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Diffstat (limited to '')
-rw-r--r-- | src/test/ui/error-codes/E0033-teach.stderr | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/src/test/ui/error-codes/E0033-teach.stderr b/src/test/ui/error-codes/E0033-teach.stderr new file mode 100644 index 000000000..3b68abbb4 --- /dev/null +++ b/src/test/ui/error-codes/E0033-teach.stderr @@ -0,0 +1,42 @@ +error[E0423]: expected value, found trait `SomeTrait` + --> $DIR/E0033-teach.rs:8:37 + | +LL | let trait_obj: &dyn SomeTrait = SomeTrait; + | ^^^^^^^^^ not a value + +error[E0038]: the trait `SomeTrait` cannot be made into an object + --> $DIR/E0033-teach.rs:8:20 + | +LL | let trait_obj: &dyn SomeTrait = SomeTrait; + | ^^^^^^^^^^^^^^ `SomeTrait` 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/E0033-teach.rs:4:8 + | +LL | trait SomeTrait { + | --------- this trait cannot be made into an object... +LL | fn foo(); + | ^^^ ...because associated function `foo` has no `self` parameter +help: consider turning `foo` into a method by giving it a `&self` argument + | +LL | fn foo(&self); + | +++++ +help: alternatively, consider constraining `foo` so it does not apply to trait objects + | +LL | fn foo() where Self: Sized; + | +++++++++++++++++ + +error[E0033]: type `&dyn SomeTrait` cannot be dereferenced + --> $DIR/E0033-teach.rs:12:9 + | +LL | let &invalid = trait_obj; + | ^^^^^^^^ type `&dyn SomeTrait` cannot be dereferenced + | + = note: This error indicates that a pointer to a trait type cannot be implicitly dereferenced by a pattern. Every trait defines a type, but because the size of trait implementors isn't fixed, this type has no compile-time size. Therefore, all accesses to trait types must be through pointers. If you encounter this error you should try to avoid dereferencing the pointer. + + You can read more about trait objects in the Trait Objects section of the Reference: https://doc.rust-lang.org/reference/types.html#trait-objects + +error: aborting due to 3 previous errors + +Some errors have detailed explanations: E0033, E0038, E0423. +For more information about an error, try `rustc --explain E0033`. |