gistfile1.txt

fn vec_peek<T>(v: &'r [T]) -> Option< (&'r T, &'r [T]) > {
    if v.len() == 0 {
        None
    } else {
        let head = &v[0];
        let tail = v.view(1, v.len());
        Some( (head, tail) )
    }
}

/tmp/foo2.rs:6:19: 6:20 error: illegal borrow: borrowed value does not live long enough
/tmp/foo2.rs:6         let tail = v.view(1, v.len());
                                  ^
/tmp/foo2.rs:1:57: 9:1 note: borrowed pointer must be valid for the lifetime &'r  as defined on the block at 1:57...
/tmp/foo2.rs:1 fn vec_peek<T>(v: &'r [T]) -> Option< (&'r T, &'r [T]) > {
/tmp/foo2.rs:2     if v.len() == 0 {
/tmp/foo2.rs:3         None
/tmp/foo2.rs:4     } else {
/tmp/foo2.rs:5         let head = &v[0];
/tmp/foo2.rs:6         let tail = v.view(1, v.len());
               ...
/tmp/foo2.rs:1:0: 9:1 note: ...but borrowed value is only valid for the function body at 1:0
/tmp/foo2.rs:1 fn vec_peek<T>(v: &'r [T]) -> Option< (&'r T, &'r [T]) > {
/tmp/foo2.rs:2     if v.len() == 0 {
/tmp/foo2.rs:3         None
/tmp/foo2.rs:4     } else {
/tmp/foo2.rs:5         let head = &v[0];
/tmp/foo2.rs:6         let tail = v.view(1, v.len());
               ...
error: aborting due to previous error