448  12.  - 

    trip_announcement " "  -
    C++.     -
,    ,    
  .    
,     ,    
 . ,     proposition   .
  12.3    peformance_statement.

//  12.3.   per?ormance_statement

class performance_statement :

public proposition<performance_statement>{

//. . .

int Bays ;

float Sales;

float PerHour;

public:

bool operator() (void);

bool operator==(const performance_statement &X) const;

void bays(int X) ;

int bays (void) ;

float sales(void) ;

void sales(float X) ;

float perHour(void);

void perHour(float X) ;

friend bool operator||(bool X,per?ormance_statement &Y) ;

friend bool operator&&(bool X,perfonnance_statement &Y) ;

//. . .
};

   ,       
proposition .

class perfonnance_statement :

public proposition<performance_statement> {...}

    proposition    
 per?ormance_statement.  performance_statement  
    ,   
( )      .     -
  ,      ,   -
.       :

Bays

Sales

PerHour

 ,  "  1    300 . .,
 10   ,     4",  
    performance_statement. ,    
  ,    ,    
 proposition.  . 12.2  UML- 
trip_announcement  performance_statement.    
   .