Online PHP editor | output for 9KaUe

@ 2014-03-20T15:41:34Z

<?php
//$oldLocale = setlocale(LC_ALL, 0);
//setLocale(LC_ALL, 'en_US.UTF8');
$firstName='kéké';
$lastName='kéké';

//$firstName = iconv('UTF-8', 'ASCII//TRANSLIT//IGNORE', $firstName);
//$lastName  = iconv('UTF-8', 'ASCII//TRANSLIT//IGNORE', $lastName);

//setLocale(LC_ALL, $oldLocale);

$firstName = mb_strstr($firstName,'àáâãäçèéêëìíîïñòóôõöùúûüýÿÀÁÂÃÄÇÈÉÊËÌÍÎÏÑÒÓÔÕÖÙÚÛÜÝ',
'aaaaaceeeeiiiinooooouuuuyyAAAAACEEEEIIIINOOOOOUUUUY');
$lastName = mb_strstr($lastName,'àáâãäçèéêëìíîïñòóôõöùúûüýÿÀÁÂÃÄÇÈÉÊËÌÍÎÏÑÒÓÔÕÖÙÚÛÜÝ',
'aaaaaceeeeiiiinooooouuuuyyAAAAACEEEEIIIINOOOOOUUUUY');

$username  = strtolower(
    substr(
        preg_replace('/\s/', '', $firstName[0].$lastName),
                0, 8
        )
    );

echo $username;

Output for 8.3.0 - 8.3.6: Warning: Trying to access array offset on false in /in/9KaUe on line 19
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18: Warning: Trying to access array offset on value of type bool in /in/9KaUe on line 19
Output for 7.4.0 - 7.4.33: Notice: Trying to access array offset on value of type bool in /in/9KaUe on line 19
Output for 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6: Fatal error: Call to undefined function mb_strstr() in /in/9KaUe on line 12
Process exited with code 255.
Output for 4.4.5 - 4.4.9: Fatal error: Call to undefined function: mb_strstr() in /in/9KaUe on line 12
Process exited with code 255.
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.4: Fatal error: Call to undefined function: mb_strstr() in /in/9KaUe on line 12
Process exited with code 255.
Output for 4.3.0 - 4.3.1: Fatal error: Call to undefined function: mb_strstr() in /in/9KaUe on line 12

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