#defining constants in C++

Question

In various C code, I see constants defined like this:

#define T 100

Whereas in C++ examples, it is almost always:

const int T =         


        

Answer 1

Yes. The biggest reason is that preprocessor definitions do not obey the scoping rules of the language, polluting the global namespace, and worse -- they're even replaced in cases like

x->sameNameAsPreprocessorToken

Since preprocessor definitions are replaced at the textual level, other normal properties of variables do not apply - you can take the address of an int const, but not of a #define'd constant.

As noted by others, you also typically lose type safety and debugging ability.