Syd: initial creation of clever but insufficient test for duplicate witness references in an

2016-01-10T19:39:54Z

initial creation of clever but insufficient test for duplicate witness references in an <app>

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In general, a given witness should only be referred to once within an
<code><app></code> (either on the <code>@wit</code> of
<code><rdg></code> or of <code><lem></code>).

This snippet of ODD code may be included in the
<code><elementSpec></code> for <tt>app</tt> to test the collection
of pointers to witnesses within a given <code><app></code> for
duplicates.

This test is insufficient for a variety of reasons. First,
the ''TEI Guidelines'' explicit permit the specification of witnesses (on
<code>@wit</code>) for one reading to be omitted. (See
[http://www.tei-c.org/release/doc/tei-p5-doc/en/html/TC.html#TCAPPS 12.2.3 The Parallel Segmentation Method].)

Second, this code only tests the string value of a given pointer, not
what it points at. Thus the value of <code>@xml:base</code> is not
taken into account, and the values <code>"witnesses.xml#A"</code>
& <code>"./witnesses.xml#A"</code> will incorrectly be considered
as different. Similarly, this code will consider it OK when two
<code>@wit</code> pointers point two two different
<code>witness</code> elements that list the same MSS. (Arguably bad
encoding, but not technically incorrect.)

This also means that a repeated pointer to a witness (also bad
encoding, but not technically incorrect) will be flagged as an error.

And, perhaps most importantly, it means that this test does not check
that the pointers on <code>@wit</code> actually point to
<code>witness</code>es, as opposed to, say, <code>person</code>s.

<pre><nowiki><constraintSpec ident="unique-witness-within-app" scheme="isoschematron">
<constraint>
<sch:let name="wits" value="tokenize( normalize-space( string-join( .//@wit,' ') ),' ')"/>
<sch:let name="witless" value="distinct-values( $wits )"/>
<sch:report test="count( $wits ) ne count( $witless )">Duplicate witness within 'app'</sch:report>
</constraint>
</constraintSpec></nowiki></pre>

[[Category:Customization]]

[[Category:Schematron]]

Unique-witnesses-within-app - Revision history

Syd: initial creation of clever but insufficient test for duplicate witness references in an