Executors

Executors are the basic building block for execution in C++ and fulfil a similar role for execution such as allocators for the containers in C++. Functions such as async, the parallel algorithms of the Standard Template Library, the then continuation of futures, the run methods of task blocks, or the post, dispatch, or defer calls of the Networking TS use them. Also, execution is a fundamental concern of programming there is no standardised way to perform an execution.

Here is the introductory example of the proposal P0761.

Various parallel_for implementations

void parallel_for(int facility, int n, function<void(int)> f) {
  if(facility == OPENMP) {
    #pragma omp parallel for
    for(int i = 0; i < n; ++i) {
      f(i);
    }
  }
else if(facility == GPU) {
  parallel_for_gpu_kernel<<<n>>>(f);
}
else if(facility == THREAD_POOL) {
  global_thread_pool_variable.submit(n, f);
  }
}

This parallel_for function has a few issues.

• A simple...