Newbie Getopts Question

[Justin Sheehy]

"Andrew N. McGuire" <amcguire at coastalnet.com> writes:

> this seems like a somewhat ineffecient way of handling options.

There are certainly some things you can do to make your code cleaner
here.  However, you are not alone in your judgement of the standard
getopt module.  It works quite well, but is not as feature-rich as
many people would like.  

Those people don't seem to agree on exactly how it should be better,
though.  Thus, several people have written their own getopt modules.

I've seen one or two private in-house implementations, and a number of 
people have posted their own getopt replacements here.  I have also
done this, though to suit a specific need: I wrote a getopt-like
module that was designed to mimic the functionality of the argument
parsing in the suites of user commands for manipulating the Andrew
File System.  If anyone wants such a beast, feel free to ask me for it.

With that diversion out of the way, I'll see if I can offer any useful
suggestions about the code here...

> arglist = sys.argv[1:]

This isn't necessary.  It could even be confusing, since you use that
name for something else afterward.  You can omit this and just
replace the following line:

>     optlist, arglist = getopt.getopt(arglist, 'f:n:i:o:c:')

With:

      optlist, arglist = getopt.getopt(sys.argv[1:], 'f:n:i:o:c:')

> list = []
> 
> for opt in optlist:
>     list.append(opt[0])

Just because of all of the bad press map and lambda have had lately ;->,
I'll mention that this whole snippet can be done as follows, among
other ways:

list = map(lambda x: x[0], optlist)

> for opt in optlist:

I recommend something more like:

  for opt, value in optlist:

Then you can replace all following uses of `opt[0]' and `opt[1]' with
`opt' and `value', respectively.  Tuple unpacking in this sort of
context is a wonderful feature that I use frequently.

I'm sure that as you continue to familiarize yourself with Python, you 
will find many more ways to improve your code.

-Justin