[fizixer]

Two sides to every story.

What is not beautiful is that:

- the people who conceived the original idea of the 'Actor model' were not appreciated enough, and their work had to languish in obscurity, during the OO (object-oriented) hype era, before it was rediscovered and later the dots were connected.

- 'reinvention of wheels' is bad because it's inefficient.

- Not to mention original OO idea by Alan Kay, in Smalltalk, was actually the 'Actor model' but it ended up being very misunderstood when implemented in C++, Java, etc, with the term OO being hijacked.

[rdtsc]

> 'Actor model' but it ended up being very misunderstood when implemented in C++, Java, etc,

Yap here it is right from the horse's mouth, so to speak:

https://computinged.wordpress.com/2010/09/11/moti-asks-objec... (see comments history)

---

If you are doing “simulated data structure programming” rather than object oriented programming. One of my original motivations for trying to invent OOP was to eliminate imperative assignment (at least as a global unprotected action). “Real OOP” is much more about “requests”, and the more the requests invoke goals the object knows how to accomplish, the better. “Abstract Data Types” is not OOP!

...

Many of Carl Hewitt’s Actors ideas which got sparked by the original Smalltalk were more in the spirit of OOP than the subsequent Smalltalks. Significant parts of Erlang are more like a real OOP language the the current Smalltalk, and certainly the C based languages that have been painted with “OOP paint”."

---

There you have it folks, Erlang is more OO than C++/Java and C#. It is kind of a funny tidbit, good for sharing during meetups over beers.

One interesting response to that I heard from a developer was "Well, it doesn't matter what Kay thinks anymore. C++/Java/C# got so popular and that is OO now officially".

[bryanrasmussen]

I guess I would have to agree with the unnamed developer, common usage means that OO is C++/Java and C#, hacker is a negative thing, and decimate just means to reduce by a significant portion not reduce by a tenth exactly. Perhaps to the detriment of all these terms.

[Diederich]

All of this reflects my thoughts on the matters, and I've been waiting more than 15 years for the co-called Actor model to 'come around', grieving the use of the term 'Object Oriented' in the meantime.

This comes across as strongly worded, but I'm going to let it stand, given the understanding that the C++ and Java style of 'Object Oriented' has value in a lot of situations and circumstances. Though I have leaned very heavily on Kay's 'Actor Model' over the years, C++ style OOP has also been useful from time to time.

[lectrick]

As someone who has only recently (finally) become disillusioned by OO (especially in larger codebases and/or on programming teams, which both seem to rapidly escalate tech debt and complexity thanks to things like mutability, class reopening and stowing-state-everywhere)... I'm so sorry, man. The difference (which is significant) unfortunately seems to require years of real-world experience with both to see it.

I've been pointing OO people to these thoughts by John Carmack, who is pretty well-respected in the C++ OO community: http://gamasutra.com/view/news/169296/Indepth_Functional_pro...

[Diederich]

I learned to program well before OO became The Thing, so when it came around, I had a foundation to consider it with a broader perspective.

Re: "I'm so sorry, man." Thanks, but I'm not sorry at all. The (what I call) Message Oriented Programming first approach has allowed me to have a highly successful career.

Re: Carmack. There's quite a few such highly respected and respectable articles out there, but I gave up advocacy a long, long time ago. I just let what I'm doing, and not doing, do the talking, for better and worse.

[lectrick]

Don't be jaded! Stay excited! You were way ahead of the curve! ;)

[Diederich]

Thanks for that! I'm not jaded, just realistic.

I'm actually working at a startup now that I found very interesting, mostly because it's based on flow-based programming paradigms:

https://flux.io/

[signa11]

> Not to mention original OO idea by Alan Kay...

i was kind of curious about this statement, so i looked up the history of programming languages (http://cdn.oreillystatic.com/news/graphics/prog_lang_poster....).

if you take a look, it would seem to _suggest_ that smalltalk borrows from both simula-67 and lisp. wikipedia page for simula-67 suggest that it (simula-67) "introduced objects, classes, inheritance and subclasses, virtual procedures, coroutines and discrete event simulation, and features garbage collection..."

now it might be just possible that simula-67 was the first language to incorporate those features in a language, and that alan-kay originally came up with that idea, waaay before simula-67 came into being.

[alankay]

No, I didn't come up with the idea before Simula -- but it did happen before Simula-67 (which doesn't matter at all here).

How it happened is well chronicled in the history paper I was asked to write by the ACM in 1992-3 "The Early History of Smalltalk" (i.e. why speculate when most high res answers are available online?). Ivan Sutherland's Sketchpad was the big first hit for me in 1966, and I saw the first Simula a week later.

Some of the confusion here is explained in the above link I wrote explaining that what is called "O-O" is nothing like I had in mind. The term was "colonized" because what we had been doing at Parc was powerful and we called it "object-oriented". But the "low-pass filter of O-O" was that Bjarne Strousrup decided to "do to C what had been done to Algol to make Simula". This was a perfectly reasonable idea. We were quite a bit more radical at Parc because we needed enormous amounts of expressability to invent personal computing (and we could and did design and build hardware that was matched to the radical ideas).

An interesting historical note is that the two inventors of Simula had completely different views of what they were doing and how it should be used for programming. Dahl was brilliant and conservative, and later wrote papers about using class definitions to make Abstract Data Types (and that is how a lot of so-called OOP programming is done today). Nygaard on the other hand was quite a wonderful wild man and visionary -- beyond brilliant -- and was into the abstract "simulate the meaningful structures" idea. Dahl was trying to fix the past and Nygaard was trying to invent the future.

During the 1978 HOPL conference time, we were visited at Parc at two different times, first by Dahl and Tony Hoare, to whom I showed and tried to explain Smalltalk: they didn't get it, and this was very frustrating. A few days later Nygaard showed up, and it was completely different: he got everything, and was finishing my sentences after 5 minutes!

Back to the origins in '66: besides the biological metaphors I had under my belt, I was also interested in the "virtual machines" ideas that were being used to do multi-processes and time-sharing in a safe way via hardware memory protection schemes (none of which I had had any involvement with inventing). One of the things that popped into my head while contemplating Sketchpad and Simula was that it would be just incredibly good -- and a huge improvement in systems designs -- to be able to use protected processes as the sole building blocks communicating only by messages that were not commands, but only "suggestions".

I think I'd call this not an invention, but a "realization" -- that the recursive machine idea was already around, and what it lacked was scalability downwards, so that all entities could be "protected virtual machines". A lot of what I now have to call "real OOP" turned out to be some years of software engineering in order to create a practical systems material that could scale in all directions.

[lobster_johnson]

I had no idea that Dahl and Nygaard ever visited you at PARC, that's fascinating. Growing up in Norway and learning programming in school, Simula was revered as a proud if distant national accomplishment, in an field where there weren't much else to be proud of (though this was also around the time when Norsk Data [1] collapsed, and people weren't really talking about how innovative they had been). I wish I had learned about Smalltalk back then; I didn't really look closely at it until I learned Objective-C.

[1] https://en.wikipedia.org/wiki/Norsk_Data

[lectrick]

"Throughout its history Norsk Data produced a long string of extremely innovative systems, with a disproportionately large number of world firsts."

Still seems like something worth being proud of. It just got sideswiped by the personal computer industry (a lot of things did).

[lobster_johnson]

Definitely. For example, not a lot of people know that Tim Berners-Lee developed his first hypertext system, ENQUIRE, an ND machine (the NORD-16 minicomputer running the operating system SINTRAN) [1].

[1] http://history-computer.com/Internet/Maturing/Lee.html

[strmpnk]

I think it relates to the idea that "Object Oriented" meant message passing (methods) between entities (objects). Not the meaning that was derived over time as programming languages borrowed select ideas from Smalltalk and then considered themselves OO because of feature similarity.

These days it's hard to argue for correcting the features that people label as OO. It's part of history at this point. It is still interesting to note that there was a slightly different intention when Alan Kay coined the term though. Perhaps we need a new label. Kay-OO or something.