I have three questions:
(1) Do XML files have to have the suffix ".xml", or is it just convention?
Do DTD files have to have the suffix ".dtd", or is it also just
convention? Does it depend on the XML processor?
(2) Suppose that you want to define in a DTD an element that contains
string data (i.e., #PCDATA) followed by a single element. It is my
understanding that the following is INCORRECT:
<!ELEMENT elem1 (#PCDATA, elem2)>
Is my understanding correct, i.e., that it is incorrect?
It is my understanding that this is the way to do it:
<!ELEMENT elem1 (#PCDATA | elem2)*>
However, this is not really what I wanted. This allows elem2 to come
before the #PCDATA (and it allows many other undesirable combinations).
Is there a way to specify that you want PCDATA followed by an element?
(3) Can you have an entity for an element, i.e.,
<!ENTITY conv "Conversation">
<&conv;>Oh, by the way, did you see ...</&conv;>