Re: On the case for exception-based error handling.

[Peter Scott]

At 02:00 PM 8/22/00 -0600, Tony Olekshy wrote:
>Peter Scott wrote:
> > I actually see nothing wrong in division returning undef for a
> > dividend of 0.  It's just as easy to check as doing an eval.
>
>Please don't do this.  I would have to check every divide in all
>my code, since no fatal is the default!  Leave the current version
>of Perl's best guess as to what it should die on alone, unless
>use fatal is in scope.  Consider this:
>
>     $amount_i_owe_you = $gross_amount / $discount_rate - $paid;
>
>If $discount_rate is accidentally undef and $paid is $100, then the
>$amount_i_owe_you is now -$100.  I don't see my cheque yet ;-)

But surely you have to be consistent.  I understood Chaim's point to be 
that he wanted no exceptions if he didn't ask for them.  If the core 
currently dies where it could return and set $!, then it is being 
inconsistent, since this is not an error that prevents perl from 
continuing.  How can Chaim or anyone else write a program and know that it 
won't die if we allow such things to continue?

I suppose we could have a

         use Fatal qw/legacy/

Yuk.

--
Peter Scott
Pacific Systems Design Technologies