[Zope-dev] Re: [Zope-Checkins] SVN: Zope/trunk/lib/python/OFS/Traversable.py using startswith()
On 2/28/06, Andreas Jung [EMAIL PROTECTED] wrote:
-if name[0] == '_':
+if name.startswith('_'):
Just a question: Is this only a matter of stylistic changes, or is
there some, like, speedup involved?
--
Lennart Regebro, Nuxeo http://www.nuxeo.com/
CPS Content Management http://www.cps-project.org/
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[Zope-dev] Re: [Zope-Checkins] SVN: Zope/trunk/lib/python/OFS/Traversable.py using startswith()
Lennart Regebro wrote:
-if name[0] == '_':
+if name.startswith('_'):
Just a question: Is this only a matter of stylistic changes, or is
there some, like, speedup involved?
In general, using str.startswith and str.endswith is a failsafe because
''.startswith('_') simply returns False, ''[0] == '_' raises a KeyError.
So, if you really know that your string has at least the length you're
trying to test it against, using the index/slice notation is ok. In all
other cases I would prefer str.startswith and str.endswith.
Philipp
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Re: [Zope-dev] Re: [Zope-Checkins] SVN: Zope/trunk/lib/python/OFS/Traversable.py using startswith()
--On 28. Februar 2006 21:41:24 +0100 Philipp von Weitershausen
[EMAIL PROTECTED] wrote:
Lennart Regebro wrote:
-if name[0] == '_':
+if name.startswith('_'):
Just a question: Is this only a matter of stylistic changes, or is
there some, like, speedup involved?
In general, using str.startswith and str.endswith is a failsafe because
''.startswith('_') simply returns False, ''[0] == '_' raises a KeyError.
So, if you really know that your string has at least the length you're
trying to test it against, using the index/slice notation is ok. In all
other cases I would prefer str.startswith and str.endswith.
But Lennart is right that in this case name should in general never be an
empty string and in addition startswith() is in this case 100% slower
than using slicing.
-aj
pgpiYM5OXCXJu.pgp
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Re: [Zope-dev] Re: [Zope-Checkins] SVN: Zope/trunk/lib/python/OFS/Traversable.py using startswith()
But Lennart is right that in this case name should in general never be an empty string and in addition startswith() is in this case 100% slower than using slicing. No, I'm not, Florent is. I just asked. :-) -- Lennart Regebro, Nuxeo http://www.nuxeo.com/ CPS Content Management http://www.cps-project.org/ ___ Zope-Dev maillist - Zope-Dev@zope.org http://mail.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope )
