@@ -108,7 +108,7 @@  | 
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| 108 | 108 | * @param string|null $detached_payload  | 
                                                        
| 109 | 109 | * @param int|null $recipient_index  | 
                                                        
| 110 | 110 | *  | 
                                                        
| 111 | - * @return bool  | 
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| 111 | + * @return boolean|null  | 
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| 112 | 112 | */  | 
                                                        
| 113 | 113 | private function verifySignatures(JWSInterface $jws, JWKSetInterface $jwk_set, $detached_payload = null, &$recipient_index = null)  | 
                                                        
| 114 | 114 |      { |