<?php
//dirname可指定目录级数
//intdiv整数整除
//define可以定义数组

echo dirname('/var/www/html/app/etc/config');
echo '<br/>';
echo dirname('/var/www/html/app/etc/config/');
echo '<br/>';
echo dirname('/var/www/html/app/etc/config.php');
echo '<br/>';
echo dirname('/var/www/html/app/etc/config.php', 2);
echo '<br/>';
echo dirname('/var/www/html/app/etc/config.php', 3);
echo '<br/>';

echo intdiv(5, 3);
echo '<br/>';
echo intdiv(-5, 3);
echo '<br/>';
echo intdiv(5, -2);
echo '<br/>';
echo intdiv(-5, -2);
echo '<br/>';

define('FRAMEWORK', [
    'version' => 1.2,
    'licence' => 'enterprise'
]);

echo FRAMEWORK['version'];
echo '<br/>';
echo FRAMEWORK['licence'];
echo '<br/>';

class App {
    const FRAMEWORK = [
        'version' => 1.2,
        'licence' => 'enterprise'
    ];
}

echo App::FRAMEWORK['version'];
echo '<br/>';
echo App::FRAMEWORK['licence'];
echo '<br/>';
?>

/var/www/html/app/etc
/var/www/html/app/etc
/var/www/html/app/etc
/var/www/html/app
/var/www/html
1
-1
-2
2
1.2
enterprise
1.2
enterprise