Recursion and anonymous functions in elixir

Question

I\'m trying to define an anonymous function to do a dot product, I can code this as a private function without any problem but I am struggling with the anonymous function syntax

Answer 1

Here's a fixed (Y) combinator:

fix = fn f -> 
    (fn z ->
        z.(z)
    end).(fn x -> 
        f.(fn y -> (x.(x)).(y) end)
    end)
end

Here's how you use it:

factorial = fn factorial ->
    fn
        0 -> 0
        1 -> 1
        number -> number * factorial.(number - 1)
    end
end

fix.(factorial).(6) # 720

Only works with functions that recurse with 1 argument. Elixir doesn't have variable arguments. To support multiple arguments, you'll need to add more arguments than the single y like: f.(fn a,b -> (x.(x)).(a,b) end).