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# Error code E0224

A trait object was declared with no traits.

Erroneous code example:

    #![allow(unused)]
    fn main() {
    type Foo = dyn 'static +;
    }

Rust does not currently support this.

To solve, ensure that the trait object has at least one trait:

    #![allow(unused)]
    fn main() {
    type Foo = dyn 'static + Copy;
    }