YCombinator Factorial in Erlang

gistfile1.txt

Eshell V5.9.1  (abort with ^G)
% The Y combinator allows recursion to be defined as a set of rewrite rules without requiring 
% native recursion support in the language.

c(y_comb_single).  % takes single param
{ok,y_comb_single}

(y_comb_single:y2(
    fun (F) ->
        fun(0) -> 1;
            (N) -> N * F(N-1)
        end
    end
))(3).


% --------------
-module(y_comb_single).
-export([y2/1]).
 
y2(F) ->
  (fun (G) -> G(G) end)(
    fun (G) ->
      F(fun (X) -> (G(G))(X) end)
    end
  ).