Including shared parts of XML converters

AnnoCultor provides a way to reuse common parts of converters at XML level. The shared part is separated in an XML file (without headers) that is then literally included into the converter.

Creating the common block

Just cut the common part of a converter in XML, and save it in a separate file, giving it extension .xml.

Let us call it common.xml and place it one level above the converter itself.

Linking to the common block

Add an XML entity pointing to the common XML file:

 <!DOCTYPE rdf:RDF [
        ...
                
    <!ENTITY common SYSTEM '/../common.xml'> 
    
]>

Using the common block

Use XML entity expansion to (literally) include the common file into a converter. In our example, placing &common; somewhere in the converter would literally replace &common; with the contents of this file.

Resolving common blocks

The entities are resolved against the profile directory. However, your operating system will try to resolve the filename, as provided in the XML file.

To include a file from the profile directory we need to prevent this resolution by artificially moving up-down in file path. For example, imagine that profiles are stored in directory profile where we want to put our common.xml The following fragment should do it:

 <!DOCTYPE rdf:RDF [
        ...
                
    <!ENTITY common SYSTEM '/../profile/common.xml'> 
    
]>