Not wrong, only slightly inaccurate. The state that a process maintains via the process runloop is never mutated. The runloop is a recursive function, returning a new value into itself each time around the receive “loop”.
Also note that we don’t actually have loops in Elixir, Erlang or BEAM languages since valid bytecode is not allowed to “jump backwards” and therefore it cannot get “stuck” without yielding in a potentially infinite loop inlike almost all other languages I am aware of. The BEAM bytecode can only call another function and that is also how preemption is meticulously enforced through precise “reduction accounting” and why the BEAM provides such low latency. Even bad code cannot block work and processes can always be killed without cooperating and ruining a global “OO state graph” and leaving locks everywhere.
The important thing is that both state and execution context is bound together with real encapsulation. That is not the case in “OO languages”, as Joe’s Armstrong famously said in the book Coders at work:
I think the lack of reusability comes in object-oriented languages, not functional languages. Because the problem with object-oriented languages is they’ve got all this implicit environment that they carry around with them. You wanted a banana but what you got was a gorilla holding the banana and the entire jungle.
Yes you are correct. BEAM languages like Erlang and Elixir are the epitome of object oriented.
Alan Kay the father of the term object oriented said that Erlang is the most object oriented language.
The fact is that object oriented languages are not object oriented according to Alan Kaye’s definition.
OOP to me means only messaging, local retention and protection and hiding of state-process, and extreme late-binding of all things.
Alan said he imagined objects as biological cells communicating only via messages like computers on a network.
Well that describes an Elxir or Erlang process cluster communicating using only messages. Don’t you think?
Joe Armstrong thought so…
Erlang has got all these things. It’s got isolation, it’s got polymorphism and it’s got pure messaging. From that point of view, we might say it’s the only object oriented language.
I think perhaps there could be some room for object-splaining in order, however…
… it might be confusing, confronting and potentially create congnitive dissonance for many to say Elixir is a true object oriented language to those who have been conditioned to what they believe OO is.
