[Python-Dev] anyone tried to use optparse with something else than sys.argv?

[Greg Ward]

[cc'ing optik-users@lists.sourceforge.net, since this concerns
 Optik's reincarnation as optparse in the Python standard library]

On 10 December 2002, Erik Heneryd said (on python-dev):
> snuck a peek at the newly included optparse module yesterday and it seems
> option parsing will be a breeze in the future.  good work!

Thanks!

> well, to me, it's pretty obvious that the design effort on optparse has
> pretty much been focused strictly on initial sys.argv parsing and while
> it's extendable, other use cases (embedded consoles etc) seem to have been
> given little or no real thought.

Guilty as charged.  My intention was always to support that kind of
stuff, but I've never had occasion to test it myself.  Sounds like I
carefully hid lots of little bugs in there -- congrats for finding them.
;-)

> the things i mention is probably easy to fix:
> 
> * make parse_args() take the whole "sys.argv" list and use the first
> element as the command name.  breaks backward compatibility, i know.

Since optparse is new to the stdlib as of Python 2.3, backwards
compatibility is not a huge concern; anyone switching from Optik to
optparse will have to make changes anyways.  So this is an option.

> why was sys.argv[1:] used in the first place?  the getopt legacy?

Gee, good question.  I can assure you it had nothing to do with getopt.
I think it was because, despite Unix/libc conventions, I don't see the
program name as part of the argument list.  That's a perfectly valid
interpretation, but I failed to allow a clean/obvious way to override
argv[0].

Idea: add a keyword arg 'prog' to OptionParser.__init__() that sets
self.prog, and then make get_prog_name() a method that returns self.prog
or sys.argv[0].  That feels right.  The other possibility is to add a
'prog' argument to parse_args(), but I'm not sure offhand what would
happen to it (and how it would find its way to down to usage/version
strings.)

Anyways, thanks for the bug reports.  I'll use your message as a to-do
list for Optik 1.4.1.

        Greg
-- 
Greg Ward <gward@python.net>                         http://www.gerg.ca/
Think honk if you're a telepath.