[Solved] Dropping partially moved values after the moved values are dropped

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Is there a better way to fix this

Yes, but not in stable Rust. You need non-lexical lifetimes:

#![feature(nll)]

#[derive(Debug)]
struct Foo(u32);

fn get_foo(bar: &mut Foo) -> Option<&mut u32> {
    Some(&mut bar.0)
}

pub fn test() {
    let x = 5;
    let y = 6;
    let mut a = Foo(x);

    let b = get_foo(&mut a);

    if let Some(value) = b {
        *value = y;
    }

    println!("{:?}", a);
}

fn main() {}

Until then, just use the extra block.

Dropping the value of b doesn’t work either

drop has nothing to do with borrows.

See also:

  • Moved variable still borrowing after calling `drop`?
  • What are the options to end a mutable borrow in Rust?
  • Why is a borrow still held in the else block of an if let?
  • Rust borrow of a HashMap lasts beyond the scope it’s in?
  • How to end a borrow in a match or if let expression?
  • Borrow checker and function arguments in Rust, correct or over zealous?

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solved Dropping partially moved values after the moved values are dropped