Re: What is a pragma?

Thank you, Norm and Bethan!

Norm Tovey-Walsh writes:

> We take the position that conformant interpretation of pragmas should
> not alter the semantics of an ixml grammar.

What does "the semantics of an ixml grammar" mean?

What does it mean to alter the semantics?

> (You can’t have a conformant pragma that changes the rules!)

How would that be enforced?

Is the enforcement mechanism that if someone defines a pragma that
changes the rules (whatever that might be taken to mean), other people
have the right to point at that pragma and say "that one is a
non-conforming pragma"?

Can preservation of the semantics be tested for?  Or will it require
human judgement?

> We think Tom and Michael
> might disagree and look forward to their spirited input :-)

Do pragmas in XQuery change the semantics of the query in which they are
embedded?  Or do they leave the semantics of the query as they are
defined by the XQuery spec alone, even when they request that processors
capable of evaluating the alternate expression inside the pragma
evaluate that expression in place of the 'fallback expression'?


Michael

-- 
C. M. Sperberg-McQueen
Black Mesa Technologies LLC
http://blackmesatech.com

Received on Friday, 28 January 2022 20:02:42 UTC