Timing a function with <chrono>

chrono_function_timing.cpp

#include <iostream>
#include <thread>
#include <chrono>

void really_long_function()
{
    using namespace std::chrono;
    
    // Very cool user defined literals for duration representation
    std::this_thread::sleep_for(3000ms);
}

int main(int argc, const char * argv[])
{
    using namespace std::chrono;
    
    auto begin_time = steady_clock::now();
    
    really_long_function();
    
    auto end_time = steady_clock::now();
    
    auto function_time = duration_cast<milliseconds>(end_time - begin_time);
    
    std::cout << function_time.count() << "ms" << std::endl;
    
    return 0;
}