[e12e]

Ok, now I see a little more of how things are connected. In my opinion, it would've been nice to be a) more explicit about the naming/aliasing of blue/orange in the final section, and b) Show how to actually read data sent from room2 in room1, eg:

    # Start session for room1, shoot orange portal in room1
    $ iex --sname room1 --cookie secrit -S mix
    iex(room1@COMPUTER-NAME)1> Portal.shoot(:blue)
    {:ok, #PID<0.67.0>}

    # Start session for room2, shoot orange portal in room2
    $ iex --sname room2 --cookie secret -S mix
    iex(room2@COMPUTER-NAME)1> Portal.shoot(:orange)

    # set up aliases/variables for blue/orange in room2
    iex(room2@COMPUTER-NAME)1> blue = {:blue, :"room1@COMPUTER-NAME"}
    {:blue, :room1@COMPUTER-NAME}
    {:ok, #PID<0.68.0>}
    iex(room2@COMPUTER-NAME)3> orange = {:orange, :"room2@COMPUTER-NAME"}
    {:orange, :room2@COMPUTER-NAME}

    # Use aliases to set up portal transfer in room2
    iex(room2@COMPUTER-NAME)4> portal = Portal.transfer(orange, blue, [1,2,3,4])
    #Portal<
      {:orange, :room2@COMPUTER-NAME} <=> {:blue, :room1@COMPUTER-NAME}
                    [1, 2, 3, 4] <=> []

    iex(room2@COMPUTER-NAME)5> Portal.push_right(portal)
    #Portal<
      {:orange, :room2@COMPUTER-NAME} <=> {:blue, :room1@COMPUTER-NAME}
                       [1, 2, 3] <=> [4]

    # set up aliases/variables for blue/orange in room1 (saves typing!)
    iex(room1@COMPUTER-NAME)2> orange = {:orange, :"room2@COMPUTER-NAME"}
    {:orange, :room2@COMPUTER-NAME}
    iex(room1@COMPUTER-NAME)3> blue = {:blue, :"room1@COMPUTER-NAME"}
    {:blue, :room1@COMPUTER-NAME}

    # Anything in the door?
    iex(room1@COMPUTER-NAME)4> Portal.Door.get(orange)
    [4, 3, 2, 1]
    iex(room1@COMPUTER-NAME)5> Portal.Door.get(blue)
    []

    #Switch to room2, push a value:
    iex(room1@COMPUTER-NAME)6> Portal.Door.get(blue)
    [4]
    iex(room1@COMPUTER-NAME)7> Portal.Door.get(orange)
    [3, 2, 1]

    # Verify that we're communicating, in room1:
    iex(room1@kuromaki)6> Portal.Door.get(blue)
    [4]
    iex(room1@kuromaki)7> Portal.Door.get(orange)
    [3, 2, 1]
   

I'm still not entirely clear on if it's possible to access the "portal" from both rooms [edit: to call push_right from room1 on the portal instantiated in the session in room2] -- could I get at it from room1 by qualifying it with room2@COMPUTER-NAME? If so what would the implications be? I assume functions are called via message passing, so this would be safe?

I think a lot of the stuff up to the very last bit is good, I just feel the article stops a little short. Maybe I just need to read it again (and play more with elixir).