In the previous post we looked at a simple multithreaded task executor that behaves roughly like its Python standard library counterpart. The biggest missing feature was being able to return values from run tasks via future objects. In a fully dynamic language like Python this is fairly straightforward, whereas in a language with static typing, such as C++, things are trickier.The simplest solution is merely to make your Executor class a template, parameterized by the function you want to run. The obvious downside is code bloat. If your program has an Executor<Foo> and Executor<Bar>, all of their code is duplicated...