error[E0261]: use of undeclared lifetime name `'short` --> $DIR/issue-107090.rs:4:9 | LL | Foo<'short, 'out, T>: Convert<'a, 'b>; | ^^^^^^ undeclared lifetime | = note: for more information on higher-ranked polymorphism, visit https://doc.rust-lang.org/nomicon/hrtb.html help: consider making the bound lifetime-generic with a new `'short` lifetime | LL | for<'short> Foo<'short, 'out, T>: Convert<'a, 'b>; | +++++++++++ help: consider introducing lifetime `'short` here | LL | struct Foo<'short, 'a, 'b, T>(PhantomData<(&'a (), &'b (), T)>) | +++++++ error[E0261]: use of undeclared lifetime name `'out` --> $DIR/issue-107090.rs:4:17 | LL | Foo<'short, 'out, T>: Convert<'a, 'b>; | ^^^^ undeclared lifetime | help: consider making the bound lifetime-generic with a new `'out` lifetime | LL | for<'out> Foo<'short, 'out, T>: Convert<'a, 'b>; | +++++++++ help: consider introducing lifetime `'out` here | LL | struct Foo<'out, 'a, 'b, T>(PhantomData<(&'a (), &'b (), T)>) | +++++ error[E0261]: use of undeclared lifetime name `'b` --> $DIR/issue-107090.rs:11:47 | LL | impl<'long: 'short, 'short, T> Convert<'long, 'b> for Foo<'short, 'out, T> { | - ^^ undeclared lifetime | | | help: consider introducing lifetime `'b` here: `'b,` error[E0261]: use of undeclared lifetime name `'out` --> $DIR/issue-107090.rs:11:67 | LL | impl<'long: 'short, 'short, T> Convert<'long, 'b> for Foo<'short, 'out, T> { | - help: consider introducing lifetime `'out` here: `'out,` ^^^^ undeclared lifetime error[E0261]: use of undeclared lifetime name `'out` --> $DIR/issue-107090.rs:14:49 | LL | fn cast(&'long self) -> &'short Foo<'short, 'out, T> { | ^^^^ undeclared lifetime | help: consider introducing lifetime `'out` here | LL | fn cast<'out>(&'long self) -> &'short Foo<'short, 'out, T> { | ++++++ help: consider introducing lifetime `'out` here | LL | impl<'out, 'long: 'short, 'short, T> Convert<'long, 'b> for Foo<'short, 'out, T> { | +++++ error[E0261]: use of undeclared lifetime name `'short` --> $DIR/issue-107090.rs:20:68 | LL | fn badboi<'in_, 'out, T>(x: Foo<'in_, 'out, T>, sadness: &'in_ Foo<'short, 'out, T>) -> &'out T { | - ^^^^^^ undeclared lifetime | | | help: consider introducing lifetime `'short` here: `'short,` error[E0308]: mismatched types --> $DIR/issue-107090.rs:22:5 | LL | fn badboi<'in_, 'out, T>(x: Foo<'in_, 'out, T>, sadness: &'in_ Foo<'short, 'out, T>) -> &'out T { | - this type parameter ------- expected `&'out T` because of return type LL | LL | sadness.cast() | ^^^^^^^^^^^^^^ expected `&T`, found `&Foo<'_, '_, T>` | = note: expected reference `&'out T` found reference `&Foo<'_, '_, T>` error: aborting due to 7 previous errors Some errors have detailed explanations: E0261, E0308. For more information about an error, try `rustc --explain E0261`.