Neatest way to loop over a range of integers

Question

Since C++11 introduced the range-based for loop (range-based for in c++11), what is the neatest way to express looping over a range of integers?

Instead of

for (int i=0; i<n; ++i) 

I'd like to write something like

for (int i : range(0,n)) 

Does the new standard support anything of that kind?

Update: this article describes how to implement a range generator in C++11: Generator in C++

Answer 1

While its not provided by C++11, you can write your own view or use the one from boost:

#include <boost/range/irange.hpp> #include <iostream>  int main(int argc, char **argv) {     for (auto i : boost::irange(1, 10))         std::cout << i << "\n"; } 

Moreover, Boost.Range contains a few more interesting ranges which you could find pretty useful combined with the new for loop. For example, you can get a reversed view.

Answer 2

The neatest way is still this:

for (int i=0; i<n; ++i) 

I guess you can do this, but I wouldn't call it so neat:

#include <iostream>  int main() {   for ( auto i : { 1,2,3,4,5 } )   {     std::cout<<i<<std::endl;   } }