Cannot return value that references local variable
Local variables, function parameters and temporaries are all dropped before the end of the function body. So a reference to them cannot be returned.
Erroneous code example:
fn get_dangling_reference() -> &'static i32 { let x = 0; &x }
use std::slice::Iter; fn get_dangling_iterator<'a>() -> Iter<'a, i32> { let v = vec![1, 2, 3]; v.iter() }
Consider returning an owned value instead:
use std::vec::IntoIter; fn get_integer() -> i32 { let x = 0; x } fn get_owned_iterator() -> IntoIter<i32> { let v = vec![1, 2, 3]; v.into_iter() }