find_many.ex

def find_many(list, funs), do: do_find_many(list, funs |> Enum.map(&({&1, nil})))

defp do_find_many([h | t], funs, acc) do
  new_funs = funs |> Enum.map(
    fn {fun, nil} -> if fun.(h), do: {fun, h}, else: {fun, nil}
       other      -> other
    end)
  if Enum.any?(new_funs, fn {_, x} -> is_nil(x) end), do: t, else: []
  |> do_find_many(new_funs)
end

defp do_find_many([], funs) do
  new_funs |> Enum.unzip |> elem(1)
end