Try module patching helpers

README.md

@@ -1,4 +1,4 @@
 Welcome to the home for [my personal livebooks](https://github.com/christhekeele/livebooks/tree/latest/livebooks): Elixir experiments, guides, and accompanying source code.
 
 Their history can be accessed [on GitHub](https://github.com/christhekeele/livebooks) by the clicking the "view source"
-`</>` icon next to the title of every page. Corrections, proposals, and discussions can be made in the GitHub [issues](https://github.com/christhekeele/livebooks/issues), [pull requests](https://github.com/christhekeele/livebooks/pulls), and [discussions](https://github.com/christhekeele/livebooks/discussions) pages respectively.
+`</>` icon next to the title of every page. Corrections, proposals, and discussions can be made in the GitHub [pull requests](https://github.com/christhekeele/livebooks/pulls), [issues](https://github.com/christhekeele/livebooks/issues), and [discussions](https://github.com/christhekeele/livebooks/discussions) pages respectively.

lib/livebook/helpers.ex

@@ -0,0 +1,55 @@
+defmodule Livebook.Helpers do
+  @moduledoc """
+  Common helpers for these livebooks.
+  """
+
+  defmacro __using__(_opts \\ []) do
+    quote do
+      import unquote(__MODULE__), only: [defmodule: 3]
+      unquote(__MODULE__).start_patching_modules()
+    end
+  end
+
+  @doc """
+  Inspired by [this macro](https://github.com/brettbeatty/experiments_elixir/blob/master/module_patching.livemd).
+  """
+  defmacro defmodule(alias, [v: version], do_block) do
+    [do: block] = do_block
+    module = Macro.expand(alias, __CALLER__)
+    version = Macro.expand(version, __CALLER__)
+    version_namespace = "v#{version}" |> String.to_atom()
+    module_namespace = Module.concat([:"Elixir", module, version_namespace])
+    store_block(module, version, block)
+
+    quote do
+      defmodule unquote(module_namespace) do
+        (unquote_splicing(patches_so_far(module, version)))
+      end
+
+      alias unquote(module_namespace), as: unquote(alias)
+    end
+    |> IO.inspect()
+  end
+
+  defp store_block(module, version, block) do
+    :ets.insert(__MODULE__, {{module, version}, block})
+  end
+
+  defp patches_so_far(module, version) do
+    __MODULE__
+    |> :ets.select([{{{module, :"$1"}, :"$2"}, [{:"=<", :"$1", version}], [:"$2"]}])
+    |> Enum.flat_map(&unblock/1)
+  end
+
+  defp unblock(ast)
+  defp unblock({:__block__, _meta, block}), do: block
+  defp unblock(ast), do: [ast]
+
+  def start_patching_modules do
+    with :undefined <- :ets.whereis(__MODULE__) do
+      __MODULE__ = :ets.new(__MODULE__, [:ordered_set, :named_table])
+    end
+
+    :ok
+  end
+end

livebooks/surreal.livemd

@@ -1,20 +1,38 @@
 # Surreal Numbers
 
 ```elixir
-Mix.install([
-  {:ets, "~> 0.9.0"},
-  {:eternal, "~> 1.2"}
-])
+Mix.install(
+  [
+    {:ets, "~> 0.9.0"},
+    {:eternal, "~> 1.2"},
+    {:livebooks, github: "christhekeele/livebooks", tag: "latest"}
+  ],
+  force: true
+)
+```
+
+## Video Format
+
+[Watch the ElixirConf 2022 lightning talk here!](https://www.youtube.com/watch?v=f1lNK5gDlwA&t=235s)
+
+## Helpers
+
+```elixir
+use Livebook.Helpers
+```
+
+## Caching
 
+```elixir
 require Logger
 
-defmodule Surreal.Guards do
+defmodule SurrealGuards do
   defguard is_set(surreals) when is_list(surreals)
 
   defguard is_surreal(surreal) when is_tuple(surreal) and tuple_size(surreal) == 2
 end
 
-defmodule Surreal.Cache do
+defmodule SurrealCache do
   @name __MODULE__
 
   def init() do
@@ -47,13 +65,9 @@ defmodule Surreal.Cache do
   end
 end
 
-Surreal.Cache.init()
+SurrealCache.init()
 ```
 
-## Video Format
-
-[Watch the ElixirConf 2022 lightning talk here!](https://www.youtube.com/watch?v=f1lNK5gDlwA&t=235s)
-
 ## Axioms
 
 * Zero
@@ -96,9 +110,9 @@ five_eighths = {[one_half], [three_quarters]}
 ## Module
 
 ```elixir
-defmodule Surreal do
+defmodule Surreal, v: 1 do
   import Kernel, except: [-: 1, +: 2, -: 2, *: 2, /: 2, <>: 2]
-  import Surreal.Guards
+  import SurrealGuards
 
   @zero {[], []}
   @one {[{[], []}], []}
@@ -108,9 +122,9 @@ end
 ## Set Concatenation
 
 ```elixir
-defmodule Surreal do
+defmodule Surreal, v: 2 do
   import Kernel, except: [-: 1, +: 2, -: 2, *: 2, /: 2, <>: 2]
-  import Surreal.Guards
+  import SurrealGuards
 
   @empty_set []
   @zero {@empty_set, @empty_set}