public function prefixKey($prefix)
    {
        if (empty($this->key)) {
            $this->key = $prefix;
        } else {
            $this->key = $prefix . '.' . $this->key;
        }

        return $this;
    }
public function prefixKey($prefix)
    {
        if (empty($this->key)) {
            $this->key = $prefix;
        } else {
            $this->key = $prefix . '.' . $this->key;
        }

        return $this;
    }
public function prefixKey ( $ prefix ) { if ( empty ( $ this -> key ) ) { $ this -> key = $ prefix ; } else { $ this -> key = $ prefix . '.' . $ this -> key ; } return $ this ; }
Prefixes the currently set key with a dot-notation parent.

The (final) dot (.) should not be included in the prefix string.

@param string $prefix
@return $this
Prefixes the currently set key with a dot - notation parent .