$rv = \$var;         # reference to $var
$num = 0+\$var;      # NUMERICAL value of $rv
                     # ($num could conceivably occur in your
                     # program "by chance")

ref $rv or die;      # ASSERT: $rv is a reference
!(ref $num) or die;  # ASSERT: $num is NOT a reference

print $rv == $num, $/;
                     # Prints "1": a reference equals a
                     # number.