How to reliably get size of C-style array?

Question

How do I reliably get the size of a C-style array? The method often recommended seems to be to use sizeof, but it doesn\'t work in the foo function

Answer 1

Now, you can use C++11's extent and rank.

By example:

#include 
#include 

int main()
{
  int a[][3] = {{1, 2, 3}, {4, 5, 6}};

  std::cout << "\nRank:           : " << std::rank::value;
  std::cout << "\nSize: [_here_][]: " << std::extent::value;
  std::cout << "\nSize: [][_here_]: " << std::extent::value;
  std::cout << "\nSize: [][]_here_: " << std::extent::value;
}

prints:

Rank:           : 2
Size: [_here_][]: 2
Size: [][_here_]: 3
Size: [][]_here_: 0