> Is this all guaranteed to work also in a multithreaded environment? Yes. > How efficient is the garbage collector, and are there pauses? Not very efficient

> Is this all guaranteed to work also in a multithreaded environment? Yes. > How efficient is the garbage collector, and are there pauses? Not very efficient, and there might be pauses if you are not careful. Now if your closure doesn't escape (just a local function + context) it won't use the GC. So you can use delegates in @nogc code.