tests/ui/unsized-locals/by-value-trait-dyn-compatibility-rpass.rs


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pub trait Foo {
    fn foo(self) -> String;
}

struct A;

impl Foo for A {
    fn foo(self) -> String {
        format!("hello")
    }
}

fn main() {
    let x = *(Box::new(A) as Box<dyn Foo>); //~ERROR the size for values of type `dyn Foo` cannot be known at compilation time
    assert_eq!(x.foo(), format!("hello"));

    // I'm not sure whether we want this to work
    let x = Box::new(A) as Box<dyn Foo>;
    assert_eq!(x.foo(), format!("hello"));
}