mirror of
https://github.com/rust-lang/rust.git
synced 2024-10-31 22:41:50 +00:00
20 lines
483 B
Rust
20 lines
483 B
Rust
// build-fail
|
|
|
|
trait ZeroSized: Sized {
|
|
const I_AM_ZERO_SIZED: ();
|
|
fn requires_zero_size(self);
|
|
}
|
|
|
|
impl<T: Sized> ZeroSized for T {
|
|
const I_AM_ZERO_SIZED: () = [()][std::mem::size_of::<Self>()]; //~ ERROR evaluation of `<u32 as ZeroSized>::I_AM_ZERO_SIZED` failed
|
|
fn requires_zero_size(self) {
|
|
let () = Self::I_AM_ZERO_SIZED;
|
|
println!("requires_zero_size called");
|
|
}
|
|
}
|
|
|
|
fn main() {
|
|
().requires_zero_size();
|
|
42_u32.requires_zero_size();
|
|
}
|