On Wed, Nov 13, 2019 at 11:26 AM MRAB <python@mrabarnett.plus.com> wrote:
"with" expression ["as" name] ":"
but the expression itself can start with a parenthesis, so if it saw a parenthesis after the "with" it would be ambiguous
I have used 'with' for so long that I was under the impression that the as-target was just a name as in MRAB's simplified syntax above, so imagine my surprise when I tried putting parentheses around the target and didn't get a syntax error straight away. I of course had to explore a bit, and came up with this. The ugly formatting of the with is simply to show that the parens behave as expected. class opener: def __init__(self, *files): self.files = [open(file) for file in files] def __enter__(self): return [file.__enter__() for file in self.files] def __exit__(self, *exc_info): for file in self.files: file.__exit__(*exc_info) return True with opener( 'x', 'y', 'z' ) as ( f1, f2, f3 ): print(f1) print(f1.closed) print(f2) print(f3) print(f1.closed)