// access the "old" `line` again.
let line = line.unwrap();
// Now that we have our `String`, we want to make it an `i32`.
+ //@ We first `trim()` the `line` to remove leading and trailing whitespace.
//@ `parse` is a method on `String` that can convert a string to anything. Try finding it's documentation!
//@ In this case, Rust *could* figure out automatically that we need an `i32` (because of the return type
//@ of the function), but that's a bit too much magic for my taste. We are being more explicit here:
//@ `parse::<i32>` is `parse` with its generic type set to `i32`.
- match line.parse::<i32>() {
+ match line.trim().parse::<i32>() {
//@ `parse` returns again a `Result`, and this time we use a `match` to handle errors (like, the user entering
//@ something that is not a number).
//@ This is a common pattern in Rust: Operations that could go wrong will return `Option` or `Result`.
let line = line.unwrap();
// Now that we have our `String`, we want to make it an `i32`.
- match line.parse::<i32>() {
+ match line.trim().parse::<i32>() {
Ok(num) => {
unimplemented!()
},