----- Original Message -----
From: Adam B. Roach <[EMAIL PROTECTED]>
To: "Barry (work)" <[EMAIL PROTECTED]>
Cc: <[EMAIL PROTECTED]>
Sent: Monday, April 24, 2000 3:59 PM
Subject: Re: Lessons learned...
> >As a general point, about the need for parsers to be forgiving - there is
an
> >argument that 'over-aggressive' parsers are useful because they prevent
> >unpredictable and potentially serious operational problems
> >from arising in a complex interworking environment.
>
> I'm not sure I agree. Can you give an example of the concern you
> beleive you're addressing?
>
Let's say a forgiving parser in system A passes some crud on to another
system B. A has no knowledge of how B will react to anything that is
outside the spec. Nor does A know, for example, whether or not the systems
are in a safety-critical situation. The only reasonable assumption A should
make about B is that B is responsible for performing correctly within the
spec. i.e. that given correct input, B should behave correctly, and that
given incorrect input, B will behave unpredictably.
Barry Desborough, VegaStream Ltd.
[EMAIL PROTECTED]
