Re: Regex keep matching the last possible match (but should get all)

Actually, the very first .+ in your regex will gobble up as many characters as possible to still match the whole pattern that follows.

In other words, after meeting the first <TD ALIGN=LEFT, .+ will match everything up to the last extinfo.cgi in your long string.

To see what I mean, put the first .+ between brackets and print $1.

.+ (and its even more treacherous brother .*) will quickly escape your control if you are not careful. A useful technique to control what gets matched is to indicate the character(s) you don't want: [^>]+, means match anything, except the '>' character, or in other words, until the end of the current HTML tag. It prevents the regex quantifiers to run away.

CountZero

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Re^2: Regex keep matching the last possible match (but should get all) by Anonymous Monk on May 18, 2015 at 12:48 UTC
Dear Perl-Monk, now I understand whats up with the `[^<]+` that has been suggested already. And you are totally right - If I put in brackets whats before the wanted first group, I'll get the whole html-file up to the very last extinfo... Sadly, when I try to use `[^>]+` it still does grab all the content up to the last position. snip `/'extinfo\.cgi[^>]+(.+)<\/A.+'status.+>(.+)<\/TD.+nowrap>(.+)<\/TD.+no +wrap>(.+s)<\/TD>.+'>(\d\/\d)<\/TD>.+'>(.+)<\/TD>/g)` [download] this will place the whole html file in $1 except for the next groups. How do I have to write this area behind the 'extinfo\.cgi' to make it stop at the > and get the group correctly? I tried to use `/'extinfo\.cgi[^>]+>(.+)<\/A.+'status.+>(.+)<\/TD.+nowrap>(.+)<\/TD.+n +owrap>(.+s)<\/TD>.+'>(\d\/\d)<\/TD>.+'>(.+)<\/TD>/g)` [download] which yield the same result: all of the .html-file inside $1 except for the last group-matches. I tried to use something like `/bla\w{,100}>(.+)<`, but this won't match any more. sigh a whole working day right now just for making a single RegEx... And I see it comming that I have to insert this "stop at the next whatever" everywhere, because the next .+ between the first () will keep going to the end too, isn't it? Greetings, a tired Visitor	[reply] [d/l] [select]
Re^3: Regex keep matching the last possible match (but should get all) by Corion (Patriarch) on May 18, 2015 at 12:52 UTC
Please re-read and understand when to use `[^>]` and when to use `[^<]`. They are to be used in different situations, as I already told you.	[reply] [d/l] [select]
Re^3: Regex keep matching the last possible match (but should get all) by Anonymous Monk on May 18, 2015 at 12:53 UTC
its me again (I truly need an account here), stop pondering about my problem for a while, because I think I figured out how to write the RegEx-Chain of Doom I need to get what I want.	[reply]