print "Hello, World!";

// Variables
let name = "Alice";       // immutable
var count = 0;            // mutable

// Functions
func greet(name) {
    print "Hello, " + name;
}

// Lambdas
let square = |x| x * x;

// Pattern matching
match (score) {
    0..60 => print "F";
    60..80 => print "C";
    80..100 => print "A";
    _ => print "Invalid";
}

// Classes and structs
class Person {
    let name;
    let age;

    func greet() {
        print "I'm " + this.name;
    }
}

// Lists and iteration
var nums = [1, 2, 3, 4, 5];
for n in nums {
    print square(n);
}

// Defer, try/catch, ranges, destructuring, spread, pipes, and more