i love they manner in which you summarized more then 10 years of struggles, and introduce the high hopes that this future beholds... thanks Marcus! Fernando On Thu, Oct 4, 2012 at 9:16 AM, Sven Van Caekenberghe <sven@stfx.eu> wrote:

Thanks for the explanation and pointers, Marcus.

Well written, well said, as usual ;-)

-- Sven Van Caekenberghe http://stfx.eu Smalltalk is the Red Pill

On 04 Oct 2012, at 08:26, Marcus Denker <marcus.denker@inria.fr> wrote:

...

On Oct 4, 2012, at 8:02 AM, Marcus Denker <marcus.denker@inria.fr> wrote:

...

Now there are two philosophies

1) we load the new in addition. It even is compatible to many different versions of the System, and everyone uses it in new code. But the sytem can not use it, as the developer of course wants to load the latest version of this independendly develpopped library. Some people requested that for FileSystem, and we renamed all classes so that they can continue to load the code themselves.

This actually is interesting, these two philosophies...

1) The Addition View

Smalltalk is perfect and finished. Everything we do we do "on top". If we implement Morphic, we keep MVC. Things like FileSystem code is there as an additonal library. When doing research, the picture you have is not that of a System that you improve to make a new System that makes the next research easier. No. You do something *on top*, and throw it away after.

2) The System View

I think some people's brain kind of got a hickup when they looked at instances of Class and saw that they just use standard libraries. MethodDictionay is a Dictionary... there is no special "I wrote everyhting again because I am clever!" code even deep in the system. That is one of the things that makes Smalltalk powerful!

The main reason is that it created a feedback loop: We improve something for an application. But then, instead of throwing it away, we *apply* that improvement to the *whole* system. The system gets better (faster, smaller). And its expressiveness is improved: the next developer can just *use* the improvement and put the time into something else.

Especially in Research, this is quite important: You can't publish things that have already been done. Time is limited (just 3-4 years to do a PhD...). So if the guy has to constantly start from scratch, this gets very hard after just some interations. Yet, when the System itself improves... the picture here is that of a mountain: We can always climb up from the valley deep down, or we can build base camps. Who will do better?

I think we are starting to (slowly) see this with Pharo. E.g. the on-demand loading of the .sources. It uses Zinc and FileSystem, it's just a couple of lines of code. Yes, you could have done it before. But would anyone do it? Of course not. (just a very trivial example).

Marcus

-- Marcus Denker -- http://marcusdenker.de