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// option1.rs
// 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`!
// Scroll down for hints :)
pub fn pop_too_much() -> bool {
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
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn should_not_panic() {
assert!(pop_too_much());
}
}
// Try using a `match` statement where the arms are `Some(thing)` and `None`.
// Or set a default value to print out if you get `None` by using the
// function `unwrap_or`.
// Or use an `if let` statement on the result of `pop()` to both destructure
// a `Some` value and only print out something if we have a value!
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