise to be fully appreciated.
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