Getting the number of elements in std::array at compile time

Question

Is the following a valid C++ code, and why not?

std::array a1;
std::array a2;

It doesn\'t compile

Answer 1

You can use the same template-inference method as has always been used for C++98 array bound detection.

template
constant_integer array_size( const std::array& );

• Demo: http://ideone.com/R4k1vG

Make a nice macro wrapper and enjoy!

Many variations are also possible, such as:

• http://ideone.com/Hn46ei