all_of.cc

#include <iostream>
#include <type_traits>
#include <iterator>

template<typename InputIterator, typename Predicate>
bool all_of(InputIterator begin, InputIterator end, Predicate pred){
  static_assert(std::is_integral<typename std::result_of<Predicate(typename std::iterator_traits<InputIterator>::value_type)>::type>::value, "pred should return integral");
  while (begin != end){
    if(!pred(*begin++)) return false;
  }
  return true;
}

int main(int argc, char const* argv[])
{
  int dat1[] = {0,2,4,6,8};
  int dat2[] = {0,2,4,5,8};
  auto is_even = [](int i){return i % 2 == 0;};
  std::cout << all_of(dat1, dat1 + 5, is_even) << std::endl;
  std::cout << all_of(dat2, dat2 + 5, is_even) << std::endl;
  return 0;
}