Subject: Re: [docbook-apps] Re: SGML to XML: Should I switch? How to switch?
Bruce D'Arcus wrote: > On 7/17/05, Mauritz Jeanson <firstname.lastname@example.org> wrote: >>> -----Original Message----- >>> From: Thomas Schraitle > > [... snip ...] > >>> I think, that's not the whole story: XML needs a public _and_ >>> a system identifier in the DOCTYPE declaration. >> Just a small clarification: a valid XML document must have a system >> identifier. It may also have a public identifier, but that is not required. > > Actually, a valid xml document doesn't need a doctype declaration at > all. I never use them in my documents. > No and no. A valid XML document MUST have a DOCTYPE declaration. A merely well-formed document does not need one, but it is required for validity. In order for a document to be valid the document type declaration must contain either a system identifier pointing to an external DTD subset or an internal DTD subset or both. A valid document may but does not have to have a public identifier. However XML does not allow public identifiers without system identifiers in DOCTYPE declarations. Even if you use the PUBLIC keyword, you most provide both a public ID and a system ID. -- Elliotte Rusty Harold email@example.com XML in a Nutshell 3rd Edition Just Published! http://www.cafeconleche.org/books/xian3/ http://www.amazon.com/exec/obidos/ISBN=0596007647/cafeaulaitA/ref=nosim