fork download
copy 
  1. #include <iostream>
  2. #include <queue>
  3. #include <functional>
  4. #include <utility>
  5. //using namespace std;
  6.  
  7. using Offset = int; // next frame, or "after previous Entry was done", ...
  8. using DeferredFn = std::function<void()>;
  9.  
  10. struct Entry {
  11. 	Entry (Offset o, DeferredFn f) : offset(o), func {std::move(f)} {}
  12. 	Offset offset;
  13. 	DeferredFn func;
  14. };
  15. class MsgQ {
  16. public:
  17. 	MsgQ () : _q() {}
  18. 	~MsgQ () {}
  19. 	void push (Offset offset, DeferredFn function) {
  20. 		_q.push(Entry{offset, std::move(function)});
  21. 	}
  22. 	bool process () {
  23. 		// example! In reality it reacts on e.offs somehow!
  24. 		if (!_q.empty()) {
  25. 			auto e = _q.front();
  26. 			e.func(); // execute
  27. 			_q.pop();
  28. 			return true;
  29. 		}
  30. 		return false; // Q empty!
  31. 	}
  32. private:
  33. 	std::queue<Entry> _q;
  34. };
  35.  
  36. int oapiFoo(int a, int b) { auto res = a+b; std::cout << "done " << res; return res; };
  37. void oapiBar(int x) { std::cout << "done " << x; };
  38.  
  39. int main() {
  40. 	int x = 1;
  41. 	int y = 2;
  42. 	int z = 0;
  43. 	MsgQ q;
  44. 	q.push(1, [x,y,&z](){ z = oapiFoo(x, y); });
  45. 	// ...
  46. 	y++; // the lambda captured 'y'-state before, so try to avoid it ;)
  47. 	// ...
  48. 	q.push(10, [](){ oapiBar(42); });
  49. 	// ...
  50. 	q.process();
  51. 	q.process();
  52. 	return 0;
  53. }
Success #stdin #stdout 0s 4248KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
done 3done 42
https://ideone.com/ldBmLW
language:
C++14 (gcc 8.3)
created:
3 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!