basics/tasksbug.hpp

The following code example is taken from the book
C++ Move Semantics - The Complete Guide by Nicolai M. Josuttis, Leanpub, 2020
The code is licensed under a Creative Commons Attribution 4.0 International License.

---

// raw code

#include <array>
#include <thread>

class Tasks {
private:
  std::array<std::thread,10> threads;  // array of threads for up to 10 tasks
  int numThreads{0};                   // current number of threads/tasks
public:
  Tasks() = default;

  // pass a new thread:
  template <typename T>
  void start(T op) {
    threads[numThreads] = std::thread{std::move(op)};
    ++numThreads;
  }
  //...

  // OOPS: enable default move semantics:
  Tasks(Tasks&&) = default;
  Tasks& operator=(Tasks&&) = default;

  // at the end wait for all started threads:
  ~Tasks() {
    for (int i = 0; i < numThreads; ++i) {
      threads[i].join();
    }
  }
};