Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!apple!netcom!cooper
From: cooper@netcom.UUCP (Ken Cooper)
Newsgroups: comp.lang.smalltalk
Subject: Re: ST V/286 bl... globals
Message-ID: <4807@netcom.UUCP>
Date: 2 Dec 89 06:59:14 GMT
References: <453@DB0TUI11.BITNET>
Reply-To: cooper@netcom.UUCP (Ken Cooper)
Organization: NetCom- The Bay Area's Public Access Unix System {408 997-9175 guest}
Lines: 31

In article <453@DB0TUI11.BITNET> MUHRTH@DB0TUI11.BITNET (Thomas Muhr) writes:
>How can I recover from a system state which I have produced by
>mistakenly creating a Smalltalk at:xxxx variable which formerly pointed
>to a Class!.

One way of accomplishing this is to get ahold of the class, reinstall it in
Smalltalk, then remove it with a ClassHierarchyBrowser.  The only trick is
getting ahold of the class.

One way to do so is to get it out of a global array called TableOfClasses, 
which is an *ugly* data structure containing both classes and integer values
(the integers are pointers to the next free slot in the array).  Here's a
bit of code that will do what you want:

	TableOfClasses do: [ :class |
		((class isKindOf: Behavior) and: [ class name = 'Junk' ])
		        ifTrue: [
	        	    Smalltalk at: #Junk put: class.
			].
	]

This works on both Smalltalk/V 286 and Smalltalk/V Mac.

Hope this helps,

Ken

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Ken Cooper                                         USENET: cooper@netcom.uucp
Acumen Software                                Compu$erve: 71571,407
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