C++11 Range

C++11 standard brings the so called range-based for loop. It extends the syntax of for statement to allow iteration over a range of items:

int array = {1, 2, 3, 5, 7};
for (int i : array)
{
    // do something
}

This implementation adds range function that mimics the usage of Python's counterpart in for loops. It allows to use the new syntax to conveniently iterate over a range:

for (int i : iter::range(10))
{
    std::cout << i << '\n';
}

Usage

There are two overloads. First takes single stop parameter and allows iteration in range [0, stop). The second overload takes three parameters: start, stop, and step. The default value for step is 1.

#include "iter_range.h"
#include <iostream>

int main()
{
    for (int i : iter::range(10))
    {
        std::cout << i << ' ';
    }
    // this outputs '0 1 2 3 4 5 6 7 8 9 '

    for (int i : iter::range(2, 5))
    {
        std::cout << i << ' ';
    }
    // this outputs '2 3 4 '

    for (int i : iter::range(1, 17, 2))
    {
        std::cout << i << ' ';
    }
    // this outputs '1 3 5 7 9 11 13 15 '

    for (int i : iter::range(10, 3, -2))
    {
        std::cout << i << ' ';
    }
    // this outputs '10 8 6 4 '

    for (int i : iter::range(0, -10, -1))
    {
        std::cout << i << ' ';
    }
    // this outputs '0 -1 -2 -3 -4 -5 -6 -7 -8 -9 '

    for (int i : iter::range(0))
    {
        std::cout << i << ' ';
    }
    // this outputs ''
}

License

This project is released under MIT/X11 license, so feel free to do anything you like with it.