[Python-ideas] with-statement syntactic quirk
grosser.meister.morti at gmx.net
Thu Nov 1 03:46:36 CET 2012
On 10/31/2012 10:03 PM, Arnaud Delobelle wrote:
> On 31 October 2012 10:38, Barry Warsaw <barry at python.org> wrote:
>> with-statements have a syntactic quirk, which I think would be useful to fix.
>> This is true in Python 2.7 through 3.3, but it's likely not fixable until 3.4,
>> unless of course it's a bug <wink>.
>>>>> with open('/etc/passwd') as p1, open('/etc/passwd') as p2: pass
>> Not legal:
>>>>> with (open('/etc/passwd') as p1, open('/etc/passwd') as p2): pass
>> Why is this useful? If you need to wrap this onto multiple lines, say to fit
>> it within line length limits. IWBNI you could write it like this:
>> with (open('/etc/passwd') as p1,
>> open('/etc/passwd') as p2):
>> This seems analogous to using parens to wrap long if-statements, but maybe
>> there's some subtle corner of the grammar that makes this problematic (like
>> 'with' treating the whole thing as a single context manager).
>> Of course, you can wrap with backslashes, but ick!
> No need for backslashes, just put the brackets in the right place:
> with (
> open('/etc/passwd')) as p1, (
> open('/etc/passwd')) as p2:
Because that's not confusing. Why not write:
) as p1, open(
'/etc/passwd') as p2:
More information about the Python-ideas