Cast to Boolean

<?php

$a = 10; // Integer
$b = 8.34; // Float
$c = 0; // Integer
$d = -1; // Integer
$e = 0.1; // Float
$f = “hello”; // String
$g = “”; // String
$h = true; // Boolean
$i = NULL; // null

$a = (bool) $a;
$b = (bool) $b;
$c = (bool) $c;
$d = (bool) $d;
$e = (bool) $e;
$f = (bool) $f;
$g = (bool) $g;
$h = (bool) $h;
$i = (bool) $i;

var_dump($a);
var_dump($b);
var_dump($c);
var_dump($d);
var_dump($e);
var_dump($f);
var_dump($g);
var_dump($h);
var_dump($i);

?>