mirror of https://github.com/rust-lang/rust
33 lines
1.1 KiB
Rust
33 lines
1.1 KiB
Rust
// Issue #62007: assigning over a const-index projection of an array
|
|
// (in this case, `list[I] = n;`) should in theory be able to kill all borrows
|
|
// of `list[0]`, so that `list[0]` could be borrowed on the next
|
|
// iteration through the loop.
|
|
//
|
|
// Currently the compiler does not allow this. We may want to consider
|
|
// loosening that restriction in the future. (However, doing so would
|
|
// at *least* require T-lang team approval, and probably an RFC; e.g.
|
|
// such loosening might make complicate the user's mental mode; it
|
|
// also would make code more brittle in the face of refactorings that
|
|
// replace constants with variables.
|
|
|
|
#![allow(dead_code)]
|
|
|
|
struct List<T> {
|
|
value: T,
|
|
next: Option<Box<List<T>>>,
|
|
}
|
|
|
|
fn to_refs<T>(mut list: [&mut List<T>; 2]) -> Vec<&mut T> {
|
|
let mut result = vec![];
|
|
loop {
|
|
result.push(&mut list[0].value); //~ ERROR cannot borrow `list[_].value` as mutable
|
|
if let Some(n) = list[0].next.as_mut() { //~ ERROR cannot borrow `list[_].next` as mutable
|
|
list[0] = n;
|
|
} else {
|
|
return result;
|
|
}
|
|
}
|
|
}
|
|
|
|
fn main() {}
|