Models and methodologies to represent

the digital text.

Introduction to TEI, methods and languages to data management and display

Tiziana Mancinelli

Scholarly Editing and the Media Shift – Procedures and Theory

Verona 8/9 settembre 2015

Aims of this workshop:

Textual Markup

In order to talk about texts, markup and encoding of texts, we need to understand what we mean by these basic concepts.

When we talk about text encoding, what do we mean by a text?

What is in a text and what assumptions do we make in reading them?

A text is not a document

- A ”document” is something that exists in the world, which we can digitize.

- A ”text” is an abstraction, created by or for a community of readers, which we can encode.

Text

Markup can assist in answering research questions, and the

deciding what markup is needed to enable such questions to

be answered can be a research activity in itself

Imagine you are going to markup several thousand pages of

complex material....

Which features are you going to markup?

Why are you choosing to markup this feature?

How reliably and consistently can you do this?

Now, imagine your budget has been halved.

XML is structured data represented as strings of text

XML looks like HTML, except that:-

XML is extensible

XML must be well-formed

XML can be validated

XML is application-, platform-, and vendor- independent

XML empowers the content provider and facilitates data

integration

It is one of the best plain text long-term preservation formats

for textual data that we have

You use XML almost every day, never mind the web but in

many devices or even derived analogue information sources

An XML document may contain:

- elements, possibly bearing attributes

- processing instructions

- comments

- entity references

- namespaces

An XML document must be well-formed and may be valid

<?xml version="1.0" ?>

  <root>

     <element attribute="value">I like encoding!</element>

<!-- this is a comment -->

  </root>

<?xml version="1.0" ?>

  <root>

     <element attribute="value">I like encoding!</element>

<!-- this is a comment -->

  </root>

- An XML document represents a (kind of) tree

- It has a single root and many nodes

- Each node can be a subtree a single element

(possibly bearing some attributes)

- a string of character data

- Each element has a name or generic identifier

- XML elements and attributes are case sensitive

- An XML document represents a (kind of) tree

- It has a single root and many nodes

- Each node can be a subtree a single element

(possibly bearing some attributes)

- a string of character data

- Each element has a name or generic identifier

- XML elements and attributes are case sensitive

- An XML document is encoded as a linear string of characters

It begins with a special processing instruction

- Element occurrences are marked by start and end-tags

- The characters < and & are Magic

and must always be ”escaped” using &lt; or &amp; if you want to use them as themselves

- Comments are delimited by

<!-- and -->

- Attribute name/value pairs are supplied on the start-tag and

may be given in any order

- Entity references are delimited by & and ;

- An XML document is encoded as a linear string of characters

It begins with a special processing instruction

- Element occurrences are marked by start and end-tags

- The characters < and & are Magic

and must always be ”escaped” using &lt; or &amp; if you want to use them as themselves

- Comments are delimited by

<!-- and -->

- Attribute name/value pairs are supplied on the start-tag and

may be given in any order

- Entity references are delimited by & and ;

• The XML declaration
• Namespace declarations
• The root element of the document itself
• Other elements and content
• Attribute and value

<?xml version="1.0"?>

<greetings xmlns="http://www.example.org/greetings">

    <hello type="ironic">hello world!</hello>

</greetings>

An XML document must begin with an XML declaration

which does three things:

- specifies that this is an XML document

- specifies which version of the XML standard it follows

- specifies which character encoding the document uses

<?xml version="1.0"?>

<?xml version="1.0" encoding="iso-8859-1" ?>

An XML document must begin with an XML declaration

which does three things:

- specifies that this is an XML document

- specifies which version of the XML standard it follows

- specifies which character encoding the document uses

<?xml version="1.0"?>

<?xml version="1.0" encoding="iso-8859-1" ?>

All TEI documents are declared within the TEI namespace:

<TEI xmlns="http://www.tei-c.org/ns/1.0"> ...

</TEI> XML documents can include elements declared in different

name spaces.

- a namespace declaration associates a namespace prefix with

an external URI-like identifier the default namespace may be declared using a xmlns other name spaces must all use a specially declared prefix

<TEI xmlns="http://www.tei-c.org/ns/1.0" xmlns:math="http://www.mathml.org">

<p>...<math:expr>...</math:expr>...</p>...</TEI>

The xml namespace is used by the TEI for global attributes

@xml:id and @xml:lang

An XML Schema is a language for expressing constraints about XML documents. There are several different schema languages in widespread use, but the main ones are Document Type Definitions (DTDs), Relax-NG, Schematron and W3C XSD (XML Schema Definitions).

XML

XML - SCHEMA

The Text Encoding Initiative Consortium is an international organization whose mission is to develop and maintain guidelines for the digital encoding of literary and linguistic texts. The Consortium publishes the Text Encoding Initiative Guidelines for Electronic Text Encoding and Interchange: an international and interdisciplinary standard that is widely used by libraries, museums, publishers, and individual scholars to represent all kinds of textual material for online research and teaching.

Guidelines

Tools

<TEI>

<TeiHeader>

<text>

<body>

<head>

<lg>

<opener>

<l>

<l>

<l>

<p>

XML syntax: the small print

What does it mean to be well-formed

There is a single root node containing the whole of an XML

document

Each subtree is properly nested within the root node

Element/attribute/etc. names are always case sensitive

Start-tags and end-tags are always mandatory except there

can be combined start-and-end tags for certain elements:

The TEI is not (just) a schema!

It is:

an international consortium supported by libraries and universities with stable large open source community a set of definitions, examples and discussion of several hundred useful and mostly textual distinctions a set of regularly maintained and updated recommendations:

’The TEI Guidelines’ a set of customizable tools and stylesheets for transformations to/from many formats (e.g. HTML, Word, PDF, Databases, RDF/Linked Data, Slides, ePub, Schemas, etc.) an archivally well-understood, consensus-based way of organizing and structuring textual (and other) resources an evolving history of the concerns of the digital humanities community whatever you make it... it is a community-developed standard.