in dispenso/detail/pipeline_impl.h [356:361]
auto makePipes(ConcurrentTaskSet& tasks, Stage0&& sCur, Stage1&& sNext, Stages&&... sFollowing) {
auto pipe = makePipesHelper<ResultOf<Stage0>>(
tasks, std::forward<Stage1>(sNext), std::forward<Stages>(sFollowing)...);
return Pipe<StageClass::kGenerator, Stage0, decltype(pipe)>(
tasks, std::forward<Stage0>(sCur), std::move(pipe));
}