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# Error code E0009

#### Note: this error code is no longer emitted by the compiler.

In a pattern, all values that don't implement the `Copy` trait have to be bound the same way. The goal here is to avoid binding simultaneously by-move and by-ref.

This limitation may be removed in a future version of Rust.

Erroneous code example:

    #![allow(unused)]
    #![feature(move_ref_pattern)]

    fn main() {
    struct X { x: (), }

    let x = Some((X { x: () }, X { x: () }));
    match x {
        Some((y, ref z)) => {}, // error: cannot bind by-move and by-ref in the
                                //        same pattern
        None => panic!()
    }
    }

You have two solutions:

Solution #1: Bind the pattern's values the same way.

    #![allow(unused)]
    fn main() {
    struct X { x: (), }

    let x = Some((X { x: () }, X { x: () }));
    match x {
        Some((ref y, ref z)) => {},
        // or Some((y, z)) => {}
        None => panic!()
    }
    }

Solution #2: Implement the `Copy` trait for the `X` structure.

However, please keep in mind that the first solution should be preferred.

    #![allow(unused)]
    fn main() {
    #[derive(Clone, Copy)]
    struct X { x: (), }

    let x = Some((X { x: () }, X { x: () }));
    match x {
        Some((y, ref z)) => {},
        None => panic!()
    }
    }