error[E0106]: missing lifetime specifier --> $DIR/issue-26638.rs:1:62 | LL | fn parse_type(iter: Box+'static>) -> &str { iter.next() } | ------------------------------------ ^ expected named lifetime parameter | = help: this function's return type contains a borrowed value, but the signature does not say which one of `iter`'s 2 lifetimes it is borrowed from help: consider introducing a named lifetime parameter | LL | fn parse_type<'a>(iter: Box+'static>) -> &'a str { iter.next() } | ++++ ++ ++ error[E0106]: missing lifetime specifier --> $DIR/issue-26638.rs:5:40 | LL | fn parse_type_2(iter: fn(&u8)->&u8) -> &str { iter() } | ^ 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 | LL | fn parse_type_2(iter: fn(&u8)->&u8) -> &'static str { iter() } | +++++++ error[E0106]: missing lifetime specifier --> $DIR/issue-26638.rs:10:22 | LL | fn parse_type_3() -> &str { unimplemented!() } | ^ 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 | LL | fn parse_type_3() -> &'static str { unimplemented!() } | +++++++ error[E0308]: mismatched types --> $DIR/issue-26638.rs:1:69 | LL | fn parse_type(iter: Box+'static>) -> &str { iter.next() } | ---- ^^^^^^^^^^^ expected `&str`, found `Option<&str>` | | | expected `&str` because of return type | = note: expected reference `&str` found enum `Option<&str>` error[E0061]: this function takes 1 argument but 0 arguments were supplied --> $DIR/issue-26638.rs:5:47 | LL | fn parse_type_2(iter: fn(&u8)->&u8) -> &str { iter() } | ^^^^-- an argument of type `&u8` is missing | help: provide the argument | LL | fn parse_type_2(iter: fn(&u8)->&u8) -> &str { iter(/* &u8 */) } | ~~~~~~~~~~~ error[E0308]: mismatched types --> $DIR/issue-26638.rs:5:47 | LL | fn parse_type_2(iter: fn(&u8)->&u8) -> &str { iter() } | ---- ^^^^^^ expected `&str`, found `&u8` | | | expected `&'static str` because of return type | = note: expected reference `&'static str` found reference `&u8` error: aborting due to 6 previous errors Some errors have detailed explanations: E0061, E0106, E0308. For more information about an error, try `rustc --explain E0061`.