Subject: Re: some input on sieve-00

From: Steve Hole <[email-masked]>
Date: Mon, 28 Apr 1997 17:43:34 -0600 (MDT)

On 26 Apr 1997 16:34:17 -0000 [email-masked] wrote:

> On the readability front,
> 
> I would like to see an optimization made to the grammar.  In the elements
> of an if-clause condition that use a list as an argument, I would like to
> see the ability to not necessarily have the parens for single-item lists.
> It might also be nice for users to not have to use quotes around words that
> don't need them.

We don't want to get too crazy on the readability front.   In practise, a 
GUI rule builder will be the interface for novice users wanting simple 
things and advanced users will just directly edit the language.

We want to keep this thing parseable.   The parens stripping I can live 
with because that is all semantic analysis anyway, but stripping the 
quotes means two different token types and doubling of the parser trees.  
Let's not do that.

Cheers.
---  
Steve Hole			VP,  Research and Development  
The Esys Corporation		EMail: [email-masked]
900 10040 - 104 St.		Phone: 403-424-4922  
Edmonton, AB, Canada		Fax:   403-424-4925  
T5J 0Z6

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From: Steve Hole <[email-masked]>
Date: Mon, 28 Apr 1997 17:43:41 -0600 (MDT)

On Sun, 27 Apr 1997 20:59:36 -0700 (PDT) Ned Freed 
<[email-masked]> wrote:

> > 6. Errors in Processing a Script
> 
> > The stipulation that implementations SHOULD NOT try to recover from a
> > script with errors is a problem for me.  Aborting within an 'if' clause
> > makes sense to me, but to totally stop filtering if any error is encountered
> > is the wrong thing to do.  I would venture a guess that most users would
> > consider this a very bad characteristic of the mechanism.
> 
> The problem with tring to recover is that you cannot be sure of what the user
> meant and you may end up doing the wrong thing. And in this case the wrong
> thing may mean losing mail.
> 
> However, as a purely practical matter I think this is largely a moot point,
> since I expect most implementations to perform syntax checking at the point 
> where rules are added. I know my implementation will do this.

Exactly.   Remember that in the worst case scenario, mail gets delivered 
to the user's inbox.

Cheers.
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