Can you ensure an element is not empty in the DTD?

[dman]

<!DOCTYPE transactions [
<!ELEMENT transactions (transaction)*>
<!ELEMENT transaction (date, merchant, cardtype, amount)>
<!ELEMENT date (#PCDATA)>
<!ELEMENT merchant (#PCDATA)>
<!ELEMENT cardtype (#PCDATA)>
<!ELEMENT amount (#PCDATA)>
]>
Suppose I have something like above. Is there a way to ensure that
when the xml is validated, that every tag has some text in it through
the DTD? Or does that need to be done at the application level?

Thanks for your help.

Dennis

 

[Joseph Kesselman]

Not in DTDs. Schemas can enforce a minimum data length.