(original) (raw)

On Mon, Apr 23, 2018 at 8:20 AM, Mike Miller <python-dev@mgmiller.net> wrote:
\>
\> On 2018-04-22 14:33, Chris Angelico wrote:
\>>
\>> with open(fn) as f:
\>> with (open(fn) as f):
\>>
\>> These two do the same thing, but only because a file object's
\>> \_\_enter\_\_ returns self. So it's dangerous, because it WILL work... and
\>> people will get into the habit of parenthesizing to permit a 'with'
\>> statement to go across line breaks. And then they'll use a different
\>> context manager, like closing(), or a PsycoPG2 database connection (I
\>> think), where it returns something else. And it'll work, until they go
\>> over multiple lines, and then suddenly the semantics change.
\>
\>
\>
\> Why do you think folks will be rushing to parenthesize with statements when
\> it has always been a syntax error, there is years of code and docs that show
\> otherwise, no use cases, and will take years for 3.8 to trickle out?

Because it's been requested a number of times as a way to allow a
'with' statement to go across lines without backslashes.

If it becomes possible, it will be used.

ChrisA

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