$re = '/(<\?=)
(
(
(?!
(htmlspecialchars|htmlentities|json_encode)
)
.
)*
[\$]{1,}
(.*)
)
(\?>)/ix';
$str = '<?= $lorem ?>
<?= _($lorem) ?>
<?= \'ipsumz\' ?>
<?= _(\'ipsum\') ?>
//Conditions ternaires
<?= ($a == $b) ? \'lorem\' : \'ipsum\' ?>
//Chaînes contenant un htmlspecialchars()
<?= \'lorem \' . htmlspecialchars(\'lorem ipsum\') ?>
//Chaînes contenant un htmlentities()
<?= htmlentities(\'lorem ipsum\') ?>';
$subst = "purify($2)";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php