Recursive anonymous functions in Elixir

recursive_anonymous_function.exs

f = fn
  (_, 0, acc) -> acc
  (g, num, acc) -> g.(g, num-1, acc+1)
end

# f.(f,10,10)

# Source:  peerreynders at https://elixirforum.com/t/recursive-anonymous-functions/18421/4

"Functions are values …" Peer Reynders

# I went looking for it inspired by a message by "M G" at https://t.me/elixirES

# Fibonacci 

fib = fn
  (_, 0) -> 1
  (_, 1) -> 1
  (f, num) -> f.(f, num-1) + f.(f, num-2)
end

fib.(fib, 20)