protected function namespaceAndKey($key)
    {
        if ($this->hasNamespace($key)) {
            return explode($this->nsSeparator, $key, 2);
        }
        return ['default', $key];
    }
protected function namespaceAndKey($key)
    {
        if ($this->hasNamespace($key)) {
            return explode($this->nsSeparator, $key, 2);
        }
        return ['default', $key];
    }
protected function namespaceAndKey ( $ key ) { if ( $ this -> hasNamespace ( $ key ) ) { return explode ( $ this -> nsSeparator , $ key , 2 ) ; } return [ 'default' , $ key ] ; }
Return the namespace and key separately.

@param $key

@return array
Return the namespace and key separately .