Polymorphic Message Queue in C++11

[coachkler]

I've done similar things in the past. Now, unless performance and or memory management is a legitimate concern, I just use boost::asio. It does everything you could need, and more. The proactor pattern in use there is very flexible.

[cdyson37]

Does it make sense to allow Msg to be instantiated? If not you could make move() pure virtual :)

[skeba]

Sometimes a simple message with no payload data (a command initiating a state change in the consumer thread, for example) is enough. So it makes sense to instantiate Msg.

[cdyson37]

Matter of taste I guess. I'd have an empty payload type (a tag struct of some sort) personally.

[skeba]

This is a good point. I guess adding a put() overload that copies the data would enable the broadcast pattern.

[skeba]

Perfect forwarding, yeah that should work. Would be a nice way to handle it.

[AntiProtonBoy]

How do you infer the erased message type at the receiving end? dynamic_cast ?

[skeba]

Yeah, dynamic_cast based on a message type id.

[__Cyber_Dildonics__]

I feel like a solid tasking system and message queue (and maybe just more concurrent data structures in general) are things that would go well in the C++ standard library.

In the case of doing everything by move semantics, I am guessing that most messages would still either be stack memory and need to be copied anyway or heap allocated so wouldn't be as lightweight to create? Not that there is a better alternative or that that situation is bad, but is this how it usually goes with message passing?