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Re: Curious to see alternate approach on a search/replace via regex

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On Thu, Feb 7, 2013 at 4:59 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> Oh, one last thing... pulling out "re.compile" outside of the function does
> absolutely nothing. You don't even compile anything. It basically looks up
> that a compile function exists in the re module, and that's all.

Using Python 2.7:

>>> t1 = Timer("""
... nx = re.compile(r'https?://(.+)$')
... v = nx.search(u).group(1)
... ux = re.compile(r'([-:./?&=]+)')
... ux.sub('_', v)""", """
... import re
... u = 'http://alongnameofasite1234567.com/q?sports=run&a=1&b=1'""")
>>> t2 = Timer("""
... v = nx.search(u).group(1)
... ux.sub('_', v)""", """
... import re
... nx = re.compile(r'https?://(.+)$')
... ux = re.compile(r'([-:./?&=]+)')
... u = 'http://alongnameofasite1234567.com/q?sports=run&a=1&b=1'""")
>>> min(t1.repeat())
11.625409933385388
>>> min(t2.repeat())
8.825254885746652

Whatever caching is being done by re.compile, that's still a 24%
savings by moving the compile calls into the setup.

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Re: Curious to see alternate approach on a search/replace via regex Demian Brecht <demianbrecht@gmail.com> - 2013-02-06 13:55 -0800
  Re: Curious to see alternate approach on a search/replace via regex Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-07 03:04 +0000
    Re: Curious to see alternate approach on a search/replace via regex rh <richard_hubbe11@lavabit.com> - 2013-02-06 19:31 -0800
      Re: Curious to see alternate approach on a search/replace via regex Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-08 09:45 +1100
        Re: Curious to see alternate approach on a search/replace via regex rh <richard_hubbe11@lavabit.com> - 2013-02-07 15:13 -0800
          Re: Curious to see alternate approach on a search/replace via regex Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-08 10:59 +1100
            Re: Curious to see alternate approach on a search/replace via regex Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-07 17:55 -0700
              Re: Curious to see alternate approach on a search/replace via regex Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-08 14:02 +1100
                Re: Curious to see alternate approach on a search/replace via regex rh <richard_hubbe11@lavabit.com> - 2013-02-07 21:35 -0800
            Re: Curious to see alternate approach on a search/replace via regex Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-07 18:08 -0700
            Re: Curious to see alternate approach on a search/replace via regex rh <richard_hubbe11@lavabit.com> - 2013-02-07 21:57 -0800
            Re: Curious to see alternate approach on a search/replace via regex Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-08 01:21 -0700
              Re: Curious to see alternate approach on a search/replace via regex Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-08 22:43 +1100
                Re: Curious to see alternate approach on a search/replace via regex Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-08 09:26 -0700
            Re: Curious to see alternate approach on a search/replace via regex Serhiy Storchaka <storchaka@gmail.com> - 2013-02-15 22:58 +0200
            Re: Curious to see alternate approach on a search/replace via regex rh <richard_hubbe11@lavabit.com> - 2013-02-26 11:20 -0800
        Re: Curious to see alternate approach on a search/replace via regex Dave Angel <davea@davea.name> - 2013-02-08 01:27 -0500
    Re: Curious to see alternate approach on a search/replace via regex jmfauth <wxjmfauth@gmail.com> - 2013-02-07 03:08 -0800
      Re: Curious to see alternate approach on a search/replace via regex Chris Angelico <rosuav@gmail.com> - 2013-02-07 23:44 +1100

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