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I'm having trouble knowing when to pass/store std::function objects by value or reference, or if I need to use move semantics somehow. I have a struct that stores two std::function objects: struct Control{ char key; std::function<void()> press; std::function<void()> release; Control(char key, std::function<void()> press, std::function<void()> release): key(key),press(press),release(release){} } I also have a class that contains a vector of these structs, and I'd like to initialize it in a function resembling this one: void Screen::init(Player& player){ this->controls.push_back(Control( 'W', [&player](){player.go(UP);}, [&player](){player.stop(UP);})); } I'd like to be able to pass lambda expressions directly to the Control constructor, and eventually do this repeatedly: void Screen::update(){ foreach (auto control : controls){ if(...) control.press(); else if (...) control.release(); } } I've encountered a lot of errors and crashes trying to implement this idea, so I need to know Should the std::function 's be stored by (const?) reference, or by value, taking into account they capture a reference? Should they be passed to the Control constructor by (const?) reference, or value, (or moved, somehow)? Is it alright to store the Controls by value in a vector this way, or will I need to use an alternative ( unique_ptr<Control> , etc.)? when I loop through the controls vector, should I be accessing them by value, or by reference? Assume that the Player& object is always in scope for Screen::update() .

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