Re: [xml-dev] xml-dev Digest 7 Nov 2013 14:35:15 -0000 Issue 2878

[Michael Kay <mike@saxonica.com>]

> 
> Some time later on, my brain fully exploded when I realised that there is no clean layered separation possible (at least that I could envisage) that would still give you all the features of full-on SGML.
> 
> Some time later on, I concluded that this is inevitably true in any powerful text processing system because semantics - real semantics - is on great big hermeneutic circle.
> 

XML could have achieved far better separation if it had chosen. The intertwingling of the physical and logical layers caused by the rule that elements must be well-balanced within entities is a quite unnecessary constraint on implementation modularity; the interactions between entity expansion and syntactic parsing within DTDs are even worse. I don't think it's at all true that these complications are inevitable.

Michael Kay
Saxonica