[Python-Dev] Switch statement (original) (raw)

M.-A. Lemburg mal at egenix.com
Tue Jun 13 09:08:10 CEST 2006

Michael Walter wrote:

Maybe "switch" became a keyword with the patch..

Ah, right. Good catch :-)

Regards, Michael > On 6/12/06, M.-A. Lemburg <mal at egenix.com> wrote: > Thomas Lee wrote: > > Hi all, > > > > As the subject of this e-mail says, the attached patch adds a "switch" > > statement to the Python language. > > > > However, I've been reading through PEP 275 and it seems that the PEP > > calls for a new opcode - SWITCH - to be added to support the new > > construct. > > > > I got a bit lost as to why the SWITCH opcode is necessary for the > > implementation of the PEP. The reasoning seems to be > > improving performance, but I'm not sure how a new opcode could improve > > performance. > > > > Anybody care to take the time to explain this to me, perhaps within the > > context of my patch? >>> Could you upload your patch to SourceForge ? Then I could add > it to the PEP. >>> Thomas wrote a patch which implemented the switch statement > using an opcode. The reason was probably that switch works > a lot like e.g. the for-loop which also opens a new block. >>> Could you explain how your patch works ? >>> BTW, I think this part doesn't belong into the patch: >>> > Index: Lib/distutils/extension.py > > =================================================================== > > --- Lib/distutils/extension.py (revision 46818) > > +++ Lib/distutils/extension.py (working copy) > > @@ -185,31 +185,31 @@ > > continue > > > > suffix = os.path.splitext(word)[1] > > - switch = word[0:2] ; value = word[2:] > > + switchword = word[0:2] ; value = word[2:] >>> -- > Marc-Andre Lemburg > eGenix.com >>> Professional Python Services directly from the Source (#1, Jun 12 2006) > >>> Python/Zope Consulting and Support ... http://www.egenix.com/ > >>> mxODBC.Zope.Database.Adapter ... http://zope.egenix.com/ > >>> mxODBC, mxDateTime, mxTextTools ... http://python.egenix.com/ > ______________________________________ > 2006-07-03: EuroPython 2006, CERN, Switzerland 20 days left >>> ::: Try mxODBC.Zope.DA for Windows,Linux,Solaris,FreeBSD for free ! :::: > _________________________ > Python-Dev mailing list > Python-Dev at python.org > http://mail.python.org/mailman/listinfo/python-dev > Unsubscribe: > http://mail.python.org/mailman/options/python-dev/michael.walter%40gmail.com >>>

Marc-Andre Lemburg eGenix.com

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