Re: [boost] Interest in a small array count facility?

From: Gennaro Prota (gennaro_prota_at_[hidden])
Date: 2006-06-25 19:28:19

On Sun, 25 Jun 2006 17:43:26 -0400, David Abrahams
<dave_at_[hidden]> wrote:

>That somersault is easy enough (although I've forgotten what it was
>exactly, there's an easy workaround).

Indeed I found it at the first try :)

template <std::size_t n>
struct counter
{
  enum { n = n }; // yep :)

  template <typename t>
  static char(&count(t(*)[n]))[n];

}; 

#define COUNT_OF(x) \
 (sizeof counter<(sizeof x / sizeof x[0])>::count(&x))

PS: note the enum!

--Gennaro.