Elixir Curry... is delicious

curry.exs

defmodule Math do

  def add(x, y) do
    x + y
  end

  def add(x, y, z) do
    x + y + z
  end

  def div(x, y) do
    x / y
  end

  def div(x, y, z) do
    x / y / z
  end

end

defmodule Curry do

  def arity(f) when is_function(f), do: arity(f, 0)
  defp arity(f, n) when is_function(f, n), do: n
  defp arity(f, n), do: arity(f, n+1)

  defp curryize(f, 0, args) do
    apply(f, args)
  end

  defp curryize(f, n, args) do
    fn x ->
      curryize(f, n-1, args ++ [x])
    end
  end

  def curry(f) do
    case n = arity(f) do
      0 -> f
      _ -> curryize(f, n, [])
    end
  end

  def curry2(f) do
    fn a ->
      fn b ->
        f.(a, b)
      end
    end
  end

end

Looks like my recursive solution for finding the arity of a function isn't even necessary. Just came across this:
https://groups.google.com/forum/#!topic/erlang-programming/sU7RtQm9qs0

So you could drop the arity function and write:

def curry(f) do
  case :erlang.fun_info(f, :arity) do
    {:arity, 0} -> f
    {:arity, n} -> curryize(f, n, [])
  end
end

Thanks for that! I've added it to a lib where I'm keeping these things...
https://github.com/mudphone/Hoex/blob/master/lib/hoex.ex