[Baypiggies] regex puzzle

[Tony Cappellini]

Take a look at Kodos.
It is a regular expression debugger, written in Python.
The project is in sourceforge

On Tue, Mar 11, 2008 at 10:47 AM, Aaron Maxwell <amax at redsymbol.net> wrote:
> Hi all,
>
>  I'm writing a tool with a command line interface, using the cmd module.  It
>  has a "log search" command, which accepts a regex pattern as an argument.
>
>  After tokenizing the input, I finally get what the user typed as the regex
>  pattern into a variable search_str:
>
>   regex = re.compile(search_str)
>   return [line for line in loglines if regex.search(line)]
>
>  The problem is that search_str is a variable of type str, not a raw string.
>  So the user will have to escape many characters: e.g., "\\bREPO" instead
>  of "\bREPO" as the pattern.
>
>  What I'd like to do is allow the user to type in the regular expression
>  directly, without them having to escape it.  Can someone suggest a good
>  solution?
>
>  I could obviously have my code escape search_str, coding it to manually
>  replace each special character (http://docs.python.org/ref/strings.html).
>  But that seems unpythonic (by which I mean "tedious and error prone" :)
>  There was a thread [0] that suggested using str.encode(), but I did not find
>  that to work - for example, with '\bRE'.encode('string_escape'), \b is
>  interpreted as '\x08', the backspace character.
>
>  Suggestions appreciated.
>
>  Thanks,
>  Aaron
>
>  [0] http://mail.python.org/pipermail/python-list/2004-December/296389.html
>
>  --
>  Aaron Maxwell
>  http://redsymbol.net
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