[squeak-dev] SmalltalkImage current vs. Smalltalk

Stéphane Rollandin lecteur at zogotounga.net
Tue Mar 2 12:18:55 UTC 2010

> As noticed by Ronald, the main problem with SmalltalkImage is that it
> does not represent any Object indeed...

It represent some meta-information about the Smalltalk system, aspects 
of the system seen from outside so to say. It can not really be an 
object semantically on par with the others, but that information must be 
provided somehow.

AFAIC I see no actual problem here, better a question of taste 
concerning where the meta-info should be stored and how it should be 

> Though, when I see code like (Smalltalk cleanUpUndoCommands), ...

That's the user (that is, the outside) ordering the system to do 
something. It fits in my view of what SmalltalkImage represents.

Concerning Andreas question, I would keep globals in Smalltalk (since it 
is the SystemDictionary) and put everything else in SmalltalkImage that 
I would rename Squeak because it's nicer (and also because the image is 
only a part of the system, along with the VM for example).

Or we could just reify everything, and have classes Image, Changes, 
Sources, VM, Platform, User... why not ? we already have DisplayScreen 
("There is only one instance of me, Display. It is a global and is used 
to handle general user requests to deal with the whole display 
screen."). It could be fun.

my 2 cents...


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