| #![crate_type="lib"] |
| |
| // rust-lang/rust#61631: The use of `Self` in the defaults of generic |
| // types in a *trait* definition are allowed. |
| // |
| // It *must* be accepted; we have used this pattern extensively since |
| // Rust 1.0 (see e.g. `trait Add<Rhs=Self>`). |
| trait Tnobound<P = Self> {} |
| |
| impl Tnobound for () { } |
| |
| // This variant is accepted at the definition site; but it will be |
| // rejected at every possible usage site (such as the one immediately |
| // below). Maybe one day we will attempt to catch it at the definition |
| // site, but today this is accepted due to compiler implementation |
| // limitations. |
| trait Tsized<P: Sized = [Self]> {} |
| |
| impl Tsized for () {} |
| //~^ ERROR the size for values of type `[()]` cannot be known at compilation time [E0277] |