38 lines
1.8 KiB
Plaintext
38 lines
1.8 KiB
Plaintext
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error: captured variable cannot escape `FnMut` closure body
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--> $DIR/issue-95079-missing-move-in-nested-closure.rs:3:29
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LL | fn foo1(s: &str) -> impl Iterator<Item = String> + '_ {
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| - variable defined here
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LL | None.into_iter()
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LL | .flat_map(move |()| s.chars().map(|c| format!("{}{}", c, s)))
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| - -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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| | |
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| | returns a reference to a captured variable which escapes the closure body
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| | variable captured here
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| inferred to be a `FnMut` closure
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= note: `FnMut` closures only have access to their captured variables while they are executing...
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= note: ...therefore, they cannot allow references to captured variables to escape
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help: consider adding 'move' keyword before the nested closure
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LL | .flat_map(move |()| s.chars().map(move |c| format!("{}{}", c, s)))
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| ++++
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error: lifetime may not live long enough
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--> $DIR/issue-95079-missing-move-in-nested-closure.rs:9:15
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LL | move |()| s.chars().map(|c| format!("{}{}", c, s))
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| --------- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'1` must outlive `'2`
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| | return type of closure `Map<Chars<'_>, [closure@$DIR/issue-95079-missing-move-in-nested-closure.rs:9:29: 9:32]>` contains a lifetime `'2`
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| lifetime `'1` represents this closure's body
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= note: closure implements `Fn`, so references to captured variables can't escape the closure
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help: consider adding 'move' keyword before the nested closure
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LL | move |()| s.chars().map(move |c| format!("{}{}", c, s))
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| ++++
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error: aborting due to 2 previous errors
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