and a simple reg exp poser

stew has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: and a simple reg exp poser by diotalevi (Canon) on Jan 30, 2003 at 14:56 UTC
Solved without a regex so it's even clearer `if ( -1 != index $log, '198.167.1.10' ) { push @ip, $log; # or... print $log # or whatever makes sense for you } # OR just written differently push @ip, $log if -1 != index $log, '198.167.1.10'; print $log if -1 != index $log, '198.167.1.10'; # Or... as a regexp but I prefer it the other way push @ip, $log if $log =~ /198\.167\.1\.10/; print $log if $log =~ /198\.167\.1\.10/;` [download] Update Ok, maybe a regex is better because then then it can be written like `/198\.167\.1\.10(?!\d)/` which would fix the problem Abigail-II pointed out. Seeking Green geeks in Minnesota	[reply] [d/l] [select]
Re: and a simple reg exp poser by Abigail-II (Bishop) on Jan 30, 2003 at 23:03 UTC
That would capture lines containing `198.167.1.103`. Abigail	[reply] [d/l]
Re: and a simple reg exp poser by Cabrion (Friar) on Jan 30, 2003 at 15:11 UTC
The suggestions so far don't really do what you said you wanted done. 1) All lines starting with a particular IP. 2) Assuming "bung"="add" that it's an additive thing, not an overwrite thing. `my @ip while (<LOG>) { #assuming you are looping through a log file my $log = $_; #making this blatent push(@ip, $log) if $log =~ /^192\.168\.1\.10/;` [download] From your code, the 'g' modifier means match as many times as possibe. From mine, '^' is an anchor to the begining of the string. From your code, '@ip = $log' overwrites the values of `$ip[0]` each time. From my code, 'push(@ip, $log)' adds the entire line to the end of the array. Update: diotalevi's concept of using index instead of a regexp was an excellent suggestion that avoids regex engine overhead, so . . . `push(@ip, $log) if 0 == index($log,'192.168.1.10');` [download] Which gives you those that start with the ip in question.	[reply] [d/l] [select]
Re: and a simple reg exp poser by Jaap (Curate) on Jan 30, 2003 at 14:51 UTC
try this: `@ip = $log =~/(192\.168\.1\.10.*?)\n/g;` [download] (not tested)	[reply] [d/l]
Re^2: and a simple reg exp poser by diotalevi (Canon) on Jan 30, 2003 at 15:02 UTC
stew asserted that the entire line should be captured. Your expression ignores everything on the line prior to the match. You want to just store the value of $log if it's a match, not do some fancy footwork with capturing. Its just buggy this way. Seeking Green geeks in Minnesota	[reply]
Re: Re: and a simple reg exp poser by stew (Scribe) on Jan 30, 2003 at 14:58 UTC
(tested) Thank you!	[reply]
Re: and a simple reg exp poser by robartes (Priest) on Jan 30, 2003 at 15:00 UTC
How's this: `#!/usr/local/bin/perl -w use strict; my $log="192.168.1.254 was around"; my $ip="192.168.1.254"; my @ip; push @ip,($log =~ /(^\Q$ip\E.$)/); print @ip; __END__ 192.168.1.254 was around` [download] Update*: Added ^ anchor, poster wanted IP at start of string. CU Robartes-	[reply] [d/l]