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// FIXME: the following cases need to suggest more things to make users reach a working end state.
mod bav {
trait OtherTrait<'a> {}
impl<'a> OtherTrait<'a> for &'a () {}
trait ObjectTrait {
type Assoc: Bar;
}
trait MyTrait {
fn use_self(&self) -> &() { panic!() }
}
trait Bar {}
impl MyTrait for Box<dyn ObjectTrait<Assoc = i32>> {
fn use_self(&self) -> &() { panic!() }
}
impl Bar for i32 {}
fn use_it<'a>(val: Box<dyn ObjectTrait<Assoc = i32>>) -> impl OtherTrait<'a> {
val.use_self() //~ ERROR cannot return reference to function parameter
}
}
mod bap {
trait OtherTrait<'a> {}
impl<'a> OtherTrait<'a> for &'a () {}
trait ObjectTrait {
type Assoc: Bar;
}
trait MyTrait {
fn use_self(&self) -> &() { panic!() }
}
trait Bar {}
impl MyTrait for Box<dyn ObjectTrait<Assoc = i32>> {
fn use_self(&self) -> &() { panic!() }
}
impl Bar for i32 {}
fn use_it<'a>(val: Box<dyn ObjectTrait<Assoc = i32>>) -> impl OtherTrait<'a> + 'a {
val.use_self() //~ ERROR E0515
}
}
// This case in particular requires the user to write all of the bounds we have in `mod bax`.
mod bay {
trait OtherTrait<'a> {}
impl<'a> OtherTrait<'a> for &'a () {}
trait ObjectTrait {
type Assoc: Bar;
}
trait MyTrait {
fn use_self(&self) -> &() { panic!() }
}
trait Bar {}
impl MyTrait for Box<dyn ObjectTrait<Assoc = i32>> {
fn use_self(&self) -> &() { panic!() }
}
impl Bar for i32 {}
fn use_it<'a>(val: Box<dyn ObjectTrait<Assoc = i32> + 'a>) -> &'a () {
val.use_self()
}
}
mod bax {
trait OtherTrait<'a> {}
impl<'a> OtherTrait<'a> for &'a () {}
trait ObjectTrait {
type Assoc: Bar;
}
trait MyTrait<'a> {
fn use_self(&'a self) -> &'a () { panic!() }
}
trait Bar {}
impl<'a> MyTrait<'a> for Box<dyn ObjectTrait<Assoc = i32> + 'a> {
fn use_self(&'a self) -> &'a () { panic!() }
}
impl Bar for i32 {}
fn use_it<'a>(val: Box<dyn ObjectTrait<Assoc = i32> + 'a>) -> &'a () {
val.use_self()
}
}
mod baw {
trait OtherTrait<'a> {}
impl<'a> OtherTrait<'a> for &'a () {}
trait ObjectTrait {
type Assoc: Bar;
}
trait MyTrait {
fn use_self(&self) -> &() { panic!() }
}
trait Bar {}
impl<'a> MyTrait for Box<dyn ObjectTrait<Assoc = Box<dyn Bar>>> {
fn use_self(&self) -> &() { panic!() }
}
fn use_it<'a>(val: Box<dyn ObjectTrait<Assoc = Box<dyn Bar>>>) -> impl OtherTrait<'a> + 'a{
val.use_self() //~ ERROR E0515
}
}
fn main() {}
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