error[E0261]: use of undeclared lifetime name `'b` --> $DIR/generic_associated_type_undeclared_lifetimes.rs:9:37 | LL | + Deref>; | ^^ undeclared lifetime | = help: if you want to experiment with in-band lifetime bindings, add `#![feature(in_band_lifetimes)]` to the crate attributes help: consider introducing lifetime `'b` here | LL | trait Iterable<'b> { | ^^^^ help: consider introducing lifetime `'b` here | LL | type Iter<'b, 'a>: Iterator> | ^^^ error[E0261]: use of undeclared lifetime name `'undeclared` --> $DIR/generic_associated_type_undeclared_lifetimes.rs:12:41 | LL | fn iter<'a>(&'a self) -> Self::Iter<'undeclared>; | ^^^^^^^^^^^ undeclared lifetime | = help: if you want to experiment with in-band lifetime bindings, add `#![feature(in_band_lifetimes)]` to the crate attributes help: consider introducing lifetime `'undeclared` here | LL | trait Iterable<'undeclared> { | ^^^^^^^^^^^^^ help: consider introducing lifetime `'undeclared` here | LL | fn iter<'undeclared, 'a>(&'a self) -> Self::Iter<'undeclared>; | ^^^^^^^^^^^^ error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0261`.