Why is the argparse module so inflexible?

Date	2013-06-27 07:54 -0500
From	Andrew Berg <robotsondrugs@gmail.com>
Subject	Why is the argparse module so inflexible?
Newsgroups	comp.lang.python
Message-ID	<mailman.3924.1372337705.3114.python-list@python.org> (permalink)

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I've begun writing a program with an interactive prompt, and it needs to parse input from the user. I thought the argparse module would be
great for this, but unfortunately it insists on calling sys.exit() at any sign of trouble instead of letting its ArgumentError exception
propagate so that I can handle it. Overriding ArgumentParser.error doesn't really help since methods like parse_known_args just send a
message to be relayed to the user as an argument after swallowing ArgumentError (which does have useful information in its attributes). If I
wanted to figure out what actually caused the exception to be raised, I'd have to parse the message, which is ugly at best. I understand
that most people do want argparse to just display a message and terminate if the arguments supplied aren't useful, but there's a lot of
potential in the module that is crippled outside the main use case. I have to wonder why a module that is meant to be imported would ever
call sys.exit(), even if that is what the caller would normally do if presented with an exception.
-- 
CPython 3.3.2 | Windows NT 6.2.9200 / FreeBSD 9.1

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Why is the argparse module so inflexible? Andrew Berg <robotsondrugs@gmail.com> - 2013-06-27 07:54 -0500
  Re: Why is the argparse module so inflexible? Roy Smith <roy@panix.com> - 2013-06-27 09:08 -0400
    Re: Why is the argparse module so inflexible? Andrew Berg <robotsondrugs@gmail.com> - 2013-06-27 08:49 -0500
    Re: Why is the argparse module so inflexible? Dave Angel <davea@davea.name> - 2013-06-27 12:02 -0400
      Re: Why is the argparse module so inflexible? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-06-27 22:49 +0000
        Re: Why is the argparse module so inflexible? Cameron Simpson <cs@zip.com.au> - 2013-06-28 09:34 +1000
        Re: Why is the argparse module so inflexible? Ethan Furman <ethan@stoneleaf.us> - 2013-06-28 18:36 -0700
          Re: Why is the argparse module so inflexible? rusi <rustompmody@gmail.com> - 2013-06-28 21:12 -0700
            Re: Why is the argparse module so inflexible? Terry Reedy <tjreedy@udel.edu> - 2013-06-29 00:37 -0400
              Re: Why is the argparse module so inflexible? Roy Smith <roy@panix.com> - 2013-06-29 10:12 -0400
                Re: Why is the argparse module so inflexible? Andrew Berg <robotsondrugs@gmail.com> - 2013-06-29 09:17 -0500
          Re: Why is the argparse module so inflexible? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-06-29 05:28 +0000
            Re: Why is the argparse module so inflexible? Marcin Szamotulski <mszamot@gmail.com> - 2013-06-29 13:38 +0100
            Re: Why is the argparse module so inflexible? MRAB <python@mrabarnett.plus.com> - 2013-06-29 16:58 +0100
            Re: Why is the argparse module so inflexible? Ethan Furman <ethan@stoneleaf.us> - 2013-06-29 12:17 -0700
        Re: Why is the argparse module so inflexible? Modulok <modulok@gmail.com> - 2013-06-28 19:39 -0600
        Re: Why is the argparse module so inflexible? Isaac To <isaac.to@gmail.com> - 2013-06-29 12:37 +0800
    Re: Why is the argparse module so inflexible? Robert Kern <robert.kern@gmail.com> - 2013-06-27 20:47 +0100

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