src/SecureString.php
protected function pushString(&$str, $item) {
        if ($str) {
            $str .= static::SEP;
        }
        $str .= implode(static::SEP, (array)$item);
    }
protected function pushString(&$str, $item) {
        if ($str) {
            $str .= static::SEP;
        }
        $str .= implode(static::SEP, (array)$item);
    }
Pushes a string on to the end of an encoded secure string.

@param string &$str The main string to push to.
@param string|array $item The string or array of strings to push on to the end of {@link $str}.