#!/usr/bin/perl
use strict;
use warnings;
use Devel::Peek qw( Dump );

while (my $data = <DATA>) {
chomp $data;
print Dump( $data );
if ($data == 2){print "->got 2\n"}
}

print "Enter a 2\n";
my $input = <>;
print Dump( $input );
if ($input == 2){print "->got 2\n"}

__DATA__
1
2
3
4