Streams

gistfile1.cpp

#include <iostream>

using namespace std;

int foo()
{
  auto flatMap = [](auto f, auto s) { return [=](auto k) { return s([=](auto x) { f(x)(k); }); }; };
  auto map = [](auto f, auto s) { return [=](auto k) { s([=](auto x) { k(f(x)); });  }; };
  auto filter = [](auto p, auto s) { return [=](auto k) { s([=](auto x) { if(p(x)) k(x); });  }; };
  auto sum = [](auto k) { int sum = 0; k([&](int x) { sum += x; }); return sum; };
  auto length = [](auto k) { int count = 0; k([&](int x) { count++; }); return count; };
  auto source = [](auto k) {  for(int i = 0; i <= 35; i++) k(i); };

    
  auto result = sum(map([](int x) { return x + 1; }, source));
  
  return result;
}

int main()
{
  cout << foo() << endl;
  return 0;
}