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Thread Subject:
The class file for ... has been changed; but the change cannot be applied

Subject: The class file for ... has been changed; but the change cannot be applied

From: Matt J

Date: 23 Jul, 2013 20:51:11

Message: 1 of 1

"The class file for ... has been changed; but the change cannot be applied because objects based on the old class file still exist."

I typically get the above warning after editing a class and it is very familiar to me. In particular, I also know that deleting all instances of a class or issuing "clear classes" gets rid of this warning. However, I am wondering if there is any more specific information available about when not clearing the class is really dangerous.

For example, I find that simply editing a class method never seems to produce any ill consequences. The changes I make to the method always seem to go through in spite of the warning. Can I always count on this? Might it only be changes to properties and class attributes that matter?

It would be convenient if that were the case. 99% of the time, I invoke this warning due to editing a class method while objects of the class are still in the workspace. It would be nice to know that I can safely ignore the warning, since deleting/reconstructing instances of the class every time I need to revise a class method is somewhat of a bother.

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