use strict;
my $str = '$t1 = "Disposizione n. 158 del 28.1.2012";
$t2 = "Disposizione n.66 del 15.1.2006";
$t3 = "Disposizione f_n_66 del 15.1.2001";
$t4 = "Disposizione numero 66 del 15.1.2018";
$t5 = "Disposizione nr. 66 del 15.1.2017";
$t6 = "Disposizione nr_66 del 15.1.2016";
$t7 = "Disposizione numero_66 del 15.1.2005";';
my $regex = qr/(?<![^\W_])n(?:r?[_.]|umero_?)\s*\K\d+/ip;
if ( $str =~ /$regex/g ) {
print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n";
# print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n";
# print "Capture Group 2 is $2 ... and so on\n";
}
# ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p'
# Named capture groups can be called via $+{name}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html