rust/tests/ui/object-safety/object-safety-issue-22040.stderr

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error[E0038]: the trait `Expr` cannot be made into an object
--> $DIR/object-safety-issue-22040.rs:12:23
|
LL | elements: Vec<Box<dyn Expr + 'x>>,
| ^^^^^^^^^^^^^ `Expr` cannot be made into an object
|
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/object-safety-issue-22040.rs:5:21
|
LL | trait Expr: Debug + PartialEq {
| ---- ^^^^^^^^^ ...because it uses `Self` as a type parameter
| |
| this trait cannot be made into an object...
= help: only type `SExpr<'x>` implements the trait, consider using it directly instead
error[E0038]: the trait `Expr` cannot be made into an object
--> $DIR/object-safety-issue-22040.rs:38:16
|
LL | let a: Box<dyn Expr> = Box::new(SExpr::new());
| ^^^^^^^^ `Expr` cannot be made into an object
|
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/object-safety-issue-22040.rs:5:21
|
LL | trait Expr: Debug + PartialEq {
| ---- ^^^^^^^^^ ...because it uses `Self` as a type parameter
| |
| this trait cannot be made into an object...
= help: only type `SExpr<'x>` implements the trait, consider using it directly instead
error[E0038]: the trait `Expr` cannot be made into an object
--> $DIR/object-safety-issue-22040.rs:40:16
|
LL | let b: Box<dyn Expr> = Box::new(SExpr::new());
| ^^^^^^^^ `Expr` cannot be made into an object
|
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/object-safety-issue-22040.rs:5:21
|
LL | trait Expr: Debug + PartialEq {
| ---- ^^^^^^^^^ ...because it uses `Self` as a type parameter
| |
| this trait cannot be made into an object...
= help: only type `SExpr<'x>` implements the trait, consider using it directly instead
error: aborting due to 3 previous errors
For more information about this error, try `rustc --explain E0038`.