error[E0373]: closure may outlive the current function, but it borrows `prefix`, which is owned by the current function --> $DIR/does-not-live-long-enough.rs:6:33 | LL | self.data.iter().filter(|s| s.starts_with(prefix)).map(|s| s.as_ref()) | ^^^ ------ `prefix` is borrowed here | | | may outlive borrowed value `prefix` | note: closure is returned here --> $DIR/does-not-live-long-enough.rs:6:9 | LL | self.data.iter().filter(|s| s.starts_with(prefix)).map(|s| s.as_ref()) | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: to force the closure to take ownership of `prefix` (and any other referenced variables), use the `move` keyword | LL | self.data.iter().filter(move |s| s.starts_with(prefix)).map(|s| s.as_ref()) | ++++ error: aborting due to previous error For more information about this error, try `rustc --explain E0373`.