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pythoncommand-line-argumentsargparse

argparse store false if unspecified

parser.add_argument('-auto', action='store_true')

How can I store false if -auto is unspecified? I can faintly remember that this way, it stores None if unspecified

Solution

  • The store_true option automatically creates a default value of False.

    Likewise, store_false will default to True when the command-line argument is not present.

    The source for this behavior is succinct and clear: http://hg.python.org/cpython/file/2.7/Lib/argparse.py#l861

    The argparse docs aren't clear on the subject, so I'll update them now: http://hg.python.org/cpython/rev/49677cc6d83a