if($tmp2){
  if($tmp2 =~ m/'/){ 
 ...

##</code><code>##

use strict;
use warnings;

my $string = "Hello world!";

$string =~ m/(H\w+)\s(\w+)/; # This match succeeds.

print $2, "\n";

$string =~ /(\d)(\d)/;  # This match fails.

print $2, "\n";

##</code><code>##

world
world

##</code><code>##

my $tmp2 = $var;  # Because of bad logic we don't know
                  # if $var is defined, thus don't know if
                  # $tmp2 is defined.

if ( defined( $tmp2 ) and $tmp2 =~ m/regex/ ) {
    # Do your stuff.
}