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| OptParse is a module introduced in Python2.3 that makes it easy to write command line tools. | OptParse is a module introduced in Python2.3 that makes it easy to write command line tools. See "[[Option parsing tools]]" for others. Note that OptParse is considered deprecated (in Python 2.7 and 3.2) in favor of the [[http://docs.python.org/3/library/argparse.html|argparse]] module. |
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| * [http://docs.python.org/lib/module-optparse.html Official Python optparse Documentation] | * [[http://docs.python.org/lib/module-optparse.html|Official Python optparse Documentation]] |
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| == Discussion == | == Complaints == |
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| * Impossible to verify the amount of options passed. | optparse does not support 'required' arguments. The documentation justifies this by saying 'options are optional'. But look at python and its use of keyword arguments. And look at optparse iself! It has the required option 'action'! optparse is a utility! Not a way to enforce a philosphy. |
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| I have had to create a function to verify in certain circumstances if we have at least one option set: (takes an OptParse Values instances returned by parser.parse_args() as argument) {{{ #!python def is_empty(options): """ Returns True or False if an option is set or not. """ values = options.__dict__.values() return (values == [None] * len(values)) }}} Is my need for this is due to a bad design in my option parsing? |
See [[http://mail.python.org/pipermail/getopt-sig/2002-February/000016.html|this thread]] in the retired [[http://mail.python.org/mailman/listinfo/getopt-sig|getopt-sig]] mailing list. I also seem to remember a more protracted discussion about "required" arguments/options. ''-- David Boddie'' |
OptParse is a module introduced in Python2.3 that makes it easy to write command line tools. See "Option parsing tools" for others. Note that OptParse is considered deprecated (in Python 2.7 and 3.2) in favor of the argparse module.
You give a description of the options that the program can receive, and OptParse will do reasonable stuff for you.
For example:
1 import optparse
2
3 if __name__=="__main__":
4 parser = optparse.OptionParser("usage: %prog [options] arg1 arg2")
5 parser.add_option("-H", "--host", dest="hostname",
6 default="127.0.0.1", type="string",
7 help="specify hostname to run on")
8 parser.add_option("-p", "--port", dest="portnum", default=80,
9 type="int", help="port number to run on")
10
11 (options, args) = parser.parse_args()
12 if len(args) != 2:
13 parser.error("incorrect number of arguments")
14 hostname = options.hostname
15 portnum = options.portnum
args contains your fixed arguments, options contains your values.
For example, options.portnum would contain the integer 80, in the example above.
References
Complaints
- optparse does not support 'required' arguments. The documentation justifies this by saying 'options are optional'. But look at python and its use of keyword arguments. And look at optparse iself! It has the required option 'action'! optparse is a utility! Not a way to enforce a philosphy.
See this thread in the retired getopt-sig mailing list. I also seem to remember a more protracted discussion about "required" arguments/options. -- David Boddie