[Python-Dev] Proposed changes to PEP 343

[Nick Coghlan]

Greg Ewing wrote:
> Jason Orendorff wrote:
> 
> 
>>    A contextmanager is a function that returns a new context manager.
>>
>>Okay, that last bit is weird.
> 
> 
> If the name of the decorator is to be 'contextmanager', it
> really needs to say something like
> 
>    The contextmanager decorator turns a generator into a
>    function that returns a context manager.
> 
> So maybe the decorator should be called 'contextmanagergenerator'.
> Or perhaps not, since that's getting rather too much of an
> eyeful to parse...

Strictly speaking this fits in with the existing confusion of "generator 
factory" and "generator":

Py> def g():
...     yield None
...
Py> type(g)
<type 'function'>
Py> type(g())
<type 'generator'>

Most people would call "g" a generator, even though its really just a factory 
function that returns generator objects.

So technically, the "contextmanager" decorator turns a generator factory 
function into a context manager factory function.

But its easier to simply say that the decorator turns a generator into a 
context manager, even if that's technically incorrect.

Cheers,
Nick.

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