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Variable inaccessible after closure use in Rust

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What it should do

Process data using a closure and return processed results. Example: process_closure_capture(data) -> Vec<i32>

What happens instead

error[E0382]: borrow of moved value: `data`

fn process_closure_capture(data: Vec<i32>) -> Vec<i32> {
    let closure = |x| x + 1;
    let processed = data.into_iter().map(closure).collect::<Vec<i32>>();
    // Attempt to use `data` here
    data
}

fn main() {
    let data = vec![1, 2, 3];
    let result = process_closure_capture(data);
    println!("{:?}", result);
}

Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).

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This bug belongs to the scope and closure bugs pattern

Every callback reports the last value, a counter never increments, UnboundLocalError on a variable you can see.

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fn process_closure_capture(data: Vec<i32>) -> Vec<i32> { let closure = |x| x + 1; let processed = data.into_iter().map(closure).collect::<Vec<i32>>(); // Attempt to use `data` here data } fn main() { let data = vec![1, 2, 3]; let result = process_closure_capture(data); println!("{:?}", result); }

Variable inaccessible after closure use in Rust

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