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# Error code E0642

Trait methods currently cannot take patterns as arguments.

Erroneous code example:

    #![allow(unused)]
    fn main() {
    trait Foo {
        fn foo((x, y): (i32, i32)); // error: patterns aren't allowed
                                    //        in trait methods
    }
    }

You can instead use a single name for the argument:

    #![allow(unused)]
    fn main() {
    trait Foo {
        fn foo(x_and_y: (i32, i32)); // ok!
    }
    }