struct Ctx; enum Callback { Fn(fn(&mut Ctx)), Boxed(Box<dyn FnOnce(&mut Ctx)>), } fn normal_fn(_: &mut Ctx) {} let closure_no_capture = |_: &mut Ctx| {}; let closure_with_capture = { let data = vec![]; move |_: &mut Ctx| drop(data) }; …

Well that shows that the design is flawed. There's no need for the enum whatsoever. Function pointers implement Fn*() traits by themselves. OP should simply be using Box<dyn FnMut(...)> for storing the function. (For fn items and non-capturing closures, the Self type will be zero-sized, so the Box …

Implement Into for enum CallbackWrapper (closure/simple fn)

help

ceweg27574 August 14, 2024, 7:06am 5

Thanks alot.

more info about when Box allocates

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Implement Into for enum CallbackWrapper (closure/simple fn)

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