[tei-council] Crit App, XPointer Schemes

[James Cummings]

As part of http://purl.org/tei/bug/3497369 I'm tasked with 
drafting a new short section on linking methods for critical 
apparatus to become a new 12.2.4 section.  My draft so far looks 
like the below.  Before committing it, does anyone have any 
suggestions or corrections they would like to make?

-James


12.2.4

Linking methods

When an apparatus is provided it does not need to be given at the 
location in the transcription where the variation occurs. Instead 
it may be stored in a separate place in the same file, or indeed 
in another file, and point to the location at which it is meant 
to be used. Storing apparatus entries separately can be 
beneficial when encoding multiple competing, potentially 
overlapping, interpretations of the same variation in the source 
texts.

The location-referenced method can be used to point a position in 
a text using the @loc attribute and a canonical reference that is 
understood and documented in the context of the file where it is 
used. Where possible it is recommended that other methods use the 
@from attribute to point to an @xml:id attribute on an <anchor/> 
or other element at the location where the variation takes place. 
The contents of an element pointed to are understood to be 
equivalent to a <lem> if none exists in the <app>, and if a <lem> 
does exist this should replace any content.

The @from attribute is a data.pointer datatype and thus contains 
a URI as a value.  This means that it can point directly to an 
@xml:id, an @xml:id in another local file, or indeed a file 
identified by any URL or URN.

===

<l n="1"><seg xml:id="WBP-so.1.1">Experience</seg> though noon 
Auctoritee</l>

<!-- In another file -->

  <app from="wbp.xml#WBP-so.1.1>
   <rdg wit="#La">Experiment</rdg>
   <rdg wit="#Ra2">Eryment</rdg>
  </app>

===

This could also be encoded as:

===

<l n="1"><anchor xml:id="WBP-so.1.1a"/> though noon Auctoritee</l>

<!-- In another file -->

  <app from="http://www.example.com/wbp.xml#WBP-so.1.1a>
   <lem>Experience</lem>
   <rdg wit="#La">Experiment</rdg>
   <rdg wit="#Ra2">Eryment</rdg>
  </app>

===

However, this should be considered more fragile since a full 
reading of the <lem> is not provided in the source file.

In addition, URLs can contain XPointer schemes including 
xpath1(), range, and string-range() which can be used in 
providing the location of an <app> that is stored separately from 
the text to which it applies. Both @from and @to can be used, as 
in the double end-point attachment method, to identify the 
starting and ending location for an apparatus using XPointer 
schemes to more precisely identify this location where beneficial.

===

<l n="1" xml:id="WP.1a">Experience though noon Auctoritee</l>

<!-- In another file -->

  <app from="wbp.xml#string-range(WBP.1a, 0, 10)">
   <lem>Experience</lem>
   <rdg wit="#La">Experiment</rdg>
   <rdg wit="#Ra2">Eryment</rdg>
  </app>

===


If only the @from attribute is provided then it should be 
understood that this supplies the location of the textual 
variance that the apparatus documents.  If the @from attribute 
contains an XPointer scheme that identifies a range of text (or 
elements) then this is understood to record the starting and 
ending of the range as in the double end-point attachment method.





-- 
Dr James Cummings, InfoDev
Oxford University Computing Services
University of Oxford