protected function argValue(&$out)
{
$s = $this->seek();
$keyword = null;
if (!$this->variable($keyword) || !$this->literal(':')) {
$this->seek($s);
$keyword = null;
}
if ($this->genericList($value, 'expression')) {
$out = [$keyword, $value, false];
$s = $this->seek();
if ($this->literal('...')) {
$out[2] = true;
} else {
$this->seek($s);
}
return true;
}
return false;
}