cpp-peglib/language/culebra/samples/fib.cul

/*
 * Fibonacci
 */

fib = fn (x) {
    if x < 2 {
        x
    } else {
        self(x - 2) + self(x -1)
    }
}

mut i = 0
while i < 30 {
    puts("{i}: {fib(i)}")
    i = i + 1
}