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#[derive(Debug)]
enum UsState {
Alabama,
Alaska,
}
enum Coin {
Penny,
Nickle,
Dime,
Quarter(UsState),
}
fn value_in_cents(coin: &Coin) -> u8 {
match coin {
Coin::Penny => {
println!("Lucky penny!");
1
}
Coin::Nickle => 5,
Coin::Dime => 10,
Coin::Quarter(state) => {
println!("State quarter from: {:?}!", state);
25
}
}
}
fn main() {
let coin = Coin::Quarter(UsState::Alaska);
value_in_cents(&coin);
let mut count = 0;
if let Coin::Quarter(state) = coin {
println!("State quarter from: {:?}!", state);
} else {
count += 1;
}
fn plus_one(x: Option<i32>) -> Option<i32> {
match x {
None => None,
Some(x) => Some(x + 1),
}
}
let five = Some(5);
let six = plus_one(Some(5));
let none = plus_one(None);
let some_u8_value = 0u8;
match some_u8_value {
1 => println!("one"),
3 => println!("three"),
5 => println!("five"),
7 => println!("seven"),
_ => (),
}
let some_u8_value = Some(0u8);
if let Some(3) = some_u8_value {
println!("three");
}
}
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