[Baypiggies] Discussion for newbies/beginner night talks

[Shannon -jj Behrens]

On 2/9/07, Shannon -jj Behrens <jjinux at gmail.com> wrote:
> On 2/9/07, Chad Netzer <chad.netzer at gmail.com> wrote:
> > First, I want to thank Dennis and Drew for speaking last night, and
> > Jim Stockford for hosting the post talk discussion.
> >
> > I've created this thread to start discussion about the "newbie" night
> > that was talked about at the end of last night's meeting. If people
> > reply to this thread only (or mostly), those on the list who aren't
> > interested can easily ignore it.  If we are to host a beginners night,
> > it will be best to start organizing it soon, in order to line up
> > topics, speakers, make timely announcements, etc.
> >
> > One person at the meeting asked about Python "idioms", and in fact in
> > a previous email I brought up the idea of an "anti-idioms"
> > presentation. I'll get the ball rolling with a few idioms and tips
> > that I can think of, without explanation.  If people are interested in
> > the why, or wish to add some, please reply and discuss.  Perhaps it
> > could evolve into a good QA topic for beginners.
> >
> > Also, if people have other ideas or suggestions for a beginners night,
> > please feel free to discuss them here.
> >
> >
> >
> > Some Python beginner tips and idioms:
> >
> > 1) Do not use lists, dicts, or any mutable object as default
> > arguments; use None instead.
> >
> > 2) If you need to do a lot of string appends, use lists and join().
> >
> > 3) Understand and use iterators in loops.
> >
> > 4) Use dictionaries, sets, and other mappings for searches and
> > queries.
> >
> > 5) Understand and use the decorate/sort/undecorate (DSU) idiom.
> >
> > 6) Catch exceptions that you can handle, don't suppress ones you
> > can't.
> >
> > 7) Ask forgiveness, not permission. Ie. perform conversions and
> > other operations using "try". Avoid queries to determine if an
> > operation will succeed.
> >
> > 8) Use assert() to document your code.
> >
> > 9) Don't overuse tuples as "read only" lists.  Use them to make
> > dictionary keys, or pass around short lived groups of objects.
> >
> > 10) Use open() to open files, not file(). (trivial, perhaps)
>
> Sorry, I have more:
>
> #) Keep a Python shell open.  Import modules.  Use help(obj) within
> the shell.  Try things out.  Copy from the shell into your code.  The
> shell is a necessary part of the development environment.
>
> #) Use print instead of a debugger.  In rare cases, throw the
> following into your code:
>
> import pdb
> pdb.set_trace()
>
> Now, from within the debugger, instead of painstakingly tracing over
> your code, pretend you're in the Python shell and look around.
>
> #) In network servers, use a thread that listens on a unix socket as a
> backdoor.  It should act like a Python shell so you can look around
> your application as it's running.

#) Use the source.  Don't just read it!  Update it!  If you're having
a problem with a standard library module or a third-party module,
remember that you're not dealing with a compiled DLL.  You can log in
as root and throw some print statements into the thing!  Remember to
undo your changes before you leave.

-jj

-- 
http://jjinux.blogspot.com/