Hello all,
I was reading Kent Beck's "Guide To Better Smalltalk" and he has an article 
on Instance-specific behavior in it. In my endivors to get re-acquinted with 
Smalltalk, I remember doing similiar stuff while debugging windows. Anyway, 
it looked like a fun little thing to do. SO, I typed in the following in a 
workspace:

| class |
class:=Behavior new.
class superclass: Object methodDictionary: MethodDictionary new format: 
Object format.
class compile: 'dodo ^''ya ya'''.
inst:=class new.
inst perform: #dodo

If I inspect this, I get the following walkback:
MessageNotUnderstood: 
compile:notifying:trailer:ifFail:elseSetSelectorAndNode:
13 May 2002 9:25:45 pm

VM: Win32 - Squeak3.2gamma of 12 January 2002 [latest update: #4858]
Image: Squeak3.2gamma [latest update: #4857]

Behavior(Object)>>doesNotUnderstand:
	Receiver: a descendent of Object
	Arguments and temporary variables:
		aMessage: 	a Message with selector: 
#compile:notifying:trailer:ifFail:elseSetSel...etc...
	Receiver's instance variables:
		superclass: 	Object
		methodDict: 	a MethodDictionary()
		format: 	2

Behavior>>compile:notifying:
	Receiver: a descendent of Object
	Arguments and temporary variables:
		code: 	'dodo ^''ya ya'''
		requestor: 	nil
		method: 	nil
		selector: 	nil
		methodNode: 	nil
		sel: 	nil
		parseNode: 	nil
		f: 	nil
	Receiver's instance variables:
		superclass: 	Object
		methodDict: 	a MethodDictionary()
		format: 	2

Behavior>>compile:
	Receiver: a descendent of Object
	Arguments and temporary variables:
		code: 	'dodo ^''ya ya'''
	Receiver's instance variables:
		superclass: 	Object
		methodDict: 	a MethodDictionary()
		format: 	2

UndefinedObject>>DoIt
	Receiver: nil
	Arguments and temporary variables:
		class: 	a descendent of Object
	Receiver's instance variables:
nil
--- The rest of the stack ---
Compiler>>evaluate:in:to:notifying:ifFail:

Is this the correct behavior? (no pun intended). Anyway, so I looked for 
implementors of: #compile:notifying:trailer:ifFail:elseSetSelectorAndNode:. 
And I got a sole implementor at ClassDescription. So, I replaced Behavior 
with ClassDescription and voila it works! But, wait...take out the #perform: 
and do inspect-it on the code so it returns the inst variable. Now, in the 
inspector, type in the code: 'self perform: #dodo' and print-It. Now, I get 
a walkback with the following details:

MessageNotUnderstood: classPool
13 May 2002 9:32:56 pm

VM: Win32 - Squeak3.2gamma of 12 January 2002 [latest update: #4858]
Image: Squeak3.2gamma [latest update: #4857]

ClassDescription(Object)>>doesNotUnderstand:
	Receiver: a subclass of Object
	Arguments and temporary variables:
		aMessage: 	a Message with selector: #classPool and arguments: #()
	Receiver's instance variables:
		superclass: 	Object
		methodDict: 	a MethodDictionary(#dodo->a CompiledMethod (2207) )
		format: 	2
		instanceVariables: 	nil
		organization: 	('as yet unclassified' dodo)


FakeClassPool class>>adopt:
	Receiver: FakeClassPool
	Arguments and temporary variables:
		classOrNil: 	a subclass of Object
	Receiver's instance variables:
		superclass: 	Object
		methodDict: 	a MethodDictionary()
		format: 	2
		instanceVariables: 	nil
		organization: 	('as yet unclassified')

		subclasses: 	nil
		name: 	#FakeClassPool
		classPool: 	nil
		sharedPools: 	nil
		environment: 	nil
		category: 	nil

TextMorphEditor(ParagraphEditor)>>evaluateSelection
	Receiver: a TextMorphEditor
	Arguments and temporary variables:
		result: 	nil
		rcvr: 	nil
		ctxt: 	nil
		ex: 	nil
	Receiver's instance variables:
		model: 	an Inspector
		view: 	nil
		sensor: 	an EventSensor
		lastActivityTime: 	nil
		redButtonMenu: 	nil
		redButtonMessages: 	nil
		scrollBar: 	0 at 0 corner: 0 at 0
		marker: 	0 at 0 corner: 0 at 0
		savedArea: 	nil
		menuBar: 	0 at 0 corner: 0 at 0
		savedMenuBarArea: 	nil
		paragraph: 	a NewParagraph
		startBlock: 	a CharacterBlock with index 1 and character $s and rectangle 
0 at 0 co...etc...
		stopBlock: 	a CharacterBlock with index 20 and rectangle 114 at 0 corner: 
114 at 14
i...etc...
		beginTypeInBlock: 	nil
		emphasisHere: 	#(a TextFontChange font: 1)
		initialText: 	a Text for 'self perform: #dodo'
		selectionShowing: 	false
		otherInterval: 	(1 to: 0)
		morph: 	a TextMorphForEditView(2968)
		oldInterval: 	nil
		pivotBlock: 	nil

[] in PluggableTextMorph>>printIt
	Arguments and temporary variables:
		result: 	nil
		oldEditor: 	a TextMorphEditor

--- The rest of the stack ---
TextMorphForEditView(TextMorph)>>handleEdit:

Now, I do implementors on the classPool method and I get Class and some 
other classes to be implementors. I change my example from ClassDescription 
to Class and everything works beautifully! Now, I hate to be long winded to 
get to my question, but is this the way it is supposed to work? I thought 
behavior handles the format, methods, compiling, and superclasses. Very 
minimal. Anyway, it seems ClassDescription and Class are more than I want. 
Did I just find some bugs? I created a TempBehavior class and implemented 
classPool (simply returned nil) and compile:etc method (I actually used the 
ClassDescription implmentation and removed the code that added it to the 
changes file). This seemed to make the inst work in the inspector and 
everything seemed to work. Do we need to put these methods up in Behavior or 
at least abstract implementations?

It seems to me that at any rate, we would want the inspector to be able 
handle any instances of Behavior and not just Class instances. I'm just 
asking to make sure I'm not doing something wrong.

FYI, The code was taken pretty much from Kent's book and modified to fit 
Squeak.

I tried the example in Dolphin too and got a different set of errors.


Thanks for your time,
Blaine Buxton


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