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Struct usage error after partial move in Rust

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BugFind the bug and fix the code

What it should do

Process data within a struct and return a modified version. Example: process_partial_move(data) -> modified_data

What happens instead

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

struct DataHolder { data: String }

impl DataHolder {
    fn process_partial_move(mut self) -> String {
        let partial_data = self.data[0..5].to_string();
        self.data = self.data[5..].to_string();
        partial_data + &self.data
    }
}

fn main() {
    let holder = DataHolder { data: "hello world".to_string() };
    let result = holder.process_partial_move();
    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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struct DataHolder { data: String } impl DataHolder { fn process_partial_move(mut self) -> String { let partial_data = self.data[0..5].to_string(); self.data = self.data[5..].to_string(); partial_data + &self.data } } fn main() { let holder = DataHolder { data: "hello world".to_string() }; let result = holder.process_partial_move(); println!("{}", result); }

Struct usage error after partial move in Rust

What it should do

What happens instead

More scope and closure bugs to practise

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Struct usage error after partial move in Rust

What it should do

What happens instead

More scope and closure bugs to practise

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