Document how closure capturing interacts with discriminant reads #1837
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This is the behavior after the bugfixes in rustc PR 138961.
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| r[type.closure.capture.precision.discriminants] | ||
| ### Capturing for discriminant reads | ||
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| If pattern matching requires inspecting a discriminant, the relevant place will get captured by `ImmBorrow`. |
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Unless we mutably access the contents, right? E.g.
let c = || match x {
(Example::A(ref mut _y), _) => println!("variant A"),
(Example::B(_), _) => println!("variant B"),
};Is that already implied by the other rules?
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ok yep, that's the "Shared prefix" thing
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Yup. Do you think this deserves a clarification? (if so, how would you word it)
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no, I think it's clear in the context
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This is the behavior after the bugfixes in rust-lang/rust#138961. I have successfully ran
mdbook testwithRUSTUP_TOOLCHAINpointed at a stage1 built on top of the aforementioned PR – until it's merged, the CI here will fail.