[Python-Dev] PEP 343 rewrite complete

[Nick Coghlan]

Guido van Rossum wrote:
> I hope that I've got the rewrite of PEP 343 to include generator
> extensions right now. I've chosen the 'with' keyword. Please review
> here; I think this is ready for review by the unwashed masses. :-)
> 
>   http://www.python.org/peps/pep-0343.html
> 

Looks pretty good to me (looking at version 1.19).

One comment is that, in the 'optional extensions' section, where you 
say 'such mistakes are easily diagnosed', you could point to your 
generator wrapper as an example where attempting to reuse the block 
handler raises a RuntimeError on the second attempt.

Also, I'm wondering if it would be useful to have a 'closing' template 
that looked like:

   @with_template
   def closing(obj):
       try:
           yield obj
       finally:
           obj.close()

That can be used to deterministically close anything with a close 
method, be it file, generator, or something else:

   with closing(open("argument.txt")) as contradiction:
      for line in contradiction:
          print line

   with closing(some_gen()) as data:
      for datum in data:
          process(datum)


Cheers,
Nick.

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