array_keys

<?php                 ++$i;

            }

            if ($prefixedKeys) {

                $keys = array_keys($a);

                foreach ($prefixedKeys as $i => $k) {

                    $keys[$i] = $k;

                }

<?php             $a = [];



            if ($c->value) {

                foreach (array_keys($c->value) as $k) {

                    $keys[] = !isset($k[0]) || "\0" !== $k[0] ? Caster::PREFIX_VIRTUAL.$k : $k;

                }

<?php     private function getAvailableFormats(): array

    {

        return array_keys($this->descriptors);

    }

}

<?php     private function getSpecialVars()

    {

        foreach (array_keys($GLOBALS) as $var) {

            if ('GLOBALS' !== $var) {

                unset($GLOBALS[$var]);

            }