Is it possible in an XML schema to say that an attribute is valid only
when it references another attribute in some other element (similar to
IDREF but with strings)?
For example, say I have an element a with a string attribute foo. Is
it possible to define an element b with an attribute bar whose only
permitted values are the values of foo?
As a further example, suppose I have
<a foo="123"/>
<a foo="456"/>
in one document and
<a foo="abc"/>
<a foo="def"/>
in another
How can I make bar only permit "123" and "456" in the first document
and "abc" and "def" in the other?
--
I am only a mirage.
