Getting the size of member variable

Question

If there is a POD structure, with some member variables, for example like this:

struct foo
{
   short a;
   int b;
   char c[50];
   // ...
};

Answer 1

You can create macro wrapper of what @Erik suggested as:

#define SIZE_OF_MEMBER(cls, member) sizeof( ((cls*)0)->member )

And then use it as:

cout << SIZE_OF_MEMBER(foo, c) << endl;

Output:

50

Demo : http://www.ideone.com/ZRiMe