Hi everyone, I have a question related to regular expression and below are 2 code snippets. Can you please advise why they give diffferent output? What is wrong with code snippet 2 ?

Code Snippet 1

#!/usr/bin/perl
use re qw(eval);

my $pattern1;
my $str1 = "RS";

$pattern1 = qr{(?<P_ROOTCODE>.*)(?{ push(@rc1, ${^MATCH}) })\K(?{ $p_r
+ootcode = "@rc1" })(?<DAY1>[0-9])(?{ push(@rc2, ${^MATCH}) })(?<P_MON
+_CODE>[A-Z])(?{ push(@rc3, ${^MATCH}) })$}; 

$str1 =~ m/$pattern1/;

print "Value of p_rootcode in Pattern 1 is : $p_rootcode\n";

[download]

Code Snippet 2

#!/usr/bin/perl
use re qw(eval);

my $pattern2;
my $str2 = "RS";

$pattern2 = qr{(?<P_ROOTCODE>.*)(?{ push(@rc1, ${^MATCH}) })\K(?{ $p_r
+ootcode = "@rc1" })(?<DAY1>[0-9])(?{ push(@rc2, ${^MATCH}) })(?<P_MON
+_CODE>[A-Z])(?{ push(@rc3, ${^MATCH}) })(?<P_NEW_MON_CODE>[A-Z])(?{ p
+ush(@rc4, ${^MATCH}) })$};

$str2 =~ m/$pattern2/;

print "Value of p_rootcode in Pattern 2 is : $p_rootcode\n";

[download]

In reply to Question on Regular Expression by sjain

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