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> / "Michael Kay" <mike@s...> was heard to say: > | The XML specification does not use the term "semantic > structure". It uses > | the word "semantic" twice: > | > | (a) to say that it does not constrain the semantics of elements and > | attributes, other than those whose names beginning with "xml" > | > | (b) in 3.3.1, to say that the tokenized attributes such as > ID, IDREFS "have > | varying lexical and semantic constraints". > | > | These two statements are unfortunately contradictory, but > then it's unusual > | to find two uses of the word "semantics" that attach the > same meaning to the > | word. > > Indeed. I expect we can clarify that a bit. XML allows a document > (actually a document type definition) author to impose some lexical > and semantic constraints on attributes (by giving them the types ID, > IDREF, IDREFS, ENTITY, ENTITIES, or NOTATION). But in that case, it > isn't XML that makes the constraints, it's the DTD author. I think that what has actually happened here is that the first extract is using "semantics" the way it is used when discussing natural languages: it means "meaning" or "information content". The second extract is using "semantics" the way it is used in programming languages: it means "rules beyond those in the grammar". Michael Kay http://www.saxonica.com/
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