Re: DTD to Schema converter

Jeni Tennison writes:

>> As I understand it, elements with ANY content 
>> can have *any* content, *including* text content. 

No, I certainly don't think so.  Acceptance of text content is controlled 
by mixed/element-only, which is checked before you even look at the 
content model.  See [1] which says:

Validation Rule: Element Locally Valid (Complex Type) 
For an element information item to be locally ·valid· with respect to a complex type definition all of the following must be true: 
1 {abstract} is false. 
2 If clause 3.2 of Element Locally Valid (Element) (§3.3.4) did not apply, then the appropriate case among the following must be true: 
2.1 If the {content type} is empty, then the element information item has no character or element information item [children].
2.2 If the {content type} is a simple type definition, then the element information item has no element information item [children], and the ·normalized value· of the element information item is ·valid· with respect to that simple type definition as defined by String Valid (§3.14.4).
2.3 If the {content type} is element-only, then the element information item has no character information item [children] other than those whose [character code] is defined as a white space in [XML 1.0 (Second Edition)].
2.4 If the {content type} is element-only or mixed, then the sequence of the element information item's element information item [children], if any, taken in order, is ·valid· with respect to the {content type}'s particle, as defined in Element Sequence Locally Valid (Particle) (§3.9.4).

I think that 2.3 tells you that, regardless of whether there is <any> in 
the content model, text content is rejected if the type is element-only. 
Validation of element content proceeds after that check.

The general philiosphy is that mixed/element-only is a switch that's 
completely orthogonal to the actual declared content model. 

[1] http://www.w3.org/TR/xmlschema-1/#cvc-complex-type

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Noah Mendelsohn                                    Voice: 1-617-693-4036
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