Hi,
I'm currently implementing a parser to handle Python 3.0, and one of the points I found conflicting with the grammar specification is the PEP 3104.
It says that a shortcut would be added to Python 3.0 so that "nonlocal x = 0" can be written. However, the latest grammar specification (http://docs.python.org/dev/3.0/reference/grammar.html?highlight=full%20gramm...) doesn't seem to take that into account... So, can someone enlighten me on what should be the correct treatment for that on a grammar that wants to support Python 3.0?
Thanks,
Fabio
Hello,
Fabio Zadrozny wrote:
Hi,
I'm currently implementing a parser to handle Python 3.0, and one of the points I found conflicting with the grammar specification is the PEP 3104.
It says that a shortcut would be added to Python 3.0 so that "nonlocal x = 0" can be written. However, the latest grammar specification (http://docs.python.org/dev/3.0/reference/grammar.html?highlight=full%20gramm...) doesn't seem to take that into account... So, can someone enlighten me on what should be the correct treatment for that on a grammar that wants to support Python 3.0?
An issue was already filed about this: http://bugs.python.org/issue4199 It should be ready for inclusion in 3.0.1.
I'm currently implementing a parser to handle Python 3.0, and one of the points I found conflicting with the grammar specification is the PEP 3104.
It says that a shortcut would be added to Python 3.0 so that "nonlocal x = 0" can be written. However, the latest grammar specification (http://docs.python.org/dev/3.0/reference/grammar.html?highlight=full%20gramm...) doesn't seem to take that into account... So, can someone enlighten me on what should be the correct treatment for that on a grammar that wants to support Python 3.0?
An issue was already filed about this: http://bugs.python.org/issue4199 It should be ready for inclusion in 3.0.1.
Thanks for pointing that out.
Fabio
On Sun, Dec 7, 2008 at 2:45 PM, Amaury Forgeot d'Arc amauryfa@gmail.com wrote:
Hello,
Fabio Zadrozny wrote:
Hi,
I'm currently implementing a parser to handle Python 3.0, and one of the points I found conflicting with the grammar specification is the PEP 3104.
It says that a shortcut would be added to Python 3.0 so that "nonlocal x = 0" can be written. However, the latest grammar specification (http://docs.python.org/dev/3.0/reference/grammar.html?highlight=full%20gramm...) doesn't seem to take that into account... So, can someone enlighten me on what should be the correct treatment for that on a grammar that wants to support Python 3.0?
An issue was already filed about this: http://bugs.python.org/issue4199 It should be ready for inclusion in 3.0.1.
No it should not. It should be put in 3.1.
I strongly object against the addition of features of *any* kind to 3.0.1, no matter whether they were promised or announced in a PEP or in the docs or on the 8 o'clock news. This would make 3.0.0 forever a "loser" release.
(I find the removal of 'cmp' hard to swallow too, but in a sense the addition of features is worse, as it makes downgrading a risk. Upgrades, no matter how minimal, always represent risks -- however downgrading shouldn't represent risks, unless you happen to depend on a bugfix that wasn't present in the downgrade -- but we're not talking about a bugfix here no matter how you bend the English language.)
Did the original PEP discussion cover debates about the shortcut working for all assignment operators (like += and x[i] =) and the difference between it being one-shot (doesnt affect x for the rest of the function) or simply the unrolling into nonlocal x; x= y as it is?
On Mon, Dec 8, 2008 at 5:07 PM, Guido van Rossum guido@python.org wrote:
On Sun, Dec 7, 2008 at 2:45 PM, Amaury Forgeot d'Arc amauryfa@gmail.com wrote:
Hello,
Fabio Zadrozny wrote:
Hi,
I'm currently implementing a parser to handle Python 3.0, and one of the points I found conflicting with the grammar specification is the PEP 3104.
It says that a shortcut would be added to Python 3.0 so that "nonlocal x = 0" can be written. However, the latest grammar specification (http://docs.python.org/dev/3.0/reference/grammar.html?highlight=full%20gramm...) doesn't seem to take that into account... So, can someone enlighten me on what should be the correct treatment for that on a grammar that wants to support Python 3.0?
An issue was already filed about this: http://bugs.python.org/issue4199 It should be ready for inclusion in 3.0.1.
No it should not. It should be put in 3.1.
I strongly object against the addition of features of *any* kind to 3.0.1, no matter whether they were promised or announced in a PEP or in the docs or on the 8 o'clock news. This would make 3.0.0 forever a "loser" release.
(I find the removal of 'cmp' hard to swallow too, but in a sense the addition of features is worse, as it makes downgrading a risk. Upgrades, no matter how minimal, always represent risks -- however downgrading shouldn't represent risks, unless you happen to depend on a bugfix that wasn't present in the downgrade -- but we're not talking about a bugfix here no matter how you bend the English language.)
-- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/ironfroggy%40gmail.com
Fabio Zadrozny wrote:
Hi,
I'm currently implementing a parser to handle Python 3.0, and one of the points I found conflicting with the grammar specification is the PEP 3104.
It says that a shortcut would be added to Python 3.0 so that "nonlocal x = 0" can be written.
As near as I can tell from testing, that did not happen. The PEP needs revision to delete that or push it to a later version.
However, the latest grammar specification (http://docs.python.org/dev/3.0/reference/grammar.html?highlight=full%20gramm...) doesn't seem to take that into account... So, can someone enlighten me on what should be the correct treatment for that on a grammar that wants to support Python 3.0?
participants (5)
-
Amaury Forgeot d'Arc -
Calvin Spealman -
Fabio Zadrozny -
Guido van Rossum -
Terry Reedy