[erlang-questions] Erlang modelling question

[Ben Butler-Cole]

Darius Bacon said:
> If the goal is to code mutable objects with inheritance,
> the most straightforward way seems to be with a process
> for each level of inheritance for each object.

Another way of doing something similar is to use a sort of strategy module as below. These different approaches will be suitable in different circumstances. This multiple processes approach will better if the 'subclass' needs to maintain its own state.

Ben


%%%-------------

-module(animal).

create(Module) ->
    spawn(fun() -> loop(Module) end).
loop(Module)
    receive
        {talk, From} -> From ! Module:talk(), loop(Module)
    end.


%%%-------------


-module(sheep).

create() ->
    animal:create(sheep).
talk() ->
    baa.


%%%------------


-module(cow).

create() ->
    animal:create(cow).
talk() ->
    moo.