Re: Grammar analysis

Hi all, What would be the most straightforward choice for empty terminal? I
would vote for something that is hard to get wrong and easy to get right
and pretty memorable, whatever that might be. As an outsider looking in, I
would want to be able to say to myself, "oh, that makes sense", if I need
that particular terminal.

My concern is loading that purpose on a specific character is rather
esoteric.
Regards, Dorothy

On Sat, Aug 26, 2023, 7:35 PM Liam R. E. Quin <liam@fromoldbooks.org> wrote:

> On Sat, 2023-08-26 at 18:38 -0400, Graydon wrote:
> > On Fri, Aug 25, 2023 at 05:09:59PM +0100, Norm Tovey-Walsh scripsit:
> > > <aside>
> > > I think we should introduce a required terminal for “empty”.
> > > One candidate is ε:
> > >
> > >  rule: name, "=", value; ε .
> > >
> > > but there lots of other possibilities as well.
> > > </aside>
> >
> > One vote from the peanut gallery strongly in favour.
> >
> > ∅ (U+2205 EMPTY SET) might be another character possibility.
>
> In Yacc days people used to use
>
>    empty: /* empty */ ;
>
> as i recall (where /*....*/ denotes a comment). Or if not a specific
> production, just a comment, /* empty */.
>
> Maybe, in ixml,
>
>    -empty: .
>
> could help?? Then use empty in productions. Might make ambiguities
> though, hmm.
>
>
> The ixml syntax is already a little unusual, or at least i find it
> unfamiliar, and adding more symbols isn't going to help with that. But
> a styling convention might.
>
> --
> Liam Quin, https://www.delightfulcomputing.com/
> Available for XML/Document/Information Architecture/XSLT/
> XSL/XQuery/Web/Text Processing/A11Y training, work & consulting.
> Barefoot Web-slave, antique illustrations:  http://www.fromoldbooks.org
>
>