combine_latest.cpp

#include <rpp/rpp.hpp>
#include <iostream>
 
std::ostream & operator<<(std::ostream & out, const std::tuple<int, int>& value)
{
    out << "{" << std::get<0>(value) << "," << std::get<1>(value) << "}";
    return out;
}
 
int main()
{
    rpp::source::just(rpp::schedulers::trampoline{}, 1, 2, 3)                      // source 1
        .combine_latest(rpp::source::just(rpp::schedulers::trampoline{}, 4, 5, 6)) // source 2
        .subscribe(
            [](const std::tuple<int, int> &v) { std::cout << "-" << v; },
            [](const std::exception_ptr&) {},
            []() { std::cout << "-|" << std::endl; });
    // source 1:   -1---2---3-|
    // source 2: -4---5---6-| (note that source 2 is subscribed earlier than source 1)
    // Output  : -{1,4}-{1,5}-{2,5}-{2,6}-{3,6}}-|
 
    rpp::source::just(1, 2, 3)                                  // source 1
        .combine_latest(
            [](int left, int right) { return left + right; },   // custom combiner
            rpp::source::just(4, 5, 6))                         // source 2
        .subscribe(
            [](int v) { std::cout << "-" << v; },
            [](const std::exception_ptr&) {},
            []() { std::cout << "-|" << std::endl; });
    // source 1:          -1---2---3-|
    // source 2: -4---5---6-| (note that source 2 is subscribed earlier than source 1)
    // Output  : -7-8-9-|
    return 0;
}