PHP - using a namespace in another namespace -

i'm trying use files namespace inside 1 of own namespaces, it's not recognising exceptions defuse\crypto namespace.

i've checked files, , there stored in directory. can include autoloader no exceptions too.

what can cleanly use both namespaces in same file?

here's code:

namespace defuse\crypto;  $path = '/my/path/to/defusecrypto/autoloader'; require_once $path;  use \defuse\crypto\crypto; use \defuse\crypto\exception ex;  namespace mynamespace;  class myclass {     static function encrypt_key($key)     {         try         {             $ciphertext = crypto::encrypt($key, $privatekey);             return $ciphertext;         }         catch (ex\cryptotestfailedexception $ex)         {             return false;         }         catch (ex\cannotperformoperationexception $ex)         {             return false;         }     }      static function decrypt_key($key)     {         try         {             $decryptedkey = crypto::decrypt($key, $privatekey);             return $decryptedkey;         }         catch (ex\invalidciphertextexception $ex)         {             return false;         }         catch (ex\cryptotestfailedexception $ex)         {             return false;         }         catch (ex\cannotperformoperationexception $ex)         {             return false;         }     } } 

three options: either specify qualified (so absolute) namespace directly:

catch (\defuse\crypto\exception\cryptotestfailedexception $ex) 

or use relative namespace inside active namespace:

catch (exception\cryptotestfailedexception $ex) 

or have declare namespace under alias internal usage @henris. suggested above:

use defuse\crypto\exception ex; [...] catch (ex\cryptotestfailedexception $ex) 

in general nothing speaks against using multiple namespaces in 1 file, common. agree @henris. here not practice create separate namespace exceptions.