Re: Exceptions and Objects

On Sun, Aug 13, 2000 at 07:27:47PM -0700, Peter Scott wrote:
> At 12:22 PM 8/12/00 -0500, Jonathan Scott Duff wrote:
> Pretty much.  It screams O-O for these reasons:
> 
> An exception is an 'error'.  That's already a vague concept.
> 
> An error has text associated with it, but also a bunch of other attributes.

So it's a structured data type ... where does OOP come into play?

> They fall naturally into different classes, some of which have subclasses 
> (a File error is-a IO error).

This, to me, seems a mere matter of naming.  Was it that OOP already
had a hierarchical naming system and so it was used?

> Users want to define their own kinds while reusing the semantics of the 
> base class.

What does it mean for an exception to have semantics?  When an exception
is thrown does something special happen whether it's caught or not?

I have only a passing familiarity with exception handling and have only
used it in "toy" programs.  I'm just trying to wrap my mind around the
whys and wherefors.  I understand how it works, but not why it works
the way it does, any references to exception handling would be much
appreciated.

-Scott
-- 
Jonathan Scott Duff
[email protected]