XPath prequel for Edirom Summer School

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Basic knowledge of XPath is essential for TEI Publisher customisation.

This short introduction is intended to help understand expressions used through the TEI Publisher on-line course.

XML as a tree

<?xml version="1.0" encoding="UTF-8"?>
<div xmlns="http://my.fantasy.namespace">
    <!-- This whole document is in a made-up namespace -->
    <p>The story begins as two ducks (<name type="org" key="mallards">Mr. and Mrs. Mallard</name>)
        fly over various potential locations in <name type="place" key="new-england">New
            England</name> to start a family.</p>
</div>

Node types in XML document

• element
• attribute
• text
• namespace
• processing-instruction
• comment
• document node

Family relationships between nodes

• parent
• child
• ancestor
• descendant
• sibling
• self

child

parent

descendant

ancestor

XPath

XPath is a language for selecting sets of nodes

Main thing an XPath expression does is to describe, in a formal way that a computer can process easily, certain sets of nodes, e.g.:

• title of the document
• all first paragraphs in a section
• all references to a name of a person
• all sections that are not of type appendix

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TEI/XML document

Viewed in Text mode

Viewed in a Tree Editor

oXygen > Tools > Tree Editor

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Testing XPath expressions

eXide

http://localhost:8080/exist/eXide/index.html

namespace

To query TEI documents, you need to declare the TEI namespace

declare namespace tei="http://www.tei-c.org/ns/1.0";

context

specify the context with doc() or collection() functions, otherwise the entire database is searched

e.g. doc("/db/apps/tei-publisher/data/test/graves6.xml") or collection("/db/apps/tei-publisher/data/test")