rustlings/exercises/error_handling/option1.rs

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// option1.rs
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// This example panics because the second time it calls `pop`, the `vec`
// is empty, so `pop` returns `None`, and `unwrap` panics if it's called
// on `None`. Handle this in a more graceful way than calling `unwrap`!
// Execute `rustlings hint option1` for hints :)
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pub fn pop_too_much() -> bool {
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let mut list = vec![3];
let last = list.pop().unwrap();
println!("The last item in the list is {:?}", last);
let second_to_last = list.pop().unwrap();
println!(
"The second-to-last item in the list is {:?}",
second_to_last
);
true
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}
#[cfg(test)]
mod tests {
use super::*;
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#[test]
fn should_not_panic() {
assert!(pop_too_much());
}
}