No defines?

[Stewbond]

I'm told that defines are to be avoided in general. Why would the following be inappropriate?

//#define DEBUG

#ifdef DEBUG
cout << "..." << endl;
#endif 

[Null]

There's nothing wrong with your code. #defines are useful in some situations (eg. include guards: http://www.cplusplus.com/articles/Gw6AC542/ ) but can cause problems in some too, eg.:

#define PI 3.14

int main()
{
const int PI=3.14; // will become const int 3.14=3.14; which will not compile
}[/code

string PI="Pi is equal to 3.14";

#define PI 3

int main()
{
cout <<PI<<endl; // will print 3
}

[hanst99]

This whole "no define" stuff is basically mostly directed at practices like using defines as constants or inline functions

//#define square(x) x*x -- bad, use
template<typename T>
auto square(x) -> decltype(x*x)
{
 return x*x;
}
//instead

//#define PI = 3.14 -- bad, use
const float /*or double, or whatever*/ PI = 3.14;
//instead 

The reason being that macros actually replace text, and thus don't behave like you'd expect them too, and can also cause various unintended side effects.