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