From: Hidetoshi NAGAI Date: 2003-11-12T11:27:13+09:00 Subject: Re: Ruby/Tk Some Basic Questions Hi, From: David D'Andrea Subject: Re: Ruby/Tk Some Basic Questions Date: Wed, 12 Nov 2003 03:05:00 +0900 Message-ID: <6840897E-1472-11D8-95C1-003065F62D66@sympatico.ca> > What is an abstract class? > I think of classes as abstract already, and objects as concrete. Maybe > an abstract class is one that never gets instantiated, but is always > further specified / subclassed before being used? Sorry. I'll have to say it differently. As you know, Ruby cannot define abstruct classes in the true sense of the term. TkWindow class is treated as an abstruct class. Therefore, instances of the class don't work as widget objects. In this sence, it is a bug that TkWindow objects can be created. I commited the patch to raise an exception when calling TkWindow.new. -- Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)