Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.python > #79835

Re: Regex substitution trouble

References <8c1c1b7f-d121-4f3d-adf9-8262ddd8f102@googlegroups.com>
Date 2014-10-28 22:24 +1100
Subject Re: Regex substitution trouble
From Chris Angelico <rosuav@gmail.com>
Newsgroups comp.lang.python
Message-ID <mailman.15258.1414495491.18130.python-list@python.org> (permalink)

Show all headers | View raw


On Tue, Oct 28, 2014 at 10:02 PM,  <massi_srb@msn.com> wrote:
> I'm not really sure if this is the right place to ask about regular expressions, but since I'm usin python I thought I could give a try :-)

Yeah, that sort of thing is perfectly welcome here. Same with
questions about networking in Python, or file I/O in Python, or
anything like that. Not a problem!

> Here is the problem, I'm trying to write a regex in order to substitute all the occurences in the form $"somechars" with another string. This is what I wrote:
>
> newstring = re.sub(ur"""(?u)(\$\"[\s\w]+\")""", subst, oldstring)
>
> This works pretty well, but it has a problem, I would need it also to handle the case in which the internal string contains the double quotes, but only if preceeded by a backslash, that is something like $"somechars_with\\"doublequotes".
> Can anyone help me to correct it?

But this is a problem. You can use look-ahead assertions and such to
allow the string \" inside your search string, but presumably the
backslash ought itself to be escapable, in order to make it possible
to have a loose backslash legal at the end of the string. I suggest
that, instead of a regex, you look for a different way of parsing.
What's the surrounding text like?

ChrisA

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread


Thread

Regex substitution trouble massi_srb@msn.com - 2014-10-28 04:02 -0700
  Re: Regex substitution trouble Chris Angelico <rosuav@gmail.com> - 2014-10-28 22:24 +1100
    Re: Regex substitution trouble massi_srb@msn.com - 2014-10-28 05:28 -0700
      Re: Regex substitution trouble Chris Angelico <rosuav@gmail.com> - 2014-10-28 23:59 +1100
      Re: Regex substitution trouble MRAB <python@mrabarnett.plus.com> - 2014-10-28 17:52 +0000
  Re: Regex substitution trouble TP <wingusr@gmail.com> - 2014-10-28 06:25 -0700
  Re: Regex substitution trouble Tim <jtim.arnold@gmail.com> - 2014-10-28 09:38 -0700
  Re: Regex substitution trouble Cameron Simpson <cs@zip.com.au> - 2014-10-29 13:14 +1100
  Re: Regex substitution trouble Eugene <hexumg@gmail.com> - 2014-11-05 13:44 +0300

csiph-web