                 sysUnexpectedDesc = NSLocalizedString("unexpected end of input", comment: "Error messages.")
                 
             } else {
-            
+                
                 sysUnexpectedDesc = unexpectedMsg + " " + firstMsg
                 
             }

        
    }
    
}

extension SequenceType where Generator.Element == String {

        }
        
        // Unexpected messages.
        let unexpectedDesc = formatMessages(unexpected, havingType: unexpectedMsg)
        
        // Expected messages.
        let expectingMsg = NSLocalizedString("expecting", comment: "Error messages.")
        let expectedDesc = formatMessages(expected, havingType: expectingMsg)
        
        // Generic messages.
        let genericDesc = formatMessages(generic, havingType: "")
        
        let descriptions = [sysUnexpectedDesc, unexpectedDesc, expectedDesc, genericDesc]
        return descriptions.removingDuplicatesAndEmpties().joinWithSeparator("\n")
        
    }
    
    /// Initializes from a source position and an array of messages.
    init(position: SourcePosition, messages: [Message]) {
        
