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1. 

   stafil
   Member

   Hi all,

   I dont understand for this result.(maple r5 maple ide 12, win 8)

   my code

   uint16 courierNew9pt_BoldCharDescriptors[4][3] =
   {
   { 9, 13, 1560 } , // \
   { 9, 13, 1586 } , // ]
   { 9, 13, 1612 } , // ^
   { 9, 13, 1638 } , // _
   };

   void setup()
   {
   delay(5000);
   for(int i = 0; i< sizeof(courierNew9pt_BoldCharDescriptors)/sizeof(courierNew9pt_BoldCharDescriptors[0]); i++)
   {
   SerialUSB.print(i);
   SerialUSB.print(": ");
   SerialUSB.println(courierNew9pt_BoldCharDescriptors[i][2]);
   }

   }

   void loop()
   {

   }

   and my result:

   0: 1560
   1: 1612
   2: 1638
   3: 0

   I understand. thx

   Posted 2 years ago #
2. 

   bubulindo
   Member

   This is very strange indeed.

   I manage to get the correct result by deleting the comments on the initialization of your matrix.

   uint16 temp[4][3] =
   {
   { 9, 13, 1560 } ,
   { 9, 13, 1586 } ,
   { 9, 13, 1612 } ,
   { 9, 13, 1638 } ,
   };

   Really, really strange. It seems that this "// \" causes the next instruction to be ignored.
   I tried it here:

   for(int i = 0; i< 4; i++)
   {
   SerialUSB.print(i); // \
   SerialUSB.print(": ");
   SerialUSB.println(temp[i][2]); // ^
   }

   And had the same behavior.

   Does any of the compiler gurus here understand why this happens?

   Posted 2 years ago #
3. 

   mlundinse
   Member

   In C macros \ is used as a line continuation character.
   This is used to create long #defines and format them on several lines
   in the source file.

   In most C code new lines doesnt affect the compiler, just makes code
   more readable. The exception is the // comment that is effective until
   the end of the current line.

   So the // \ combination extends the comment to include the next line.

   Posted 2 years ago #
4. 

   stafil
   Member

   thx all, it is work fine

   Posted 2 years ago #

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