RE: DOCBOOK: DocBook 4.0: ClassSynopsis

[Peter Ring <PRI at cddk dot dk>]

In Python, there are two exception styles in Python; old-style 
string objects (match on object identity) and new-style class 
instances (match on class or base class). You must be able to 
describe exceptions that are not classes, as well as classes 
that are used for exceptions.

kind regards
Peter Ring

-----Original Message-----
From: Fred L. Drake, Jr. [mailto:fdrake@acm.org]
Sent: Wednesday, December 22, 1999 10:11 PM
To: docbook@lists.oasis-open.org
Subject: Re: DOCBOOK: DocBook 4.0: ClassSynopsis

Norman Walsh writes:
 > Is the following observation correct: there's no dispute about
 > the semantics for exceptions or interfaces, the only point of
 > contention in the current proposal is whether or not
 > superclasses need to be called out in some more explicit way
 > than order among siblings.

  I think that's roughly right, though your asking and our discussion
to this point makes me think that the set of superclasses / interfaces 
should be separate from the set of allowed exceptions.  This is mostly 
a result of wanting to allow "exceptions" which are distinct from
"classes" (which *is* the case for Modula-3, but there is no concept
of exception inheritance: exceptions cannot be derived from other
exceptions) [note: I'm not actually aware of any language which
distinguishes exceptions from classes *and* supports exception
inheritance].
  If DocBook is to support such languages, there needs to be a marked
separation between what something is (superclasses & "implements"),
and what exceptions can be raised by constructors.  That might be the
way out:  the class itself doesn't raise exceptions, only it's
methods.

  -Fred

--
Fred L. Drake, Jr.	  <fdrake at acm.org>
Corporation for National Research Initiatives