Namespaces and DTDs

• DTDs must declare the qualified names

  <!ELEMENT svg:text (#PCDATA)>

• If the prefix changes, the DTD needs to change too.

• Parameter entity references can help when the prefix changes or is removed:

  <!ENTITY % mathml-colon               ''>
  <!ENTITY % mathml-prefix              ''>
  
  <!ENTITY % mathml-exp                 '%mathml-prefix;%mathml-colon;exp' >
  <!ENTITY % mathml-abs                 '%mathml-prefix;%mathml-colon;abs' >
  <!ENTITY % mathml-arg                 '%mathml-prefix;%mathml-colon;arg' >
  <!ENTITY % mathml-real                '%mathml-prefix;%mathml-colon;real' >
  <!ENTITY % mathml-imaginary      '%mathml-prefix;%mathml-colon;imaginary' >
  

• DTDs need to declare the xmlns and xmlns:prefix attributes too:

  <!ATTLIST svg xmlns (CDATA) #FIXED "http://www.w3.org/2000/svg">

  <!ATTLIST svg:svg xmlns:svg (CDATA) #FIXED "http://www.w3.org/2000/svg">

  However, you should not rely on this. Always explicitly specify the namespace declaration in the instance documents.