#include <xutility>
#include <iostream>

template <typename Ty>
struct Simple_Array
{
    Ty* data;
    const size_t size;

    Simple_Array(size_t size) :
        size(size),
        data(new Ty[size])
    {
    }

//  Throws an exception.
    template <class It>
    Simple_Array(It first, It last) :
        size(std::distance(first, last)),
        data(new Ty[size])
    {
        for (int i = 0; first != last; ++first, ++i)
            data[i] = *first;
    }

//  This version works without any problems.
/*  template <class It>
    Simple_Array(It first, It last) :
        Simple_Array(std::distance(first, last))
    {
        for (int i = 0; first != last; ++first, ++i)
            data[i] = *first;
    }*/
};

int main() {
    auto list = { 1, 2, 3, 4 };

    try {
        Simple_Array<int>(list.begin(), list.end());
    }
    catch (...) {
        std::cout << "Failed." << std::endl;
    }

    std::cin.get();

    return 0;
}