Obtaining a pointer to the end of an array

Question

I use the following template to obtain a pointer pointing after the last element of an array:

template 
T* end_of(T (&array)[n])
         


        

Answer 1

You need a const version too. However, as far as I know, there's no actual problems with that approach- I see it used commonly.

Answer 2

Your proposal is not necessarily evaluated at compile time, it depends on optimisation. The following is calculated at compile time:

template <typename T, size_t N> char (&array(T(&)[N]))[N];

int main()
{
  int myArray[10];

  std::cout << sizeof array(myArray) << std::endl;

  return 0;
}

It works by creating an array type of char which is the same number of elements as the given array. sizeof always returns size in number of chars.

Answer 3

The only problem i see is that if you ever don't know the length at compile time, your template won't know what to put in there. So you'd have to say test+x or something anyway, and now you have two different ways to do the same thing.

Personally i'd rather just use a vector<int> and thus have end() already defined for me. If you ever need the array, it's available as &v[0].