Metadata mechanism

[Patrick Durusau <patrick@durusau.net>]

Greetings!

Adding a paragraph in the introduction that notes a general theme that 
metadata should use an element structure and not attributes. The issue 
comes up with collaborative editing, the same "metadata" from multiple 
authors but also enables user naming of metadata without requiring 
schema changes, as would be the case with attribute based metadata.

Should note at some point that element based metadata does not prevent 
hard coding metadata for some purposes in the schema, while using the 
same mechanism for custom extension of the metadata.

I have been thinking about how this would work for things like roundtrip 
mapping, security, etc., and I have yet to encounter a case that cannot 
be handled by element based metadata. For round-tripping it requires 
rethinking how to link the metadata to the element in question but I 
think the advantages of a single general mechanism to handle metadata 
that does not require changes to the schema no matter what metadata is 
in question is a net win.

Not to commit myself or anyone else on syntax but thinking along the lines:

<metadata> <!-- generic metadata container -->
<name></name>
<value></value>
<apply> <!-- point of application, if absent, applied to immediate 
ancestor in tree, always last element in metadata element, I avoided 
saying link as that implies a particular method of addressing -->
<metadata> <!-- recursive embedding of metadata element --> </metadata>
</metadata>

Thoughts? Comments?

Hope everyone is having a great day!

Patrick

-- 
Patrick Durusau
Patrick@Durusau.net
Chair, V1 - Text Processing: Office and Publishing Systems Interface
Co-Editor, ISO 13250, Topic Maps -- Reference Model
Member, Text Encoding Initiative Board of Directors, 2003-2005

Topic Maps: Human, not artificial, intelligence at work!