From 102997a9391cb4c4eac6cddf5e8fdf1aa369ea69 Mon Sep 17 00:00:00 2001 From: Veera Date: Sat, 13 Jul 2024 11:49:14 -0400 Subject: [PATCH] Update Tests --- .../dyn-keyword/dyn-2021-edition-error.stderr | 10 +- ...t-in-fn-inputs-and-outputs-issue-125139.rs | 142 ++++ ...-fn-inputs-and-outputs-issue-125139.stderr | 673 ++++++++++++++++++ 3 files changed, 824 insertions(+), 1 deletion(-) create mode 100644 tests/ui/object-safety/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs create mode 100644 tests/ui/object-safety/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.stderr diff --git a/tests/ui/dyn-keyword/dyn-2021-edition-error.stderr b/tests/ui/dyn-keyword/dyn-2021-edition-error.stderr index b39689afd1ca6..52ee6c81ab794 100644 --- a/tests/ui/dyn-keyword/dyn-2021-edition-error.stderr +++ b/tests/ui/dyn-keyword/dyn-2021-edition-error.stderr @@ -4,7 +4,15 @@ error[E0782]: trait objects must include the `dyn` keyword LL | fn function(x: &SomeTrait, y: Box) { | ^^^^^^^^^ | -help: add `dyn` keyword before this trait +help: use a new generic type parameter, constrained by `SomeTrait` + | +LL | fn function(x: &T, y: Box) { + | ++++++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn function(x: &impl SomeTrait, y: Box) { + | ++++ +help: alternatively, use a trait object to accept any type that implements `SomeTrait`, accessing its methods at runtime using dynamic dispatch | LL | fn function(x: &dyn SomeTrait, y: Box) { | +++ diff --git a/tests/ui/object-safety/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs b/tests/ui/object-safety/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs new file mode 100644 index 0000000000000..dceb6e0fe710d --- /dev/null +++ b/tests/ui/object-safety/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs @@ -0,0 +1,142 @@ +//@ edition:2021 + +trait Trait {} + +struct IceCream; + +impl IceCream { + fn foo(_: &Trait) {} + //~^ ERROR: trait objects must include the `dyn` keyword + + fn bar(self, _: &'a Trait) {} + //~^ ERROR: trait objects must include the `dyn` keyword + //~| ERROR: use of undeclared lifetime name + + fn alice<'a>(&self, _: &Trait) {} + //~^ ERROR: trait objects must include the `dyn` keyword + + fn bob<'a>(_: &'a Trait) {} + //~^ ERROR: trait objects must include the `dyn` keyword + + fn cat() -> &Trait { + //~^ ERROR: missing lifetime specifier + //~| ERROR: trait objects must include the `dyn` keyword + &Type + } + + fn dog<'a>() -> &Trait { + //~^ ERROR: missing lifetime specifier + //~| ERROR: trait objects must include the `dyn` keyword + &Type + } + + fn kitten() -> &'a Trait { + //~^ ERROR: use of undeclared lifetime name + //~| ERROR: trait objects must include the `dyn` keyword + &Type + } + + fn puppy<'a>() -> &'a Trait { + //~^ ERROR: trait objects must include the `dyn` keyword + &Type + } + + fn parrot() -> &mut Trait { + //~^ ERROR: missing lifetime specifier + //~| ERROR: cannot return a mutable reference to a bare trait + &mut Type + //~^ ERROR: cannot return reference to temporary value + } +} + +trait Sing { + fn foo(_: &Trait); + //~^ ERROR: trait objects must include the `dyn` keyword + + fn bar(_: &'a Trait); + //~^ ERROR: trait objects must include the `dyn` keyword + //~| ERROR: use of undeclared lifetime name + + fn alice<'a>(_: &Trait); + //~^ ERROR: trait objects must include the `dyn` keyword + + fn bob<'a>(_: &'a Trait); + //~^ ERROR: trait objects must include the `dyn` keyword + + fn cat() -> &Trait; + //~^ ERROR: missing lifetime specifier + //~| ERROR: trait objects must include the `dyn` keyword + + fn dog<'a>() -> &Trait { + //~^ ERROR: missing lifetime specifier + //~| ERROR: trait objects must include the `dyn` keyword + &Type + } + + fn kitten() -> &'a Trait { + //~^ ERROR: use of undeclared lifetime name + //~| ERROR: trait objects must include the `dyn` keyword + &Type + } + + fn puppy<'a>() -> &'a Trait { + //~^ ERROR: trait objects must include the `dyn` keyword + &Type + } + + fn parrot() -> &mut Trait { + //~^ ERROR: missing lifetime specifier + //~| ERROR: cannot return a mutable reference to a bare trait + &mut Type + //~^ ERROR: cannot return reference to temporary value + } +} + +fn foo(_: &Trait) {} +//~^ ERROR: trait objects must include the `dyn` keyword + +fn bar(_: &'a Trait) {} +//~^ ERROR: trait objects must include the `dyn` keyword +//~| ERROR: use of undeclared lifetime name + +fn alice<'a>(_: &Trait) {} +//~^ ERROR: trait objects must include the `dyn` keyword + +fn bob<'a>(_: &'a Trait) {} +//~^ ERROR: trait objects must include the `dyn` keyword + +struct Type; + +impl Trait for Type {} + +fn cat() -> &Trait { +//~^ ERROR: missing lifetime specifier +//~| ERROR: trait objects must include the `dyn` keyword + &Type +} + +fn dog<'a>() -> &Trait { +//~^ ERROR: missing lifetime specifier +//~| ERROR: trait objects must include the `dyn` keyword + &Type +} + +fn kitten() -> &'a Trait { +//~^ ERROR: use of undeclared lifetime name +//~| ERROR: trait objects must include the `dyn` keyword + &Type +} + +fn puppy<'a>() -> &'a Trait { +//~^ ERROR: trait objects must include the `dyn` keyword + &Type +} + +fn parrot() -> &mut Trait { + //~^ ERROR: missing lifetime specifier + //~| ERROR: cannot return a mutable reference to a bare trait + &mut Type + //~^ ERROR: cannot return reference to temporary value +} + +fn main() {} diff --git a/tests/ui/object-safety/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.stderr b/tests/ui/object-safety/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.stderr new file mode 100644 index 0000000000000..15c8eb5d16c2c --- /dev/null +++ b/tests/ui/object-safety/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.stderr @@ -0,0 +1,673 @@ +error[E0261]: use of undeclared lifetime name `'a` + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:11:22 + | +LL | fn bar(self, _: &'a Trait) {} + | ^^ undeclared lifetime + | +help: consider introducing lifetime `'a` here + | +LL | fn bar<'a>(self, _: &'a Trait) {} + | ++++ +help: consider introducing lifetime `'a` here + | +LL | impl<'a> IceCream { + | ++++ + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:21:17 + | +LL | fn cat() -> &Trait { + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static` + | +LL | fn cat() -> &'static Trait { + | +++++++ + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:27:21 + | +LL | fn dog<'a>() -> &Trait { + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'a` lifetime + | +LL | fn dog<'a>() -> &'a Trait { + | ++ + +error[E0261]: use of undeclared lifetime name `'a` + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:33:21 + | +LL | fn kitten() -> &'a Trait { + | ^^ undeclared lifetime + | +help: consider introducing lifetime `'a` here + | +LL | fn kitten<'a>() -> &'a Trait { + | ++++ +help: consider introducing lifetime `'a` here + | +LL | impl<'a> IceCream { + | ++++ + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:44:20 + | +LL | fn parrot() -> &mut Trait { + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static` + | +LL | fn parrot() -> &'static mut Trait { + | +++++++ + +error[E0261]: use of undeclared lifetime name `'a` + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:56:16 + | +LL | fn bar(_: &'a Trait); + | ^^ undeclared lifetime + | +help: consider introducing lifetime `'a` here + | +LL | fn bar<'a>(_: &'a Trait); + | ++++ +help: consider introducing lifetime `'a` here + | +LL | trait Sing<'a> { + | ++++ + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:66:17 + | +LL | fn cat() -> &Trait; + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static` + | +LL | fn cat() -> &'static Trait; + | +++++++ +help: instead, you are more likely to want to return an owned value + | +LL - fn cat() -> &Trait; +LL + fn cat() -> Trait; + | + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:70:21 + | +LL | fn dog<'a>() -> &Trait { + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'a` lifetime + | +LL | fn dog<'a>() -> &'a Trait { + | ++ + +error[E0261]: use of undeclared lifetime name `'a` + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:76:21 + | +LL | fn kitten() -> &'a Trait { + | ^^ undeclared lifetime + | +help: consider introducing lifetime `'a` here + | +LL | fn kitten<'a>() -> &'a Trait { + | ++++ +help: consider introducing lifetime `'a` here + | +LL | trait Sing<'a> { + | ++++ + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:87:20 + | +LL | fn parrot() -> &mut Trait { + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static` + | +LL | fn parrot() -> &'static mut Trait { + | +++++++ + +error[E0261]: use of undeclared lifetime name `'a` + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:98:12 + | +LL | fn bar(_: &'a Trait) {} + | - ^^ undeclared lifetime + | | + | help: consider introducing lifetime `'a` here: `<'a>` + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:112:13 + | +LL | fn cat() -> &Trait { + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static` + | +LL | fn cat() -> &'static Trait { + | +++++++ + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:118:17 + | +LL | fn dog<'a>() -> &Trait { + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'a` lifetime + | +LL | fn dog<'a>() -> &'a Trait { + | ++ + +error[E0261]: use of undeclared lifetime name `'a` + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:124:17 + | +LL | fn kitten() -> &'a Trait { + | - ^^ undeclared lifetime + | | + | help: consider introducing lifetime `'a` here: `<'a>` + +error[E0106]: missing lifetime specifier + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:135:16 + | +LL | fn parrot() -> &mut Trait { + | ^ expected named lifetime parameter + | + = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from +help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static` + | +LL | fn parrot() -> &'static mut Trait { + | +++++++ + +error[E0515]: cannot return reference to temporary value + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:47:9 + | +LL | &mut Type + | ^^^^^---- + | | | + | | temporary value created here + | returns a reference to data owned by the current function + +error[E0515]: cannot return reference to temporary value + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:90:9 + | +LL | &mut Type + | ^^^^^---- + | | | + | | temporary value created here + | returns a reference to data owned by the current function + +error[E0515]: cannot return reference to temporary value + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:138:5 + | +LL | &mut Type + | ^^^^^---- + | | | + | | temporary value created here + | returns a reference to data owned by the current function + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:53:16 + | +LL | fn foo(_: &Trait); + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn foo(_: &T); + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn foo(_: &impl Trait); + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn foo(_: &dyn Trait); + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:56:19 + | +LL | fn bar(_: &'a Trait); + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn bar(_: &'a T); + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn bar(_: &'a impl Trait); + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn bar(_: &'a dyn Trait); + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:60:22 + | +LL | fn alice<'a>(_: &Trait); + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn alice<'a, T: Trait>(_: &T); + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn alice<'a>(_: &impl Trait); + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn alice<'a>(_: &dyn Trait); + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:63:23 + | +LL | fn bob<'a>(_: &'a Trait); + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn bob<'a, T: Trait>(_: &'a T); + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn bob<'a>(_: &'a impl Trait); + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn bob<'a>(_: &'a dyn Trait); + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:66:18 + | +LL | fn cat() -> &Trait; + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn cat<'a>() -> &'a impl Trait; + | ++++ +++++++ +help: alternatively, you can return an owned trait object + | +LL | fn cat() -> Box; + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:70:22 + | +LL | fn dog<'a>() -> &Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn dog<'b, 'a>() -> &'b impl Trait { + | +++ +++++++ +help: alternatively, you can return an owned trait object + | +LL | fn dog<'a>() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:76:24 + | +LL | fn kitten() -> &'a Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn kitten() -> &'a impl Trait { + | ++++ +help: alternatively, you can return an owned trait object + | +LL | fn kitten() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:82:27 + | +LL | fn puppy<'a>() -> &'a Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn puppy<'a>() -> &'a impl Trait { + | ++++ +help: alternatively, you can return an owned trait object + | +LL | fn puppy<'a>() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: cannot return a mutable reference to a bare trait + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:87:25 + | +LL | fn parrot() -> &mut Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn parrot() -> impl Trait { + | ~~~~~~~~~~ +help: alternatively, you can return an owned trait object + | +LL | fn parrot() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:95:12 + | +LL | fn foo(_: &Trait) {} + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn foo(_: &T) {} + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn foo(_: &impl Trait) {} + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn foo(_: &dyn Trait) {} + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:98:15 + | +LL | fn bar(_: &'a Trait) {} + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn bar(_: &'a T) {} + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn bar(_: &'a impl Trait) {} + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn bar(_: &'a dyn Trait) {} + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:102:18 + | +LL | fn alice<'a>(_: &Trait) {} + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn alice<'a, T: Trait>(_: &T) {} + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn alice<'a>(_: &impl Trait) {} + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn alice<'a>(_: &dyn Trait) {} + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:105:19 + | +LL | fn bob<'a>(_: &'a Trait) {} + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn bob<'a, T: Trait>(_: &'a T) {} + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn bob<'a>(_: &'a impl Trait) {} + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn bob<'a>(_: &'a dyn Trait) {} + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:112:14 + | +LL | fn cat() -> &Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn cat<'a>() -> &'a impl Trait { + | ++++ +++++++ +help: alternatively, you can return an owned trait object + | +LL | fn cat() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:118:18 + | +LL | fn dog<'a>() -> &Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn dog<'b, 'a>() -> &'b impl Trait { + | +++ +++++++ +help: alternatively, you can return an owned trait object + | +LL | fn dog<'a>() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:124:20 + | +LL | fn kitten() -> &'a Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn kitten() -> &'a impl Trait { + | ++++ +help: alternatively, you can return an owned trait object + | +LL | fn kitten() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:130:23 + | +LL | fn puppy<'a>() -> &'a Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn puppy<'a>() -> &'a impl Trait { + | ++++ +help: alternatively, you can return an owned trait object + | +LL | fn puppy<'a>() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: cannot return a mutable reference to a bare trait + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:135:21 + | +LL | fn parrot() -> &mut Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn parrot() -> impl Trait { + | ~~~~~~~~~~ +help: alternatively, you can return an owned trait object + | +LL | fn parrot() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:8:16 + | +LL | fn foo(_: &Trait) {} + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn foo(_: &T) {} + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn foo(_: &impl Trait) {} + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn foo(_: &dyn Trait) {} + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:11:25 + | +LL | fn bar(self, _: &'a Trait) {} + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn bar(self, _: &'a T) {} + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn bar(self, _: &'a impl Trait) {} + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn bar(self, _: &'a dyn Trait) {} + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:15:29 + | +LL | fn alice<'a>(&self, _: &Trait) {} + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn alice<'a, T: Trait>(&self, _: &T) {} + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn alice<'a>(&self, _: &impl Trait) {} + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn alice<'a>(&self, _: &dyn Trait) {} + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:18:23 + | +LL | fn bob<'a>(_: &'a Trait) {} + | ^^^^^ + | +help: use a new generic type parameter, constrained by `Trait` + | +LL | fn bob<'a, T: Trait>(_: &'a T) {} + | ++++++++++ ~ +help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference + | +LL | fn bob<'a>(_: &'a impl Trait) {} + | ++++ +help: alternatively, use a trait object to accept any type that implements `Trait`, accessing its methods at runtime using dynamic dispatch + | +LL | fn bob<'a>(_: &'a dyn Trait) {} + | +++ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:21:18 + | +LL | fn cat() -> &Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn cat<'a>() -> &'a impl Trait { + | ++++ +++++++ +help: alternatively, you can return an owned trait object + | +LL | fn cat() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:27:22 + | +LL | fn dog<'a>() -> &Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn dog<'b, 'a>() -> &'b impl Trait { + | +++ +++++++ +help: alternatively, you can return an owned trait object + | +LL | fn dog<'a>() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:33:24 + | +LL | fn kitten() -> &'a Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn kitten() -> &'a impl Trait { + | ++++ +help: alternatively, you can return an owned trait object + | +LL | fn kitten() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: trait objects must include the `dyn` keyword + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:39:27 + | +LL | fn puppy<'a>() -> &'a Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn puppy<'a>() -> &'a impl Trait { + | ++++ +help: alternatively, you can return an owned trait object + | +LL | fn puppy<'a>() -> Box { + | ~~~~~~~~~~~~~~ + +error[E0782]: cannot return a mutable reference to a bare trait + --> $DIR/reference-to-bare-trait-in-fn-inputs-and-outputs-issue-125139.rs:44:25 + | +LL | fn parrot() -> &mut Trait { + | ^^^^^ + | +help: use `impl Trait` to return an opaque type, as long as you return a single underlying type + | +LL | fn parrot() -> impl Trait { + | ~~~~~~~~~~ +help: alternatively, you can return an owned trait object + | +LL | fn parrot() -> Box { + | ~~~~~~~~~~~~~~ + +error: aborting due to 45 previous errors + +Some errors have detailed explanations: E0106, E0261, E0515, E0782. +For more information about an error, try `rustc --explain E0106`.