In Coconut

Here’s the code for defining an infinite list representing the Fibonacci series in Coconut:

def fib() = (0, 1) :: map ((+), fib(), fib()$[1:])

Note the use of the iterator chaining operator :: in this case to form the list.

Let’s break down this code, step-by-step to understand what exactly is going here. First, we defined our first two Fibonacci numbers to be (0,1) and we used the :: operator to concatenate the rest of the Fibonacci sequence. We use a higher order function map, by applying the (+) arithmetic operator in fib() and the rest of the elements fib()$[1:]

Obtaining the nth element is straightforward. Try finding the 20th element.

Show Solution:

In the next section, we'll take a look at implementing a factorial function.