<span class="Apple-style-span" style="font-family: 'Times New Roman'; font-size: 16px; "><div style="margin-top: 8px; margin-right: 8px; margin-bottom: 8px; margin-left: 8px; font: normal normal normal small/normal arial; ">
<div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">I am writing a regex to test for valid dates in YYYY-MM-DD format.</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">Using this regex in a perl test program I get positive results for all dates for the next 365 days. </span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">Regex Coach however failes to match some such as '2010-06-30'. I assume this is because of the order of the alternations and the regex wanting to match a sub-pattern as quickly as possible. I can resolve the issue in The Regex Coach by adding () around the month and year patterns.</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small; "><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">I would like to know why there is a difference between my Perl program and Regex Coach. Could this be implementation dependent. Both my program and its output are below.</span></font></div>
<div><font class="Apple-style-span" face="'courier new'" size="2"><span class="Apple-style-span" style="font-size: 10px;"><br></span></font></div><div><font class="Apple-style-span" face="'courier new'" size="2"><span class="Apple-style-span" style="font-size: 10px;">I tend to think that The Regex Coach got this right.</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small; "><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">(?# regex in The Regex Coach)</span></font></div>
<div><b><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> [123456789]\d\d\d- # year</span></font></b></div>
<div><b><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> (?: </span></font></b></div>
<div><b><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> (?:0[13578]|10|12 - [012][123456789]|10|20|30|31) | # Months with 31 days</span></font></b></div>
<div><b><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> (?:0[469]|11 - [012][123456789]|10|20|30 ) | # Months with 30 days </span></font></b></div>
<div><b><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> (?:02 - [012][12345678]||10|20|19 ) # Febuary</span></font></b></div>
<div><b><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> )</span></font></b></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br>
</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">### perl Test program</span></font></div><div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">#!/iw-home/teamsite/iw-perl/bin/iwperl</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">use strict;</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">use warnings;</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">use Carp;</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">use Getopt::Long;</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">use Pod::Usage;</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">use Cwd;</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">use Date::Calc qw(:all);</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">my $dateregex = qr{</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> [123456789]\d\d\d- # year</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> (?: </span></font></div><div>
<font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> (?:0[13578]|10|12 - [012][123456789]|10|20|30|31) | # Months with 31 days</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> (?:0[469]|11 - [012][123456789]|10|20|30 ) | # Months with 30 days </span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> (?:02 - [012][12345678]||10|20|19 ) # Febuary</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> )</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">}smx;</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">sub testdate {</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> my ($d) = (@_);</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> print "$d";</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> if ( $d =~ m{$dateregex}smx ) {</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> print "okay\n";</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> }</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> else {</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> print "\n";</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> croak "broken";</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> }</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">}</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">foreach my $d ( 1 .. 365 ) {</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> my ( $year, $month, $day, $hour, $min, $sec, $doy, $dow, $dst ) =</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> System_Clock();</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> ( $year, $month, $day, $hour, $min, $sec ) =</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> Add_Delta_DHMS( $year, $month, $day, '0', '0', '0', "$d", '0', '0', '0' );</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br></span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> my $td = sprintf( "%4d-%02d-%02d", $year, $month, $day );</span></font></div>
<div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"> testdate("$td");</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;"><br>
</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">}</span></font></div><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-size: small;">exit;</span></font></div>
<div><br></div><div><br></div><div>##OUTPUT</div><div><div>2009-08-03okay</div><div>2009-08-04okay</div><div>2009-08-05okay</div><div>2009-08-06okay</div><div>2009-08-07okay</div><div>2009-08-08okay</div><div>2009-08-09okay</div>
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<div>2010-01-01okay</div><div>2010-01-02okay</div><div>2010-01-03okay</div><div>2010-01-04okay</div><div>2010-01-05okay</div><div>2010-01-06okay</div><div>2010-01-07okay</div><div>2010-01-08okay</div><div>2010-01-09okay</div>
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<div>2010-04-01okay</div><div>2010-04-02okay</div><div>2010-04-03okay</div><div>2010-04-04okay</div><div>2010-04-05okay</div><div>2010-04-06okay</div><div>2010-04-07okay</div><div>2010-04-08okay</div><div>2010-04-09okay</div>
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<div>2010-05-25okay</div><div>2010-05-26okay</div><div>2010-05-27okay</div><div>2010-05-28okay</div><div>2010-05-29okay</div><div>2010-05-30okay</div><div>2010-05-31okay</div><div>2010-06-01okay</div><div>2010-06-02okay</div>
<div>2010-06-03okay</div><div>2010-06-04okay</div><div>2010-06-05okay</div><div>2010-06-06okay</div><div>2010-06-07okay</div><div>2010-06-08okay</div><div>2010-06-09okay</div><div>2010-06-10okay</div><div>2010-06-11okay</div>
<div>2010-06-12okay</div><div>2010-06-13okay</div><div>2010-06-14okay</div><div>2010-06-15okay</div><div>2010-06-16okay</div><div>2010-06-17okay</div><div>2010-06-18okay</div><div>2010-06-19okay</div><div>2010-06-20okay</div>
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<div>2010-06-30okay</div><div>2010-07-01okay</div><div>2010-07-02okay</div><div>2010-07-03okay</div><div>2010-07-04okay</div><div>2010-07-05okay</div><div>2010-07-06okay</div><div>2010-07-07okay</div><div>2010-07-08okay</div>
<div>2010-07-09okay</div><div>2010-07-10okay</div><div>2010-07-11okay</div><div>2010-07-12okay</div><div>2010-07-13okay</div><div>2010-07-14okay</div><div>2010-07-15okay</div><div>2010-07-16okay</div><div>2010-07-17okay</div>
<div>2010-07-18okay</div><div>2010-07-19okay</div><div>2010-07-20okay</div><div>2010-07-21okay</div><div>2010-07-22okay</div><div>2010-07-23okay</div><div>2010-07-24okay</div><div>2010-07-25okay</div><div>2010-07-26okay</div>
<div>2010-07-27okay</div><div>2010-07-28okay</div><div>2010-07-29okay</div><div>2010-07-30okay</div><div>2010-07-31okay</div><div>2010-08-01okay</div><div>2010-08-02okay</div></div></div></div></div></span>