50 lines
1.3 KiB
Rust
50 lines
1.3 KiB
Rust
#![allow(dead_code)]
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// Compared to `assignment-kills-loans.rs`, we check here
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// that we do not kill too many borrows. Assignments to the `.1`
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// field projections should leave the borrows on `.0` intact.
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// compile-flags: -Z polonius
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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 assignment_to_field_projection<'a, T>(
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mut list: (&'a mut List<T>, &'a mut List<T>),
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) -> Vec<&'a 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);
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//~^ ERROR cannot borrow `list.0.value` as mutable
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if let Some(n) = (list.0).next.as_mut() {
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//~^ ERROR cannot borrow `list.0.next` as mutable
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list.1 = 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 assignment_through_projection_chain<'a, T>(
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mut list: (((((Box<&'a mut List<T>>, Box<&'a mut List<T>>),),),),),
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) -> Vec<&'a mut T> {
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let mut result = vec![];
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loop {
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result.push(&mut ((((list.0).0).0).0).0.value);
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//~^ ERROR cannot borrow `list.0.0.0.0.0.value` as mutable
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if let Some(n) = ((((list.0).0).0).0).0.next.as_mut() {
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//~^ ERROR cannot borrow `list.0.0.0.0.0.next` as mutable
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*((((list.0).0).0).0).1 = 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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