curried

gistfile1.ex

defmodule Curried do
  defmacro defc({name, _, args}, [do: body]) do
    curried_args = Enum.map(Enum.with_index(args), fn({_, index}) ->
      Enum.take(args, index + 1)
    end)
    for a <- curried_args do
      if a == Enum.at(curried_args, Enum.count(curried_args) - 1) do
        quote do
          def unquote(name)(unquote_splicing(a)) do
            unquote(body)
          end
        end
      else
        quote do
          def unquote(name)(unquote_splicing(a)) do
            fn(next) -> unquote(name)(unquote_splicing(a), next) end
          end
        end
      end
    end
  end
end

defmodule CurriedTest do
  use ExUnit.Case, async: true

  defmodule CurriedExample do
    import Curried

    defc foobar(one, two, three) do
      one + two + three
    end
  end

  test "curries" do
    assert CurriedExample.foobar(1).(2).(3) == 6
    assert CurriedExample.foobar(1, 2).(3) == 6
    assert CurriedExample.foobar(1, 2, 3) == 6
  end
end

Very Cool. Just wish that this was part of Elixir standard.