Spaceship Operator
Spaceship operator is an operator which reports if a value is larger, equal or smaller than another value. It returns 1, 0 or -1 in each case, respectively.
The spaceship operator may be replaced by a - minus sign, if the compared values are correct. It may also be replaced with !=, since -1 and 1 are both cast to true.
The spaceship operator got its name from its resemblance to a flying saucer. Battleship operator, or death star operator do not exist.
<?php
$a = 1;
$b = 3;
print $a <=> $b;
?>