> In the long run, reading a book on
> Z, a book on XML and a Z-based XML spec is easier than trying to
> reconstruct the ideas in the authors heads based on imprecise prose. It's
> not like making an XML parser is a weekend job anyhow!
In the end, having an available judicial body who can be asked (and can
annotate the spec) is easier than all that. XML isnt so much an algebraic
thing a subject of human communication. People need to know what is an
error, and why. It is when they don't know why that the "what" is
unpredictable.
Sooner or later every specification has to be made in non-technical terms:
if people are confused by XML in semi-formal terms, I don't believe they
will be less mystified by XML in Z and Z specified in some other book itself
in semi-formal terms. (If they already know Z, then perhaps.)
In any case, if a lot of XML people freak out at DTDs, or even the draft XML
productions which extended EBNF, so what on earth will they make of Z (its
syntax certainly mystified me at Uni)? Perhaps things can only be
well-specified formally, but people can only have things specified by going
from what they know to what they do not know: initially this will be
informally. A spec has to use familiar notations if it is targetted at the
masses.
Rick Jelliffe