[Python-Dev] Fwd: PEP 310(with-syntax): close synonym of __exit__

Guido van Rossum guido at python.org
Tue Aug 26 14:06:54 EDT 2003

> Btw, if __exit__ is the only spelling then:
>    var = expr
>    if hasattr(var, "__enter__"):
>      var.__enter__()
>    try:
>      suite
>    finally:
>      var.__exit__()
> is maybe a better semantics. If someone uses some of his legacy
> file-like objects etc, but forgets to define at least __exit__, he
> gets a fail-fast behavior, otherwise he may have to track down data
> corruption or something like that...

Good idea!

--Guido van Rossum (home page: http://www.python.org/~guido/)

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