in reply to Advanced regular expression help

The old wisdom applies: Parsing HTML with regexes is not good. If it's line based, try to parse it line based.

However if you insist on using regexes...

I don't quite get it - do you want the <ul id="ccc">(.*)</ul> part to be optional? If yes, make it optional: (?:<ul id="ccc">(.*)</ul>)?.

You have to take care that the .* doesn't consume too much text. What do you want the delimiter to be? Newlines? Then use \n or $ or ^ and use the /m modifier.

Also note that . won't match a newline unless the /s modifier is present (more on that in perlre):

Replies are listed 'Best First'.
Re^2: Advanced regular expression help
by Andrew Coolman (Hermit) on Sep 12, 2008 at 18:16 UTC
    As moritz suggested. Anyway if you want to use regex and just want to see $1 and $3 try to make the optional part capturing since you don't care about $2. Something like this: 
    my $regex = '<div id="aaaa">([.\w\s]*?)(<ul id="ccc">[.\s\w]*?</ul>)?(
+[.\s\w]*?)</div>';

    [download]
    This is the output if that's what you seek: 
    Text 1 found 
    text tex text

    more text
Text 2 found 
    text text text

    more text

    [download]

    Regards
    s++ą  ł˝ ął. Ş ş şą Żľ ľą˛ş ą ŻĽąş.}++y~-~?-{~/s**$_*ee
[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom