RegEx, $1, problem

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

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Re: RegEx, $1, problem by ikegami (Patriarch) on Oct 28, 2004 at 14:52 UTC
Change `\w\|\.+` to `(?:\w\|\.)+`. You're currently matching single letter filenames and filenames consiting of multiple '.' followed by 'zip' because the `+` binds very tightly. You do need to parens around what you you want in $1: `/<b>((?:\w\|\.)+\.zip)<\/b>/;`	[reply] [d/l] [select]
Re^2: RegEx, $1, problem by Anonymous Monk on Oct 28, 2004 at 14:55 UTC
This fixed it. Thanks.	[reply]
•Re: RegEx, $1, problem by merlyn (Sage) on Oct 28, 2004 at 14:48 UTC
This should work better: `next unless $string =~ /<b>(\w\|\.+\.zip)<\/b>/; &do_something_with($1);` [download] You have to have a successful match to have a $1. -- Randal L. Schwartz, Perl hacker Be sure to read my standard disclaimer if this is a reply. update: Ahh, I thought your problem was in not having a $1 after a failed match, but you've later determined it was your regex. My advice applies, just to a different problem. {grin}	[reply] [d/l]
Re^2: RegEx, $1, problem by ikegami (Patriarch) on Oct 28, 2004 at 14:56 UTC
Isn't that the same as as the OP? You negated the `if` to `unless` AND the `=~` to `!~` for a net change of nothing.	[reply] [d/l] [select]
Re^2: RegEx, $1, problem by Anonymous Monk on Oct 28, 2004 at 14:54 UTC
Same problem. If i remove the paren's it matches fine. If i add them back in nothing gets matched. I removed the "&do_something_with($1);" and replaced it with: `print "got here.\n";` [download] for the sake of testing. those parens seem to be screwing it up. Perl version is 5.8.1-RC3 (comes with macosx)	[reply] [d/l]
Re: RegEx, $1, problem by borisz (Canon) on Oct 28, 2004 at 15:04 UTC
You want: `next unless $string =~ /<b>([\w\.]+\.zip)<\/b>/;` [download] Boris	[reply] [d/l]
Re: RegEx, $1, problem by Happy-the-monk (Canon) on Oct 28, 2004 at 14:52 UTC
next if ... Whenever your match is true, `next` jumps all the rest of your statements and returns to the next iteration of the loop. Think about whether you need the `next` statement at all. If you do, you'd probably go well with: `if ( $string =~ /(<b>\w\|\.+\.zip<\/b>)/ ) { &do_something_with($1); # first next; # next }` [download] Concerning what to match, best you tell us in English what exactly you do mean to match? Is the pipe character an alternation? Or a literal pipe character? (write "`\\|`" then, see perlre) Cheers, Sören Update: corrected the typo ikegami pointed out.	[reply] [d/l]
Re^2: RegEx, $1, problem by ikegami (Patriarch) on Oct 28, 2004 at 15:03 UTC
Your `if` will only work if `!~` is changed to `=~`.	[reply] [d/l] [select]