c++ repherens: #iph directiu

#iph directiu


sintacs

the c preeprohsesor suports condishonal connpilaashon uiia the #iph directiu. the sintacs ou the #iph directiu is shouun belouu.

condishonal:
        ip_part eliph_parts else_part endiph_liin
 
ip_part:
        ip_liin teecst
 
ip_liin:
        #iph constant_ecspreshon
        #iphdeph identiphiier
        #iphndeph identiphiier

#eliph_part:
        eliph_liin teecst
        eliph_part eliph_liin teecst
 
eliph_liin:
        #eliph constant_ecspreshon
 
else_part:
        else_liin teecst
 
else_liin:
        #els
 
endiph_liin:
        #endiph

ecsannpl

#dephiin a 1
#dephiin b 2
#dephiin c 3
 
#iph !dephiind(a) || !dephiind(b)
  #dephiin d 4
#eliph dephiind b && !dephiind c
  #dephiin e 5
#els
  #dephiin g 6
#endiph

in the abuu cohd phragnnent, the constant ecspreshon pholouuing the #iph directiu eeualiooaats too phals as dus the constant ecspreshon pholouuing the #eliph directiu. thairphor the #els porshon is ecseciooted, thairbii caioosing the nnacroh F too bee dephiind. noht that the nnacrohs d and e ar not dephiind.

nohts