C++/Development/macro

Printing values in DEBUG mode.

<source lang="cpp">

1. include <iostream>

using namespace std;

1. define DEBUG
2. ifndef DEBUG
3. define PRINT(x)
4. else
5. define PRINT(x) \

  cout << #x << ":\t" << x << endl;

1. endif

enum BOOL { FALSE, TRUE } ; int main() {

  int x = 5;
  long y = 73898l;
  PRINT(x);
  for (int i = 0; i < x; i++)
  {
     PRINT(i);
  }
  PRINT (y);
  PRINT("Hi.");
  int *px = &x;
  PRINT(px);
  PRINT (*px);
  return 0;

}

 </source>

Using #define.

<source lang="cpp">

1. define DemoVersion
2. define DOS_VERSION 5
3. include <iostream>

using namespace std; int main() { cout << "Checking on the definitions of DemoVersion, DOS_VERSION and WINDOWS_VERSION...\n";

1. ifdef DemoVersion

  cout << "DemoVersion defined.\n";

1. else

  cout << "DemoVersion not defined.\n";

1. endif
2. ifndef DOS_VERSION

  cout << "DOS_VERSION not defined!\n";

1. else

  cout << "DOS_VERSION defined as: " << DOS_VERSION << endl;

1. endif
2. ifdef WINDOWS_VERSION

  cout << "WINDOWS_VERSION defined!\n";

1. else

  cout << "WINDOWS_VERSION was not defined.\n";

1. endif

cout << "Done.\n";
return 0;

}

 </source>