Parsing multiple lines from text file using regex

[Rhodri James]

On Sun, 27 Oct 2013 21:09:46 -0000, Marc <marc at marcd.org> wrote:

> Hi,
> I am having an issue with something that would seem to have an easy
> solution, but which escapes me.  I have configuration files that I would
> like to parse.  The data I am having issue with is a multi-line attribute
> that has the following structure:
>
> banner <option> <banner text delimiter>
> Banner text
> Banner text
> Banner text
> ...
> <banner text delimiter>
>
> The regex 'banner\s+(\w+)\s+(.+)' captures the command nicely and
> banner.group(2) captures the delimiter nicely.
>
> My issue is that I need to capture the lines between the delimiters (both
> delimiters are the same).

I really, really wouldn't do this with a single regexp.  You'll get a much  
easier to understand program if you implement a small state machine  
instead.  In rough pseudocode:

collecting_banner = False
for line in configuration_file:
     if not collecting_banner:
         if found banner start:
             get delimiter
             collecting_banner = True
             banner_lines = []
         elif found other stuff:
             do other stuff
     elif found delimiter:
         collecting_banner = False
     else:
         banner_lines.append(line)

-- 
Rhodri James *-* Wildebeest Herder to the Masses