Re: RISC

[Robert A Duff <bobduff@world.std.com>]

"Marin David Condic" <marin.condic.auntie.spam@pacemicro.com> writes:

> Its hard to come up with absolute rules since it often requires subjective,
> artistic judgements. Just keep in mind that the intention is to have a
> mechanism that deals with *errors* - not anticipated conditions that can be
> accommodated with some sort of "normal" processing.

Which leaves open the definition of "error".  Different folks have
different notions of error.

I think the point of exceptions is that whether a given condition is an
"error" depends on your point of view.  Eg, a data structure package
that has a Remove_Item operation: if the data structure is empty, that's
an error, and an exception is appropriate.  But from the point of view
of the client, this situation might be "normal" or might be a bug --
it's the programmer's choice.

Another way to look at it is that the point of exceptions is to separate
the code that *detects* errors from the code that *handles* those
situations.  If the code that detects something knows what to do about
it, then exceptions aren't necessary -- that code can just have an 'if'
statement that checks the condition, and handles the situation in the
'then' part.

- Bob