fun add(a, b) { a + b }
add(5, 3)

fun greet(name) { "Hello, " + name + "!" }
greet("Bob")

fun square(x) { x * x }
square(4)

fun max(a, b) { if a > b { a } else { b } }
max(10, 7)

fun factorial(n) { if n <= 1 { 1 } else { n * factorial(n - 1) } }
factorial(5)

let double = fun(x) { x * 2 }
double(6)

fun is_even(n) { n % 2 == 0 }
is_even(8)
is_even(7)