while, also loop, C++ (vc++)

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#include <iostream>
#include <future>
#include <functional>
#include <thread>
#include <chrono>

struct statement { std::function< void() > fn ; };

struct compound_statement { statement a ; statement b ; };

struct condition
{
    std::function< bool() > cond ;
    void operator, ( compound_statement cs ) const
    {
        auto future = std::async( std::launch::async, [&] { while( cond() ) cs.a.fn() ; } ) ;
        while( cond() ) cs.b.fn() ;
    }
};

compound_statement operator & ( statement a, statement b ) { return {a,b} ; }

template < typename FN > condition While( FN fn ) { return {fn} ; }
template < typename FN > statement Do( FN fn ) { return {fn} ; }
template < typename FN > statement Also( FN fn ) { return {fn} ; }

int main()
{
    using namespace std::this_thread ;
    using namespace std::literals ;

std::atomic<int> i {20} ;
    std::atomic<int> j {80} ;
    const auto condition = [&] { return i < j ; } ;
    const auto this_thing = [&] { std::cout << '1' << std::flush ; ++i ; sleep_for(100ms) ; } ;
    const auto something_else = [&] { std::cout << '2' << std::flush ; --j ; sleep_for(50ms) ; } ;

While(condition), Do(this_thing) & Also(something_else) ;
    
    std::cout << "\n\ni == " << i << "  j == " << j << '\n' ;
}

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Compilation time: 3,14 sec, absolute running time: 2,76 sec, absolute service time: 5,91 sec