mirror of
https://github.com/rust-lang/rust.git
synced 2024-12-11 16:15:03 +00:00
42 lines
818 B
Rust
42 lines
818 B
Rust
// Forbid assignment into a dynamically sized type.
|
|
|
|
struct Fat<T: ?Sized> {
|
|
f1: isize,
|
|
f2: &'static str,
|
|
ptr: T
|
|
}
|
|
|
|
#[derive(PartialEq,Eq)]
|
|
struct Bar;
|
|
|
|
#[derive(PartialEq,Eq)]
|
|
struct Bar1 {
|
|
f: isize
|
|
}
|
|
|
|
trait ToBar {
|
|
fn to_bar(&self) -> Bar;
|
|
fn to_val(&self) -> isize;
|
|
}
|
|
|
|
impl ToBar for Bar1 {
|
|
fn to_bar(&self) -> Bar {
|
|
Bar
|
|
}
|
|
fn to_val(&self) -> isize {
|
|
self.f
|
|
}
|
|
}
|
|
|
|
pub fn main() {
|
|
// Assignment.
|
|
let f5: &mut Fat<dyn ToBar> = &mut Fat { f1: 5, f2: "some str", ptr: Bar1 {f :42} };
|
|
let z: Box<dyn ToBar> = Box::new(Bar1 {f: 36});
|
|
f5.ptr = Bar1 {f: 36};
|
|
//~^ ERROR mismatched types
|
|
//~| expected `dyn ToBar`, found `Bar1`
|
|
//~| expected trait object `dyn ToBar`
|
|
//~| found struct `Bar1`
|
|
//~| ERROR the size for values of type
|
|
}
|