but that would
depend on (say)
 -letter x (3, 5)
not being ambiguous.

As I mentioned, anything that requires whitespace around an operator would mean a new, more complicated, approach to whitespace. It would also make the repetition operator's syntax different from that of "*" and "+", which I think is not a good thing.

As for interleaving, don't we already have that with separators?

BTW

****************************************************

Dr. Bethan Tovey-Walsh

linguacelta.com

Golygydd | Editor geirfan.cymru

Croeso i chi ysgrifennu ataf yn y Gymraeg


On 1 Dec 2025, at 23:18, Liam R. E. Quin <liam@fromoldbooks.org> wrote:

On Mon, 1 Dec 2025 22:22:33 +0000
Bethan Tovey-Walsh <bytheway@linguacelta.com> wrote:

I don't see a problem with using "&" as an operator,
i'd rather keep & free in case interleaving is later wanted.
Use of & would also make it slightly harder to embed iXML in XML.

My first thought was actually × or x, ala good old Perl, but that would
depend on (say)
 -letter x (3, 5)
not being ambiguous.

Allowing a range operator other than comma may also help -

 -letter x (3 .. 5)
for example.

Although i suggested @ i don’t have strong feelings really, whatever
works. iXML is already far enough away from BNF/EBNF that people have
to learn it.



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