strtr? (was startsin ?
I think `strtr`_ in php is also very useful when escaping something.
_ strtr: http://jp.php.net/manual/en/function.strtr.php
For example:
.. code-block:: php
php> = strtr("foo\\\"bar\\'baz\\\\", array("\\\\"=>"\\",
'\\"'=>'"', "\\'"=>"'"));
"foo\"bar'baz\\"
.. code-block:: python
In [1]: "foo\\\"bar\\'baz\\\\".replace('\\"', '"').replace("\\'",
"'").replace('\\\\', '\\')
Out[1]: 'foo"bar\'baz\\'
In Python, lookup of 'replace' method occurs many times and temporary
strings is created many times too.
It makes Python slower than php.
And replacing order may cause very common mistake.
.. code-block:: python
In [4]: "foo\\\"bar\\'baz\\\\'".replace('\\\\',
'\\').replace('\\"', '"').replace("\\'", "'")
Out[4]: 'foo"bar\'baz\''
When I wrote HandlerSocket_ client in pure Python. I use dirty hack for speed.
http://bazaar.launchpad.net/~songofacandy/+junk/pyhandlersocket/view/head:/h...
I believe Pythonic means simple and efficient. My code is not Pythonic at all.
.. _HandlerSocket: https://github.com/ahiguti/HandlerSocket-Plugin-for-MySQL
On Sat, Oct 1, 2011 at 12:30 AM, Tarek Ziadé
Hey,
not sure how people do this, or if I missed something obvious in the stdlib, but I often have this pattern:
starts = ('a', 'b', 'c') somestring = 'acapulco'
for start in starts: if somestring.startswith(start): print "yeah"
So what about a startsin() method, that would iterate over a sequence:
if somestring.startsin('a', 'b', 'c'): print "yeah"
Implementing it in C should be faster as well
same deal with .endswith I guess
Cheers Tarek
-- Tarek Ziadé | http://ziade.org _______________________________________________ Python-ideas mailing list Python-ideas@python.org http://mail.python.org/mailman/listinfo/python-ideas
--
INADA Naoki
INADA Naoki dixit (2011-10-01, 01:18):
I think `strtr`_ in php is also very useful when escaping something.
_ strtr: http://jp.php.net/manual/en/function.strtr.php
For example:
.. code-block:: php
php> = strtr("foo\\\"bar\\'baz\\\\", array("\\\\"=>"\\", '\\"'=>'"', "\\'"=>"'")); "foo\"bar'baz\\"
.. code-block:: python
In [1]: "foo\\\"bar\\'baz\\\\".replace('\\"', '"').replace("\\'", "'").replace('\\\\', '\\') Out[1]: 'foo"bar\'baz\\'
In Python, lookup of 'replace' method occurs many times and temporary strings is created many times too. It makes Python slower than php.
For this particular case I'd use .decode('string_escape') for Py2.x str and .decode('unicode_escape') for Py2.x unicode strings. And in Py3.x I'd use... Er... In Py3.x the planned mechanism of str.transform()/untransform() (here: untransform('unicode_escape')) would be ideal -- but it has not been re-introduced yet: http://bugs.python.org/issue7475 -- and IMHO it should be as a clear way to do such transformations. Cheers. *j
On 2011-10-01, at 13:28 , Jan Kaliszewski wrote:
For this particular case I'd use .decode('string_escape') for Py2.x str and .decode('unicode_escape') for Py2.x unicode strings.
And in Py3.x I'd use... Er... In Py3.x the planned mechanism of str.transform()/untransform() (here: untransform('unicode_escape')) would be ideal -- but it has not been re-introduced yet: http://bugs.python.org/issue7475 -- and IMHO it should be as a clear way to do such transformations. If push comes to shove, re.sub with a replacement function.
participants (3)
-
INADA Naoki -
Jan Kaliszewski -
Masklinn