- var_dump: documentation ( source)
<?php
$var = -9223372036854775808;
$var2 = ~PHP_INT_MAX;
$var3 = -9223372036854775807;
var_dump($var, $var2, $var3);
$var = 9223372036854775807;
$var2 = PHP_INT_MAX;
$var3 = ~(-9223372036854775808);
var_dump($var, $var2, $var3);