public function getCallback($prefix)
    {
        if ($this->isRegistered($prefix) && !$this->_callbacks[$prefix]['is_fallback']) {
            return $this->_callbacks[$prefix]['callback'];
        }

        if ($callback = $this->findUnregisteredCallback($prefix)) {
            return $callback;
        }

        if ($this->isRegistered($prefix)) {
            return $this->_callbacks[$prefix]['callback'];
        }

        return null;
    }
public function getCallback($prefix)
    {
        if ($this->isRegistered($prefix) && !$this->_callbacks[$prefix]['is_fallback']) {
            return $this->_callbacks[$prefix]['callback'];
        }

        if ($callback = $this->findUnregisteredCallback($prefix)) {
            return $callback;
        }

        if ($this->isRegistered($prefix)) {
            return $this->_callbacks[$prefix]['callback'];
        }

        return null;
    }
public function getCallback ( $ prefix ) { if ( $ this -> isRegistered ( $ prefix ) && ! $ this -> _callbacks [ $ prefix ] [ 'is_fallback' ] ) { return $ this -> _callbacks [ $ prefix ] [ 'callback' ] ; } if ( $ callback = $ this -> findUnregisteredCallback ( $ prefix ) ) { return $ callback ; } if ( $ this -> isRegistered ( $ prefix ) ) { return $ this -> _callbacks [ $ prefix ] [ 'callback' ] ; } return null ; }
get callback for the prefix

@return callback or NULL
get callback for the prefix