match

rust/book/src/main.rs

@@ -34,6 +34,14 @@ enum Number {
    NaN
}
fn print_num_type(num: Number) {
    println!("{}", match num {
        Number::Integer(_) => "integer",
        Number::Float(_) => "float",
        Number::NaN => "not a number"
    })
}
fn main() {
    let x = 5; // x: i32
@@ -73,5 +81,10 @@ fn main() {
    let i: Number = Number::Integer(3);
    let f: Number = Number::Float(3.1415);
    let n: Number = Number::NaN;
    println!("Here are some numbers: {:?}, {:?} and {:?}", i, f, n)
    println!("Here are some numbers: {:?}, {:?} and {:?}", i, f, n);
    // match
    print_num_type(i);
    print_num_type(f);
    print_num_type(n);
}