Is it possible to pass a function receiving self as a parameter of a function of self?

Question

Can I pass a function of an instance as a parameter to a function of the same instance, or do I have to pull the passed function out of the instance?

So, basically, does something like this work:

impl Some_Type {
    fn some_fn(&self, value: u32) -> u32 {
        value
    }

    fn some_other_fn(&self, value: u32, fn: &dyn Fn(&Self, u32) -> u32) -> u32 {
        fn(value)
    }
}

fn main() {
    let instance = Some_Type::new();
    let fourty_two = instance.some_other_fn(42, &instance.some_fn);
}

Or do I have to write it like this:

impl Some_Type {
    fn some_other_fn(&self, value: u32, fn: &dyn Fn(&Self, u32) -> u32) -> u32 {
        fn(value)
    }
}

fn some_fn(&Some_Type, value: u32) -> u32 {
    value
}

fn main() {
    let instance = Some_Type::new();
    let fourty_two = instance.some_other_fn(42, &some_fn);
}

Answer 1

I found a solution myself. One can write

fn main() {
    let instance = Some_Type::new();
    let fourty_two = instance.some_other_fn(42, &Some_Type.some_fn);
}

and pass &self to fn inside Some_Type.some_other_fn in the first example.