Mailman 3 with-statement syntactic quirk - Python-ideas

31 Oct 2012

      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>.

Legal:
...
...
...
with open('/etc/passwd') as p1, open('/etc/passwd') as p2: pass
Not legal:
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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):
          pass

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!

Cheers,
-Barry

with-statement syntactic quirk

Barry Warsaw

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