my $a = 3.0;
my $b = '3.0';

my $stringCompareResult = $a eq $b?'true':'false';
my $numberCompareResult = $a == $b?'true':'false';
print ("\$stringCompareResult: $stringCompareResult\n");
print ("\$numberCompareResult: $numberCompareResult\n");

##</code><code>##

$stringCompareResult: false<br>
$numberCompareResult: true<br>

##</code><code>##

sub is_numeric {
  ($_[0] & ~ $_[0]) eq "0";
}