----- Original Message -----
> From: Steven D'Aprano <st...@pearwood.info>
> To: python-list@python.org
> Cc:
> Sent: Friday, July 11, 2014 11:04 AM
> Subject: Re: How to decipher :re.split(r"(\(\([^)]+\)\))" in the example
>
> On Thu, 10 Jul 2014 23:33:27 -0400, Roy Smith wrote:
>
>> In article <mailman.11747.1405046292.18130.python-l...@python.org>,
>> Tim Chase <python.l...@tim.thechases.com> wrote:
>>
>>> On 2014-07-10 22:18, Roy Smith wrote:
>>> > > Outside this are \( and \): these are literal opening
> and closing
>>> > > bracket characters. So:
>>> > >
>>> > > \(\([^)]+\)\)
>>> >
>>> > although, even better would be to use to utterly awesome
>>> >> re.VERBOSE
>>> > flag, and write it as:
>>> >
>>> > \({2} [^)]+ \){2}
>>>
>>> Or heck, use a multi-line verbose expression and comment it for
>>> clarity:
>>>
>>> r = re.compile(r"""
>>> ( # begin a capture group
>>> \({2} # two literal "(" characters [^)]+
> # one or more
>>> non-close-paren characters \){2} # two literal
> ")"
>>> characters
>>> ) # close the capture group """,
> re.VERBOSE)
>>>
>>> -tkc
>>
>> Ugh. That reminds me of the classic commenting anti-pattern:
>
> The sort of dead-simple commenting shown below is not just harmless but
> can be *critically important* for beginners, who otherwise may not know
> what "l = []" means.
>
>> l = [] # create an empty list
>> for i in range(10): # iterate over the first 10 integers
>> l.append(i) # append each one to the list
>
Anything better than this hideous type of commenting: (?#...), e.g
>>> re.match("(19|20)[0-9]{2}(?#year)-[0-9]{2}(?#month)", "2010-12")
Same thing for the 'limsux' modifiers, although *maybe* they can be useful.
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