[Patches] [ python-Patches-1751800 ] Dict comprehensions

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Patches item #1751800, was opened at 2007-07-11 06:49
Message generated for change (Comment added) made by gvanrossum
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Category: Core (C code)
Group: Python 3000
Status: Open
>Resolution: Accepted
Priority: 5
Private: No
Submitted By: Thomas Wouters (twouters)
>Assigned to: Thomas Wouters (twouters)
Summary: Dict comprehensions

Initial Comment:
Dict comprehensions, implemented somewhat like:

d = {}
for key, value in gen():
  d[key] = value

A version that passes the generator directly to dict() might be faster (although it would have to generate tuples instead of two separate items on the stack, which may negate the benefit of doing the actual dict assignment in C) -- and of course the danger of passing the generator to a local or global 'dict' variable instead of the builtin 'dict'.

Includes tests, but not compiler-package or documentation changes (yet).


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>Comment By: Guido van Rossum (gvanrossum)
Date: 2007-07-11 08:12

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Check it in!  (This one I meant, not the other one which was my mistake.)

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Comment By: Georg Brandl (gbrandl)
Date: 2007-07-11 07:46

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I tested the patch shallowly, works fine. I think this is a good feature
to have, even if only for completeness.
The tests don't seem to be included.

compiler package changes won't be needed, as it has been removed from
Py3k,
but probably changes to parsermodule.c.

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