Hello. I'm trying to pattern-match an enum alongside a passed value in a loop, and have a mutable reference to a field in the enum. However, I can't seem to figure out the correct way to write this.

This is where I'm currently at:

use std::collections::HashMap;

enum Foo {
    One(HashMap<u8, u8>),
    Two,
}

impl Foo {
    fn bar(&mut self, a: u8) {
        for i in 0..2 {
            match (self, a) {
                (Foo::One(h), _) => {
                    h.get_mut(&0);
                }
                (Foo::Two, _) => {}
            }
        }
    }
}

fn main() {}

This code results in the compiler complaining about self being moved in the previous iteration of the loop.

Trying to do &self in the match statement makes h.get_mut() fail

Trying to do &mut self in the match statement fails because "the binding is already a mutable borrow"

What do?

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