Supported Versions: PHP 4, PHP 5, PHP 7, PHP 8
Fetch a key from an array
<?php key(array|object $array): int|string|null
<?php             if (str_contains($identifier, "@anonymous\0")) {

                $this->value = $identifier = preg_replace_callback('/[a-zA-Z_\x7f-\xff][\\\\a-zA-Z0-9_\x7f-\xff]*+@anonymous\x00.*?\.php(?:0x?|:[0-9]++\$)[0-9a-fA-F]++/', function ($m) {

                    return class_exists($m[0], false) ? (get_parent_class($m[0]) ?: key(class_implements($m[0])) ?: 'class').'@anonymous' : $m[0];

                }, $identifier);

            }
<?php         if (isset($a[Caster::PREFIX_PROTECTED.'message']) && str_contains($a[Caster::PREFIX_PROTECTED.'message'], "@anonymous\0")) {

            $a[Caster::PREFIX_PROTECTED.'message'] = preg_replace_callback('/[a-zA-Z_\x7f-\xff][\\\\a-zA-Z0-9_\x7f-\xff]*+@anonymous\x00.*?\.php(?:0x?|:[0-9]++\$)[0-9a-fA-F]++/', function ($m) {

                return class_exists($m[0], false) ? (get_parent_class($m[0]) ?: key(class_implements($m[0])) ?: 'class').'@anonymous' : $m[0];

            }, $a[Caster::PREFIX_PROTECTED.'message']);

        }