How can I match a multi-line regexp?

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Re: How can I match a multi-line regexp?⭐ by nuance (Hermit) on Jun 14, 2000 at 02:49 UTC
It's hard to be certain exactly what you're looking for, I'm going to assume that you are looking for a specific keyword and that the text following is fairly free form. `my $keyword = "BASKET"; $data =~ /^($keyword\n\n.+)$/m;` [download] This looks for the keyword followed by two newlines, and whatever else is on that line. It will not match if the line following the two newlines is blank. The m at the end of the pattern specifies multi-line matching i.e. the $ will match before any newline, not just at the end of the string. This answer assumes that $data contains all of the text you are trying to search, not just a single line.	[reply] [d/l]
Re: How can I match a multi-line regexp? by athomason (Curate) on Jun 14, 2000 at 02:35 UTC
You need to tell the regex engine to treat your scalar as a multiline string with the /m option; otherwise it won't attempt to match across newlines. For instance, `$_ = "bunch of stuff\nwith target\nstring inside"; print "Found" if /target\nstring/m;` [download]	[reply] [d/l]
Re: How can I match a multi-line regexp? by wesal (Initiate) on Aug 11, 2010 at 20:50 UTC
To overcome the limitation with the quick in-place edit not working on matching the first-line you can remove the -p and do it yourself like: perl -i.bak -e 'undef $/; $_=<>; s/line1\nline1/new content/g; print' files ..	[reply]
Re: How can I match a multi-line regexp? by markjugg (Curate) on May 30, 2002 at 03:08 UTC
If you want to do a quick in-place edit of a bunch of files, you can use this syntax: `perl -pi.bak -e 'undef $/; s/line1\nline2/new content/' files ..` [download] This will create ".bak" files for every file it operates on. NOTE that it won't find any matches on the first line. If someone knows another one-liner that also matches on the first line, I'm interested to see it. :)	[reply] [d/l]
Re: Answer: How can I match a multi-line regexp? by Anonymous Monk on Jul 17, 2003 at 16:31 UTC
what is the effect of undef $/; ?	[reply]