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|
error[E0666]: nested `impl Trait` is not allowed
--> $DIR/where-allowed.rs:50:51
|
LL | fn in_impl_Fn_parameter_in_parameters(_: &impl Fn(impl Debug)) { panic!() }
| --------^^^^^^^^^^-
| | |
| | nested `impl Trait` here
| outer `impl Trait`
error[E0666]: nested `impl Trait` is not allowed
--> $DIR/where-allowed.rs:59:57
|
LL | fn in_impl_Fn_parameter_in_return() -> &'static impl Fn(impl Debug) { panic!() }
| --------^^^^^^^^^^-
| | |
| | nested `impl Trait` here
| outer `impl Trait`
error[E0658]: `impl Trait` in associated types is unstable
--> $DIR/where-allowed.rs:121:16
|
LL | type Out = impl Debug;
| ^^^^^^^^^^
|
= note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
= help: add `#![feature(impl_trait_in_assoc_type)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error[E0658]: `impl Trait` in type aliases is unstable
--> $DIR/where-allowed.rs:158:23
|
LL | type InTypeAlias<R> = impl Debug;
| ^^^^^^^^^^
|
= note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
= help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error[E0658]: `impl Trait` in type aliases is unstable
--> $DIR/where-allowed.rs:161:39
|
LL | type InReturnInTypeAlias<R> = fn() -> impl Debug;
| ^^^^^^^^^^
|
= note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
= help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error[E0562]: `impl Trait` is not allowed in `fn` pointer parameters
--> $DIR/where-allowed.rs:18:40
|
LL | fn in_fn_parameter_in_parameters(_: fn(impl Debug)) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in `fn` pointer return types
--> $DIR/where-allowed.rs:22:42
|
LL | fn in_fn_return_in_parameters(_: fn() -> impl Debug) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in `fn` pointer parameters
--> $DIR/where-allowed.rs:26:38
|
LL | fn in_fn_parameter_in_return() -> fn(impl Debug) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in `fn` pointer return types
--> $DIR/where-allowed.rs:30:40
|
LL | fn in_fn_return_in_return() -> fn() -> impl Debug { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the parameters of `Fn` trait bounds
--> $DIR/where-allowed.rs:34:49
|
LL | fn in_dyn_Fn_parameter_in_parameters(_: &dyn Fn(impl Debug)) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the return type of `Fn` trait bounds
--> $DIR/where-allowed.rs:38:51
|
LL | fn in_dyn_Fn_return_in_parameters(_: &dyn Fn() -> impl Debug) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the parameters of `Fn` trait bounds
--> $DIR/where-allowed.rs:42:55
|
LL | fn in_dyn_Fn_parameter_in_return() -> &'static dyn Fn(impl Debug) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the parameters of `Fn` trait bounds
--> $DIR/where-allowed.rs:50:51
|
LL | fn in_impl_Fn_parameter_in_parameters(_: &impl Fn(impl Debug)) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the return type of `Fn` trait bounds
--> $DIR/where-allowed.rs:55:53
|
LL | fn in_impl_Fn_return_in_parameters(_: &impl Fn() -> impl Debug) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the parameters of `Fn` trait bounds
--> $DIR/where-allowed.rs:59:57
|
LL | fn in_impl_Fn_parameter_in_return() -> &'static impl Fn(impl Debug) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the parameters of `Fn` trait bounds
--> $DIR/where-allowed.rs:68:38
|
LL | fn in_Fn_parameter_in_generics<F: Fn(impl Debug)> (_: F) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the return type of `Fn` trait bounds
--> $DIR/where-allowed.rs:72:40
|
LL | fn in_Fn_return_in_generics<F: Fn() -> impl Debug> (_: F) { panic!() }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in field types
--> $DIR/where-allowed.rs:85:32
|
LL | struct InBraceStructField { x: impl Debug }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in field types
--> $DIR/where-allowed.rs:89:41
|
LL | struct InAdtInBraceStructField { x: Vec<impl Debug> }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in field types
--> $DIR/where-allowed.rs:93:27
|
LL | struct InTupleStructField(impl Debug);
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in field types
--> $DIR/where-allowed.rs:98:25
|
LL | InBraceVariant { x: impl Debug },
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in field types
--> $DIR/where-allowed.rs:100:20
|
LL | InTupleVariant(impl Debug),
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in `extern fn` parameters
--> $DIR/where-allowed.rs:142:33
|
LL | fn in_foreign_parameters(_: impl Debug);
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in `extern fn` return types
--> $DIR/where-allowed.rs:145:31
|
LL | fn in_foreign_return() -> impl Debug;
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in `fn` pointer return types
--> $DIR/where-allowed.rs:161:39
|
LL | type InReturnInTypeAlias<R> = fn() -> impl Debug;
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in traits
--> $DIR/where-allowed.rs:166:16
|
LL | impl PartialEq<impl Debug> for () {
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in impl headers
--> $DIR/where-allowed.rs:171:24
|
LL | impl PartialEq<()> for impl Debug {
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in impl headers
--> $DIR/where-allowed.rs:176:6
|
LL | impl impl Debug {
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in impl headers
--> $DIR/where-allowed.rs:182:24
|
LL | impl InInherentImplAdt<impl Debug> {
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in bounds
--> $DIR/where-allowed.rs:188:11
|
LL | where impl Debug: Debug
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in bounds
--> $DIR/where-allowed.rs:195:15
|
LL | where Vec<impl Debug>: Debug
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in bounds
--> $DIR/where-allowed.rs:202:24
|
LL | where T: PartialEq<impl Debug>
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the parameters of `Fn` trait bounds
--> $DIR/where-allowed.rs:209:17
|
LL | where T: Fn(impl Debug)
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the return type of `Fn` trait bounds
--> $DIR/where-allowed.rs:216:22
|
LL | where T: Fn() -> impl Debug
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in generic parameter defaults
--> $DIR/where-allowed.rs:222:40
|
LL | struct InStructGenericParamDefault<T = impl Debug>(T);
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in generic parameter defaults
--> $DIR/where-allowed.rs:226:36
|
LL | enum InEnumGenericParamDefault<T = impl Debug> { Variant(T) }
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in generic parameter defaults
--> $DIR/where-allowed.rs:230:38
|
LL | trait InTraitGenericParamDefault<T = impl Debug> {}
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in generic parameter defaults
--> $DIR/where-allowed.rs:234:41
|
LL | type InTypeAliasGenericParamDefault<T = impl Debug> = T;
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in generic parameter defaults
--> $DIR/where-allowed.rs:238:11
|
LL | impl <T = impl Debug> T {}
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in generic parameter defaults
--> $DIR/where-allowed.rs:245:40
|
LL | fn in_method_generic_param_default<T = impl Debug>(_: T) {}
| ^^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0562]: `impl Trait` is not allowed in the type of variable bindings
--> $DIR/where-allowed.rs:251:29
|
LL | let _in_local_variable: impl Fn() = || {};
| ^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
= note: see issue #63065 <https://github.com/rust-lang/rust/issues/63065> for more information
= help: add `#![feature(impl_trait_in_bindings)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error[E0562]: `impl Trait` is not allowed in closure return types
--> $DIR/where-allowed.rs:253:46
|
LL | let _in_return_in_local_variable = || -> impl Fn() { || {} };
| ^^^^^^^^^
|
= note: `impl Trait` is only allowed in arguments and return types of functions and methods
error[E0053]: method `in_trait_impl_return` has an incompatible type for trait
--> $DIR/where-allowed.rs:128:34
|
LL | type Out = impl Debug;
| ---------- the expected opaque type
...
LL | fn in_trait_impl_return() -> impl Debug { () }
| ^^^^^^^^^^ expected opaque type, found a different opaque type
|
note: type in trait
--> $DIR/where-allowed.rs:118:34
|
LL | fn in_trait_impl_return() -> Self::Out;
| ^^^^^^^^^
= note: expected signature `fn() -> <() as DummyTrait>::Out`
found signature `fn() -> impl Debug`
= note: distinct uses of `impl Trait` result in different opaque types
help: change the output type to match the trait
|
LL | fn in_trait_impl_return() -> <() as DummyTrait>::Out { () }
| ~~~~~~~~~~~~~~~~~~~~~~~
error: defaults for type parameters are only allowed in `struct`, `enum`, `type`, or `trait` definitions
--> $DIR/where-allowed.rs:245:36
|
LL | fn in_method_generic_param_default<T = impl Debug>(_: T) {}
| ^^^^^^^^^^^^^^
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #36887 <https://github.com/rust-lang/rust/issues/36887>
= note: `#[deny(invalid_type_param_default)]` on by default
error: defaults for type parameters are only allowed in `struct`, `enum`, `type`, or `trait` definitions
--> $DIR/where-allowed.rs:238:7
|
LL | impl <T = impl Debug> T {}
| ^^^^^^^^^^^^^^
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #36887 <https://github.com/rust-lang/rust/issues/36887>
error[E0283]: type annotations needed
--> $DIR/where-allowed.rs:46:57
|
LL | fn in_dyn_Fn_return_in_return() -> &'static dyn Fn() -> impl Debug { panic!() }
| ^^^^^^^^^^ cannot infer type
|
= note: cannot satisfy `_: Debug`
error[E0283]: type annotations needed
--> $DIR/where-allowed.rs:64:46
|
LL | fn in_impl_Fn_return_in_return() -> &'static impl Fn() -> impl Debug { panic!() }
| ^^^^^^^^^^^^^^^^^^^^^^^ cannot infer type
|
= note: multiple `impl`s satisfying `_: Fn()` found in the following crates: `alloc`, `core`:
- impl<A, F> Fn<A> for &F
where A: Tuple, F: Fn<A>, F: ?Sized;
- impl<Args, F, A> Fn<Args> for Box<F, A>
where Args: Tuple, F: Fn<Args>, A: Allocator, F: ?Sized;
error[E0118]: no nominal type found for inherent implementation
--> $DIR/where-allowed.rs:238:1
|
LL | impl <T = impl Debug> T {}
| ^^^^^^^^^^^^^^^^^^^^^^^ impl requires a nominal type
|
= note: either implement a trait on it or create a newtype to wrap it instead
error: unconstrained opaque type
--> $DIR/where-allowed.rs:121:16
|
LL | type Out = impl Debug;
| ^^^^^^^^^^
|
= note: `Out` must be used in combination with a concrete type within the same impl
error: aborting due to 49 previous errors
Some errors have detailed explanations: E0053, E0118, E0283, E0562, E0658, E0666.
For more information about an error, try `rustc --explain E0053`.
Future incompatibility report: Future breakage diagnostic:
error: defaults for type parameters are only allowed in `struct`, `enum`, `type`, or `trait` definitions
--> $DIR/where-allowed.rs:245:36
|
LL | fn in_method_generic_param_default<T = impl Debug>(_: T) {}
| ^^^^^^^^^^^^^^
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #36887 <https://github.com/rust-lang/rust/issues/36887>
= note: `#[deny(invalid_type_param_default)]` on by default
Future breakage diagnostic:
error: defaults for type parameters are only allowed in `struct`, `enum`, `type`, or `trait` definitions
--> $DIR/where-allowed.rs:238:7
|
LL | impl <T = impl Debug> T {}
| ^^^^^^^^^^^^^^
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #36887 <https://github.com/rust-lang/rust/issues/36887>
= note: `#[deny(invalid_type_param_default)]` on by default
|
