Saving morph books....
mmayfield at nuforia.com
Fri Aug 20 02:42:43 UTC 1999
As for fixing the problem...this seems like it will be an error for
anyone trying to save a book morph to a file so I'm confident it will
be fixed by the masters.
>On Thu, 19 Aug 1999 17:09:41 -0500 "Mark Mayfield"
><mmayfield at nuforia.com> wrote:
>>When I inspect the objects within the debugger, each is a
>>PasteUpMorph object, BUT aUniClass is a MorphObjectOut. When a
>>MorphObjectOut is sent the message isSystemDefine, I get the error.
>>Why wouldn't the assignment aUniClass := each class not assign
>>aUniClass the class of the object referenced by each?
>Here's the short answer which may not do a lot to solve the problem,
>but which may keep you from going nuts looking at this.
>MorphObjectOut is a proxy class, i.e. instances of it are used to
>represent instances of other Classes which may not be available
>(like they are on disk and not yet read in). To do this, it
>implements #doesNotUnderstand: and uses that as a cue to get the
>real object and become: that object. The problem is that #class is
>one of those few messages which are dispatched directly from
>bytecodes and not through normal method lookup routines (try
>overidding #class in some Class and see if it ever gets hit). So,
>while 99.999% of messages to an instance of MorphObjectOut get
>forwarded to, and answered by, the real object, #class gets answered
>by the VM on behalf of MorphObjectOut with unfortunate effects. I
>haven't looked into the intent of the code at work here, so I cannot
>give you a guaranteed solution at this time, but here is what I
>1. Implement in Object
> ^self class
>2. Change the line in the method you referenced to read:
> (aUniClass := each realObjectClass) isSystemDefined ifFalse: [
>and see if that works.
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