    C++____________________________611

11.2.3  :  #if, #endif, #ifdef,
ftifndef. #else, #elif

      -
      .  
      -
.   ,  sizeof   -
;      ,    -
.

   #if      if. 
:  :

ttif 

 
ttendif

      .   -
    (),   ,   -
 #if   #endif .    
 (),      ,  .

 ,   ,   

defined 

defined  1,       -
 #define,   0   . ,  -
 :

ttif defined Debug && [defined MyConst

 
ftendif

   ,     

((define Debug
   

ttdefine MyConst
     

ftundef MyConst

 #if defined      
tifdef,   #if ! defined   #ifndef. , 

ttifdef Size
ftendif

Undefined Size
ttendif

.

I        -
    #elif ( else if    if) 
|ttelse ( else   if). ,  

ttif  1

  1
ftelif  2

  2

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