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http://hg.python.org/cpython/rev/87ecfd5cd5d1 changeset:   73541:87ecfd5cd5d1 branch:      2.7 parent:      73529:c3b063c82ae5 user:        Eli Bendersky date:        Mon Nov 14 01:02:20 2011 +0200 summary:   Normalize the keyword arguments documentation notation in re.rst. Closes issue #12875

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-.. function:: compile(pattern[, flags=0]) +.. function:: compile(pattern, flags=0)

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This issue and the patch are about parameters with *default* arguments, which makes a corresponding argument in a call *optional*. For Python functions, both required and optional arguments can be passed by position (unless disabled) or keyword. Which is to say, for Python functions, any argument can be a keyword argument. I suspect I am not the only person somewhat confused when people use 'keyword' to mean 'optional' or 'default'.

You're right, Terry. Sorry for the confusing commit message. By the way, I think you may be interested in the related http://bugs.python.org/issue13386 Eli