Regular expression

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

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Re: Regular expression by McDarren (Abbot) on Jun 05, 2006 at 06:44 UTC
It would help if you said exactly what it is that you are trying to do. But I guess that you are trying to split a date into its components using a regular expression. Well, you can capture (and assign) multiple parts of your expression in one go. So something like this: `my ($year, $month, $day) = $maxdate =~ m/(\d+)-(\d+)-(\d+)/;` [download] Of course, with your sample you could do the same thing using split, eg: `my ($year, $month, $day) = split /-/, $maxdate;` [download] But if you want something more robust and reliable, that can deal with different date formats - then you should look at one of the Date parsing modules available on CPAN. Cheers, Darren :)	[reply] [d/l] [select]
Re: Regular expression by davido (Cardinal) on Jun 05, 2006 at 06:45 UTC
How about this? `my $maxdate = "2006-06-06"; my( $m_year, $m_month ) = split /-/, $maxdate;` [download] Sometimes it's about using the right tool for the task. split comes in handy. Dave	[reply] [d/l]
Re: Regular expression by GrandFather (Saint) on Jun 05, 2006 at 06:55 UTC
Things clean up somwhat when you change the substitute to a match and know that the match returns the list of captured strings in list context: `use strict; use warnings; my $maxdate = "2006-06-05"; my ($m_year, $m_month, $d_day) = $maxdate =~ m/(^\d+)\-(\d+)-(\d+)/; print "year: $m_year, Month: $m_month, Day: $d_day\n";` [download] Prints: `year: 2006, Month: 06, Day: 05` [download] DWIM is Perl's answer to Gödel	[reply] [d/l] [select]
Re: Regular expression by ioannis (Abbot) on Jun 05, 2006 at 08:28 UTC
Assuming the date is in fixed-length format, you could also use unpack(): `my $maxdate = "2006-06-06"; my ($m_year, $m_month) = unpack 'A4 x A2', $maxdate;` [download]	[reply] [d/l]
Re: Regular expression by ambrus (Abbot) on Jun 05, 2006 at 09:43 UTC
If you just want to get the year and month part of the date, try this: `use Date::Manip; my $maxdate = "2006-05-11"; my($m_year, $m_month) = UnixDate($maxdate, "%Y", "%m");` [download]	[reply] [d/l]