[Python-Dev] More on contextlib - adding back a contextmanager decorator

Nick Coghlan ncoghlan at gmail.com
Mon May 1 14:32:06 CEST 2006

Fredrik Lundh wrote:
> a distinct term for "whatever the __enter__ method returns" (i.e.
> the thing assigned to the target list) would still be nice.

I've called that the "context entry value" in a few places (I don't think any 
of them were in the actual documentation though).

A sample modification to the reference page:
Here's a more detailed description:

    1. The context expression is evaluated, to obtain a context guard.
    2. The guard object's __enter__ method is invoked to obtain the context
       entry value.
    3. If a target list was included in the with statement, the context entry
       value is assigned to it.
    4. The suite is executed.
    5. The guard object's __exit__ method is invoked. If an exception caused
       the suite to be exited, its type, value, and traceback are passed as
       arguments to __exit__. Otherwise, three None arguments are supplied.


Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia

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