| error[E0277]: the size for values of type `T` cannot be known at compilation time |
| --> $DIR/unsized-enum.rs:6:36 |
| | |
| LL | enum Foo<U> { FooSome(U), FooNone } |
| | - required by this bound in `Foo` |
| LL | fn foo1<T>() { not_sized::<Foo<T>>() } // Hunky dory. |
| LL | fn foo2<T: ?Sized>() { not_sized::<Foo<T>>() } |
| | - ^^^^^^ doesn't have a size known at compile-time |
| | | |
| | this type parameter needs to be `std::marker::Sized` |
| | |
| = help: the trait `std::marker::Sized` is not implemented for `T` |
| = note: to learn more, visit <https://doc.rust-lang.org/book/ch19-04-advanced-types.html#dynamically-sized-types-and-the-sized-trait> |
| help: you could relax the implicit `Sized` bound on `U` if it were used through indirection like `&U` or `Box<U>` |
| --> $DIR/unsized-enum.rs:4:10 |
| | |
| LL | enum Foo<U> { FooSome(U), FooNone } |
| | ^ - ...if indirection was used here: `Box<U>` |
| | | |
| | this could be changed to `U: ?Sized`... |
| |
| error: aborting due to previous error |
| |
| For more information about this error, try `rustc --explain E0277`. |
