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This chapter describes the overall structure of the encoding scheme defined by these Guidelines. It introduces the conceptual framework within which the following chapters are to be understood, and describes the technical means by which that conceptual framework is implemented in SGML. It assumes some familiarity with SGML; see chapter 2 .
The TEI encoding scheme consists of number of modules or DTD fragments which we refer to below as tag sets. Selected tag sets may be combined in many different ways, according to principles described in this chapter, within the framework of the TEI main DTD. Auxiliary tag sets are also defined for specific purposes independent of the TEI main DTD.
The DTD fragments from which the main TEI DTD is constructed may be classified as follows:
The first two sections of this chapter discuss these distinctions and list the specific tag sets included in each category. Section 3.3 describes how to invoke the TEI document type declaration, and how to specify which of the various base tag sets and optional additional tag sets are used in a document.
The global attributes, characteristics postulated of every element or tag in the encoding scheme, are defined in section 3.5 .
The remainder of the chapter contains a more technical description of the SGML mechanisms used to implement the encoding scheme. It may be skipped at a first reading, but a proper understanding of the topics addressed here is essential for anyone planning to modify or extend the TEI encoding scheme in any way (see also chapter 29 ), and also highly desirable for those wishing to take full advantage of its modular nature. The structure of the main TEI DTD file itself is outlined in section 3.6 . The element classes used to define smaller groups of elements and their characteristics are described in section 3.7 . Both global attributes and element classes are implemented using SGML parameter entities; various other uses of parameter entities in the TEI DTDs are discussed in section 3.8 .
These Guidelines define a large number of SGML tags for marking up documents, all of which are formally defined within the document type declaration (DTD) files provided by the TEI and documented in the remainder of the present document. The tags are grouped into tag sets or DTD fragments, each comprising a set of declarations for tags which belong together in some respect, typically related to their intended application area.
All tags used to transcribe documents are available for use within the main DTD of the TEI and are defined in Parts III and IV of these Guidelines. There are DTD fragments for prose and mixed matter, verse and verse collections, drama, dictionaries, analysis and interpretation of text, text criticism, etc. A full list, including the files in which they are defined, and the rules determining their selection and combination, is given in section 3.2 .
A number of auxiliary DTDs are also defined in these Guidelines. These are used for the encoding of ancillary descriptive information useful when processing electronic documents. Part V of these Guidelines describes several such auxiliary document types, specifically:
An independent header typically describes the encoding of a specific document, but in the case of a planned corpus or collection, it may define a set of encoding practices common to all texts in the collection. The other auxiliary document types provide information likely to be relevant to many documents, rather than to individual documents.
When individual TEI documents are exchanged between sites, they should be accompanied by whatever auxiliary documents apply to them. When larger groups of documents are exchanged, the relevant auxiliary documents need be exchanged only once. For further information see chapter 30 .
The DTD files containing these auxiliary DTDs are:
Some of these auxiliary DTDs also make use of the core tag set defined as part of the main TEI DTD; this is described in the relevant chapters of part V.
The main TEI DTD is constructed by selecting an appropriate combination of smaller tag sets, each containing some set of tags likely to be used together. These building blocks include:
The interpretation of the parameter entity declarations, and the inclusion of the appropriate tag sets, are handled by a single `driver file' for the main TEI DTD. This file, tei2.dtd , is described in detail below in section 3.6 . The remainder of the present section identifies the files in which each tag set is contained, and the parameter entities associated with them.
Two `core' tag sets are always included in every invocation of the main TEI DTD. The tags and attributes that they contain are therefore available to any TEI document. The parameter entities used for this purpose, and the files they refer to, are:
The base tag sets are those which define the basic building blocks of different text types. The basic structures of verse (line, stanza, canto, etc.), for example, are not those of prose (paragraph, section, chapter, etc.), while dictionaries use yet another set of basic structures. Each base corresponds to one chapter of Part III of this document.
In general, exactly one base tag set must be selected for any TEI-conformant document. Errors will result if none, or more than one, is selected, because the same elements may be differently defined in different base tag sets. For documents which mingle structurally dissimilar elements and require elements from more than one base, however, either the mixed base or the general base may be used; see section 3.4 . These bases require the encoder to specify which of the other bases are to be combined.
The encoder selects a base tag set by declaring the appropriate SGML parameter entity with the replacement text INCLUDE . To invoke the base tag set for prose, for example, the encoder must ensure that the DTD subset in the document contains the declaration:
<!ENTITY % TEI.prose 'INCLUDE' >
The entities used to select the different base tag sets, and the files containing the SGML declarations for each base, are listed below.
As shown in the list, each base tag set is normally contained in one or two system files: a required one (with the extension `dtd') defining the elements in the tag set and their attributes, and an optional one (with the file extension `ent') defining any global attributes or specialized element classes enabled by that tag set. The parameter entities for these files have the same name as the enabling parameter entity for the base, with the suffixes `ent' and `dtd' respectively: the prose base, for example, is enabled by declaring the parameter entity TEI.prose as INCLUDE ; this in turn enables declarations of TEI.prose.ent and TEI.prose.dtd as the system files teipros2.ent and teipros2.dtd . For further details, see section 3.6 .
Most base tag sets (but not necessarily all) embed common definitions of text structure, front matter, and back matter, by referring to three standard parameter entities; these are:
The additional tag sets define optional tags required by different encoders for different types of analysis and processing; each corresponds to a chapter in part IV of this document. In any TEI encoding, any or all of these additional tag sets may be made available, as they are all compatible with each other and with every base tag set. They are invoked in the same way as base tag sets, by defining the appropriate parameter entity as INCLUDE ; the relevant parameter entities, and the files containing the additional tag sets, are these:
Like the base tag sets, the additional tag sets are each contained in one or two system files: a required one (with the file extension `dtd') defining the elements in the tag set and their attributes, and an optional one (with the file extension `ent') defining any global attributes or specialized element classes enabled by that tag set. The parameter entities for these files have the same name as the enabling parameter entity for the tag set, with the suffixes `ent' and `dtd' respectively: the additional tag set for linking, segmentation, and alignment, for example, is enabled by declaring the parameter entity TEI.linking as INCLUDE ; this in turn enables declarations of TEI.linking.ent and TEI.linking.dtd as the system files teilink2.ent and teilink2.dtd .
As described in chapter 29 , users may modify the markup language defined here by renaming elements, suppressing elements, adding new elements, or modifying element or attribute-list declarations. In general, local modifications will be most conveniently grouped into two files: one containing the local modifications to parameter entities used in the DTDs, and the other containing new or modified declarations of elements and their attributes. These files will be embedded in the TEI DTD if they are associated with the following two parameter entities:
In some cases, users may wish to provide completely new base or additional tag sets, to be invoked in the same way as those defined in this document; such tag sets should also be divided into `entity files' and `DTD files' in the same way as the standard tag sets. Such modifications should be undertaken only with a thorough understanding of the interface among core, base, and additional tag sets as documented in the final sections of this chapter; see in particular section 3.6.2 .
Further recommendations for the creation of user-defined extension or modification are provided in chapters 29 and 28 .
Like any other SGML document, a TEI document must begin with a document type definition (DTD). Local systems may allow the DTD to be implicit, but for interchange purposes it must be explicit. Because of its highly modular nature, it may in any case be desirable for the component parts of the TEI DTD to be made explicit even for local processing.
The simplest version of the TEI DTD names the main TEI DTD file as an external file, and specifies a single base tag set for use in the document, using the parameter entity names specified in section 3.2 . For example, a document using the base tag set for prose will begin with a document type declaration something like this:
<!DOCTYPE TEI.2 PUBLIC "-//TEI P3//DTD Main Document Type//EN"
"tei2.dtd" [
<!ENTITY % TEI.prose 'INCLUDE' >
]>
A document using the base tag set for drama will define a different
parameter entity:
<!DOCTYPE TEI.2 PUBLIC "-//TEI P3//DTD Main Document Type//EN"
"tei2.dtd" [
<!ENTITY % TEI.drama 'INCLUDE' >
]>
If one or more of the additional tag sets described in Part IV are to be used, they are invoked in the same way as the base tag set. A document using the base tag set for prose, with the additional tag sets for text criticism and for linking, segmentation, and alignment, for example, will begin with a document type declaration something like this:
<!DOCTYPE TEI.2 PUBLIC "-//TEI P3//DTD Main Document Type//EN"
"tei2.dtd" [
<!-- TEI base tag set specified here: ... -->
<!ENTITY % TEI.prose 'INCLUDE' >
<!-- TEI additional tag sets optionally specified here: ... -->
<!ENTITY % TEI.textcrit 'INCLUDE' >
<!ENTITY % TEI.linking 'INCLUDE' >
]>
If local modifications are used, they may be stored in separate files and pointed to using the parameter entities TEI.extensions.ent and TEI.extensions.dtd . If such local modifications are added to the example just given, this is the result:
<!DOCTYPE TEI.2 PUBLIC "-//TEI P3//DTD Main Document Type//EN"
"tei2.dtd" [
<!-- Local modifications to the TEI DTD declared here. They
will be embedded at an appropriate point in the main
DTD. ... -->
<!ENTITY % TEI.extensions.ent system 'project.ent' >
<!ENTITY % TEI.extensions.dtd system 'project.dtd' >
<!-- TEI base tag set specified here: ... -->
<!ENTITY % TEI.prose 'INCLUDE' >
<!-- TEI additional tag sets specified here: ... -->
<!ENTITY % TEI.textcrit 'INCLUDE' >
<!ENTITY % TEI.linking 'INCLUDE' >
]>
If the document requires tags which are defined in different base tag sets (e.g. prose and drama) or embeds smaller texts which use different base tag sets, then one of the mixed-type bases must be used. Their proper invocation is described below in section 3.4 .
The TEI DTD has been designed to simplify the task of choosing an appropriate set of tags for the text in hand. The core tag set includes tags appropriate to the majority of simple tagging requirements for prose, verse and drama, irrespective of the base tag set chosen. For more detailed tagging, the encoder may choose the prose base for prose texts, the verse base for verse, and so on.
In discussing these base tag sets elsewhere in these Guidelines, it is generally assumed for clarity of exposition that a text will fall into one, not several, of these types. It is not uncommon, however, for a text to combine prose and verse, or other forms treated by the TEI as different bases. Examples include:
The TEI DTD provides the following mechanisms to handle these cases:
Whichever mechanism is adopted, if the whole of the resulting document is to be parseable by the main TEI DTD it may need to combine elements from different TEI base tag sets. Two special-purpose base tag sets are defined for this purpose:
When either of these `combined' bases is used, the user must specify all of the other bases to be included in the mix as well as either the general or the mixed base. This is the only exception to the general rule that no more than one base tag set may be enabled in a TEI document. The following set of declarations for example allows for any mixture of the low level structural tags defined in the prose, drama and dictionary base tag sets:
<!DOCTYPE TEI.2 PUBLIC "-//TEI P3//DTD Main Document Type//EN"
"tei2.dtd" [
<!ENTITY % TEI.mixed 'INCLUDE' >
<!ENTITY % TEI.prose 'INCLUDE' >
<!ENTITY % TEI.drama 'INCLUDE' >
<!ENTITY % TEI.dictionaries 'INCLUDE' >
<!-- Structurally, Moby Dick is not your
everyday common or garden variety novel ... -->
]>
The following set of declarations has the same effect, but with the
additional restriction that each text division (i.e. each member of the
element class divn ) must be homogenous with
respect to the mixture of available bases. Because in a
`general' base, each <div> of the text may use
a different base, the divisions of the text prefixed by this set of
declarations will each be composed of elements taken solely from one of
the prose, verse or dictionary base tag sets:
<!DOCTYPE TEI.2 PUBLIC "-//TEI P3//DTD Main Document Type//EN"
"tei2.dtd" [
<!ENTITY % TEI.general 'INCLUDE' >
<!ENTITY % TEI.prose 'INCLUDE' >
<!ENTITY % TEI.drama 'INCLUDE' >
<!ENTITY % TEI.dictionaries 'INCLUDE' >
]>
The actual DTD fragments for the combined bases do nothing but embed the default tag set for overall text structure. The mixed-base tag set is in file teimix2.dtd :
<!-- 3.4: Mixed-Base Tag Set --> <!-- Text Encoding Initiative: Guidelines for Electronic --> <!-- Text Encoding and Interchange. Document TEI P3, 1994. --> <!-- Copyright (c) 1994 ACH, ACL, ALLC. Permission to copy --> <!-- in any form is granted, provided this notice is --> <!-- included in all copies. --> <!-- These materials may not be altered; modifications to --> <!-- these DTDs should be performed as specified in the --> <!-- Guidelines in chapter "Modifying the TEI DTD." --> <!-- These materials subject to revision. Current versions --> <!-- are available from the Text Encoding Initiative. --> <!ENTITY % TEI.structure.dtd system 'teistr2.dtd' > %TEI.structure.dtd;The general-base tag set is in file teigen2.dtd :
<!-- 3.4: General-Base Tag Set --> <!-- Text Encoding Initiative: Guidelines for Electronic --> <!-- Text Encoding and Interchange. Document TEI P3, 1994. --> <!-- Copyright (c) 1994 ACH, ACL, ALLC. Permission to copy --> <!-- in any form is granted, provided this notice is --> <!-- included in all copies. --> <!-- These materials may not be altered; modifications to --> <!-- these DTDs should be performed as specified in the --> <!-- Guidelines in chapter "Modifying the TEI DTD." --> <!-- These materials subject to revision. Current versions --> <!-- are available from the Text Encoding Initiative. --> <!ENTITY % TEI.structure.dtd system 'teistr2.dtd' > %TEI.structure.dtd;
The following attributes are defined for every TEI element. [ see note 18 ]
Some tag sets (e.g. those for terminology, linking, and analysis) define other global attributes; these are documented in the appropriate chapters of Part III and Part IV. See also section 3.7.1 .
An additional attribute, TEIform , is also defined for every TEI element. Unlike the other attributes defined for every element, TEIform is not defined by class global because its default value is different in every case and must be defined individually for each element. [ see note 19 ]
Any TEI element may be given values for id , n , lang , rend , or TEIform , simply by specifying values for these attributes. The following two examples convey the same information about the text: that the material transcribed occurs within a <p> element (paragraph). They differ only in that the second provides an identifier for the paragraph, to which other elements (e.g. notes or hypertext links) can conveniently refer.
<p>If to do were as easy as to know what were good to do, chapels had been churches and poor men's cottages princes' palaces. It is a good divine that follows his own instructions ...</p>
<p id='MV1.2.5'>If to do were as easy as to know what were good to do, chapels had been churches and poor men's cottages princes' palaces. It is a good divine that follows his own instructions ...</p>
ID values must be legal SGML names; by default, this means they must begin with a letter from A to Z or a to z and contain no characters other than the letters A to Z or a to z, the digits 0 to 9, the full stop, and the hyphen. Furthermore, by default upper and lower case letters are not distinguished: thus, the strings `a23' and `A23' are identical, and may not be used to identify two distinct elements. If two elements are given the same identifier, the SGML parser will signal a syntax error. The following example, therefore, is not valid:
<p id=page1><q>What's it going to be then, eh?</q></p> <p id=page1>There was me, that is Alex, and my three droogs, that is Pete, Georgie, and Dim, ... </p>
For a discussion of methods of providing unique identifiers for elements, see section 6.9.2 .
The n attribute allows identifying information (e.g. chapter numbers, etc.) to be encoded even if it would not be a legal id value. Its value may be any string of characters; typically it is a number or other similar enumerator or label. For example, the numbers given to the items of a numbered list may be recorded with the n attribute; this would make it possible to record errors in the numeration of the original, as in this list of chapters, transcribed from a faulty original in which the number 10 is used twice, and 11 is omitted:
<list type=ordered> <item n=1>About These Guidelines <item n=2>A Gentle Introduction to SGML <!-- ... --> <item n=9>Verse <item n=10>Drama <item n=10>Spoken Materials <!-- sic: original has '10' twice! --> <item n=12>Printed Dictionaries <!-- ... --> </list>The n attribute may also be used to record non-unique names associated with elements in a text, possibly together with a unique identifier as in the following examples:
<div type=chap n='One' id='TXT0101'>
<div type=stanza n='xlii'>
The lang attribute indicates the language, writing system, and character set associated with a given element and all its contents. If it is not specified, the value is inherited from that of the immediately enclosing element. As a rule, therefore, it is simplest to specify the base language of the text on the <tei.2> element, and allow most elements to take the default value for lang ; the language of an element then need be explicitly specified only for elements in languages other than the base language.
The following two encodings convey the same information about the language of the text, since in the first the lang attributes on the <emph> elements specify the same value as that on the parent <p> element, while in the second they inherit that value without specifying it.
<p lang=en> ... Both parties deprecated war, but one of them would <emph lang=en>make</emph> war rather than let the nation survive, and the other would <emph lang=en>accept </emph> war rather than let it perish, and the war came.</p>
<p lang=en> ... Both parties deprecated war, but one of them would <emph>make</emph> war rather than let the nation survive, and the other would <emph>accept</emph> war rather than let it perish, and the war came.</p>
In the following example, by contrast, the lang attribute on the <term> element must be given if we wish to record the fact that the technical terms used are Latin rather than English; no lang attribute is needed on the <q> element, by contrast, because it is in the same language as its parent. It is strongly recommended that all language shifts in the source be explicitly identified by use of the lang attribute, as described in chapter 4 .
<p lang=en>The constitution declares <q>that no bill of attainder or <term lang=la>ex post facto</term> law shall be passed.</q> ... </p>
Formally, the lang attribute is an IDREF ; a reference to the id value of a <language> element in the TEI header. [ see note 20 ] This means that each language used in the document should be declared in the TEI header using the <language> element defined in section 5.4.2 .
The rend attribute is used to give information about the physical presentation of the text in the source. In the following example, it is used to indicate that both the emphasized word and the proper name are printed in italics:
<p> ... Their motives <emph rend='italics'>might</emph> be pure and pious; but he was equally alarmed by his knowledge of the ambitious <name rend='italics'>Bohemond</name>, and his ignorance of the Transalpine chiefs: ...</p>If all or most <emph> and <name> elements are rendered in the text by italics, it will be more convenient to register that fact in the TEI header once and for all and specify a rend value only for any elements which deviate from the usual rendition.
The contents of the rend attribute are free text. In any given project, encoders are advised to settle on a standard vocabulary with which to describe typographic or manuscript rendition of the text, and to document their usage of that vocabulary in the <rendition> element of the TEI header.
The TEIform attribute is used to allow application programs to handle TEI-encoded documents correctly even if some or all elements have been renamed. Most users can ignore this attribute entirely; it is only relevant when the TEI DTDs are modified. [ see note 21 ]
The default value of TEIform for any element is the generic identifier of that element, as described in this document. The value for <p> is `p', the value for <div1> is `div1', etc. When elements are renamed, as described in chapter 29 , the declaration of TEIform is not modified. If <div1> is renamed <chapter> , for example, the default value of TEIform remains `div1'. An application program which does not recognize the new generic identifier can check to see whether the attribute TEIform exists, and examine its value if it does to find out which TEI element, if any, is being used.
Modifications of DTDs, however, may involve more than simple renaming of elements: sometimes elements are given not just new names, but complete new definitions. In such cases, the TEIform attribute may be used to indicate the standard TEI element corresponding to the modified element. For example, if a local modification of a DTD renamed the <div1> element as <chapter> and also modified its formal declarations (e.g. to change its content model), then the TEIform attribute on the modified element should be given the default value div1 , in order to indicate that the local <chapter> element is a modification of the standard TEI <div1> .
When new elements are introduced, they may be identified as specialized variants of existing TEI elements by giving them the appropriate default value for TEIform . For example, if a local element called <quatrain> were introduced, as a specialized variant of the <lg> (line group) element which must contain exactly four lines, then its declaration might give its TEIform as lg , to signify that a quatrain is a particular type of line group, thus:
<!ELEMENT quatrain - O (l, l, l, l) >
<!ATTLIST quatrain %a.global
TEIform (lg) 'lg' >
The formal definition of the global attributes is as follows:
<!-- 3.5: Global attributes -->
<!-- The global attributes are defined for every element in -->
<!-- the TEI tag set; individual declarations may be -->
<!-- overridden by local declarations for individual -->
<!-- elements. -->
<!-- If the tag sets invoked by the user define extra global -->
<!-- attributes (they do this in their .ent file), then they -->
<!-- are inherited by GLOBAL; otherwise the parameter -->
<!-- entities referred to expand to the empty string, as -->
<!-- shown here. -->
<!ENTITY % a.analysis '' >
<!ENTITY % a.linking '' >
<!ENTITY % a.terminology '' >
<!ENTITY % a.global ' %a.analysis;
%a.linking;
%a.terminology;
id ID #IMPLIED
lang IDREF %INHERITED
rend CDATA #IMPLIED
n CDATA #IMPLIED' >
<!-- The TEIform attribute is also global, but is declared -->
<!-- individually for each element, not in a parameter -->
<!-- entity declaration. -->
<!-- This fragment is used in sec. 3.7.3 -->
All TEI-encoded documents use the same top-level DTD file, which refers to a number of other DTD files, the exact set of other files referred to depending on which base and which additional tagsets are in use. The remainder of this chapter describes in some detail the organization and function of this file and those it embeds; it is necessarily of a rather technical and specialized nature.
The main TEI DTD is always invoked by specifying the file tei2.dtd . This file:
Each parameter entity associated with a tag set controls several marked sections in the main DTD file tei2.dtd . If the entity has been declared in the DTD subset with the text INCLUDE , then the marked sections it controls will be parsed; otherwise, they will be ignored. The marked sections controlled by each entity:
The tei2.dtd file has the following structure:
<!-- 3.6.1: File tei2.dtd: Main document type declaration --> <!-- file --> <!-- Text Encoding Initiative: Guidelines for Electronic --> <!-- Text Encoding and Interchange. Document TEI P3, 1994. --> <!-- Copyright (c) 1994 ACH, ACL, ALLC. Permission to copy --> <!-- in any form is granted, provided this notice is --> <!-- included in all copies. --> <!-- These materials may not be altered; modifications to --> <!-- these DTDs should be performed as specified in the --> <!-- Guidelines in chapter "Modifying the TEI DTD." --> <!-- These materials subject to revision. Current versions --> <!-- are available from the Text Encoding Initiative. --> <!-- This file first defines some useful entities, then --> <!-- defines the element TEI.2 and includes files with the --> <!-- various specialized parts of the document type --> <!-- declaration. It also declares the top-level TEI.2 and --> <!-- TEI.2.corpus elements. --> <!-- I. Preliminaries. --> <!-- Embed any local modifications to TEI entities. --> <!-- ... declarations from section 3.6.2 --> <!-- (Local modifications to parameter entities) --> <!-- go here ... --> <!-- Embed entities for TEI generic identifiers. --> <!ENTITY % TEI.elementNames system 'teigis2.ent' > %TEI.elementNames; <!-- Define entities for TEI keywords. --> <!-- This includes defining the default for each base and --> <!-- additional tag set as 'IGNORE'. --> <!-- ... declarations from section 3.8.3 --> <!-- (TEI Keywords) --> <!-- go here ... --> <!-- II. Define element classes for content models, shared --> <!-- attributes for element classes, and global attributes. --> <!-- (This all happens within the file TEIclas2.ent.) --> <!ENTITY % TEI.elementClasses system 'teiclas2.ent' > %TEI.elementClasses; <!-- III. Define the top-level TEI elements: one for --> <!-- individual texts, one for composites with a collective --> <!-- header. --> <!-- A TEI document is a text preceded by a TEI header. --> <!ELEMENT TEI.2 - O (teiHeader, text) > <!ATTLIST TEI.2 %a.global; > <!-- A TEI corpus is a series of TEI.2 documents, preceded --> <!-- by a corpus-level TEI header. --> <!ELEMENT teiCorpus.2 - O (teiHeader, TEI.2+) > <!ATTLIST teiCorpus.2 %a.global; > <!-- IV. Embed the actual tag sets. First embed any local --> <!-- modifications and extensions. Then embed the core tag --> <!-- sets, the (single) base tag set, and the (optional) --> <!-- additional tag sets specified by the user. --> <!-- ... declarations from section 3.6.2 --> <!-- (Embed local element declarations, etc.) --> <!-- go here ... --> <!-- ... declarations from section 3.6.3 --> <!-- (Embed the core tag sets) --> <!-- go here ... --> <!-- ... declarations from section 3.6.4 --> <!-- (Embed base tag set) --> <!-- go here ... --> <!-- ... declarations from section 3.6.5 --> <!-- (Embed additional tag sets) --> <!-- go here ... -->
A TEI-conformant document must use the tei2.dtd file, or one derived from it in the manner described in chapter 29 . It must also specify which base and which additional tag sets are to be invoked, using the mechanisms described in section 3.3 .
As noted above in section 3.2.4 , local modifications to the DTD are most conveniently grouped into two files, one containing modifications to the TEI parameter entities, and the other new or changed declarations of elements and their attributes. These files should be associated with the parameter entities TEI.extensions.ent and TEI.extensions.dtd by declarations included in the document's DTD subset.
For example, if the relevant files are called project.ent and project.dtd , then declarations like the following would be appropriate:
<!ENTITY % TEI.extensions.ent SYSTEM 'project.ent' > <!ENTITY % TEI.extensions.dtd SYSTEM 'project.dtd' >
When an SGML entity is declared more than once, the first declaration is binding and the others are ignored. The local modifications to parameter entities should therefore be handled before the standard parameter entities themselves are declared in tei2.dtd . The entity TEI.extensions.ent is referred to before any TEI declarations are handled, to allow the user's declarations to take priority. If the user does not provide a TEI.extensions.ent entity, the entity will be expanded to the empty string.
For example the encoder might wish to add two phrase-level elements <it> and <bd> , perhaps as synonyms for <hi rend='italics'> and <hi rend='bold'> . As described in chapter 29 , this involves two distinct steps: one to define the new elements, and the other to ensure that they are placed into the TEI document structure at the right place. We deal with the second first, by specifying the element class to which the new elements should be attached. To do this, the standard parameter entity x.phrase should be modified to include the two new generic identifiers. The file containing local declarations of the standard parameter entities will thus contain a declaration of the following form:
<!ENTITY % x.phrase 'it | bd |' >
The relevant fragment of the DTD is this:
<!-- 3.6.2: Local modifications to parameter entities --> <!-- Embed local modifications to TEI parameter entities. --> <!-- Declare entity as empty string first, in case user has --> <!-- no mods and has not declared it. --> <!ENTITY % TEI.extensions.ent '' > %TEI.extensions.ent; <!-- This fragment is used in sec. 3.6.1 -->
The second type of modification needed is most conveniently performed after all the standard TEI parameter entities have been declared; this allows the element declarations provided by the user to make use of the parameter entities which define standard TEI content models and attribute definitions. To facilitate this, the parameter entity TEI.extensions.dtd is used to embed local element declarations before any of the TEI tag sets are embedded by the file tei2.dtd , but after all the TEI element classes and other parameter entities have been declared.
The task of declaring the non-standard <it> and <bd> elements is thus simplified: they can, for example, use the same parameter entities as the <hi> element. A suitable local DTD-modifications file might look like the following (note that the standard parameter-entity reference for phrase sequence is used):
<!ELEMENT it - - (%phrase.seq) >
<!ATTLIST it
id ID #IMPLIED
lang IDREF %INHERITED
n CDATA #IMPLIED
rend CDATA #FIXED 'italics' >
<!ELEMENT bd - - (%phrase.seq) >
<!ATTLIST bd
id ID #IMPLIED
lang IDREF %INHERITED
n CDATA #IMPLIED
rend CDATA #FIXED 'boldface' >
For further examples of local modifications to both parameter entities and element declarations, see chapter 29 .
The relevant fragment of the DTD is this:
<!-- 3.6.2: Embed local element declarations, etc. --> <!-- Embedding local modifications here allows user --> <!-- modifications to use all the standard TEI element --> <!-- classes and parameter entities. --> <!ENTITY % TEI.extensions.dtd '' > %TEI.extensions.dtd; <!-- This fragment is used in sec. 3.6.1 -->
The core tag sets are embedded by the file tei2.dtd using the parameter entities TEI.header and TEI.core . The relevant fragment of the DTD is this:
<!-- 3.6.3: Embed the core tag sets --> <!-- These occur in all documents and are therefore defined --> <!-- unconditionally. --> <!ENTITY % TEI.header.dtd system 'teihdr2.dtd' > %TEI.header.dtd; <!ENTITY % TEI.core.dtd system 'teicore2.dtd' > %TEI.core.dtd; <!-- This fragment is used in sec. 3.6.1 -->
The default text structure tags, which are also documented as part of the core, are embedded by the base tag set, unless the base defines its own text structure tags; see the chapters on the individual bases.
The tei2.dtd file embeds the appropriate files for the base tag set previously selected by means of the parameter entities described in section 3.2 . A parameter entity for the file containing the relevant DTD fragment is declared and referred to inside a conditional marked section controlled by the appropriate parameter entity. The relevant fragment of tei2.dtd is this:
<!-- 3.6.4: Embed base tag set --> <!-- A different base will be embedded, depending on which --> <!-- parameter entity has been declared by the user with the --> <!-- value 'INCLUDE'. --> <![ %TEI.prose [ <!ENTITY % TEI.prose.dtd system 'teipros2.dtd' > %TEI.prose.dtd; ]]&nil;> <![ %TEI.verse [ <!ENTITY % TEI.verse.dtd system 'teivers2.dtd' > %TEI.verse.dtd; ]]&nil;> <![ %TEI.drama [ <!ENTITY % TEI.drama.dtd system 'teidram2.dtd' > %TEI.drama.dtd; ]]&nil;> <![ %TEI.spoken [ <!ENTITY % TEI.spoken.dtd system 'teispok2.dtd' > %TEI.spoken.dtd; ]]&nil;> <![ %TEI.dictionaries [ <!ENTITY % TEI.dictionaries.dtd system 'teidict2.dtd' > %TEI.dictionaries.dtd; ]]&nil;> <![ %TEI.terminology [ <!ENTITY % TEI.terminology.dtd system 'teiterm2.dtd' > %TEI.terminology.dtd; ]]&nil;> <![ %TEI.general [ <!ENTITY % TEI.general.dtd system 'teigen2.dtd' > %TEI.general.dtd; ]]&nil;> <![ %TEI.mixed [ <!ENTITY % TEI.mixed.dtd system 'teimix2.dtd' > %TEI.mixed.dtd; ]]&nil;> <!-- This fragment is used in sec. 3.6.1 -->
The tei2.dtd file embeds the appropriate files for any additional base tag set previously enabled by means of the parameter entities described in section 3.2 . A parameter entity for the file containing the relevant DTD fragment is declared and referred to, inside a conditional marked section controlled by the appropriate parameter entity. The relevant fragment of tei2.dtd is this:
<!-- 3.6.5: Embed additional tag sets --> <!-- These entities are declared and embedded only when the --> <!-- user has overridden the default declaration of IGNORE --> <!-- for a specific additional tag set. --> <![ %TEI.linking [ <!ENTITY % TEI.linking.dtd system 'teilink2.dtd' > %TEI.linking.dtd; ]]&nil;> <![ %TEI.analysis [ <!ENTITY % TEI.analysis.dtd system 'teiana2.dtd' > %TEI.analysis.dtd; ]]&nil;> <![ %TEI.fs [ <!ENTITY % TEI.fs.dtd system 'teifs2.dtd' > %TEI.fs.dtd; ]]&nil;> <![ %TEI.certainty [ <!ENTITY % TEI.certainty.dtd system 'teicert2.dtd' > %TEI.certainty.dtd; ]]&nil;> <![ %TEI.transcr [ <!ENTITY % TEI.transcr.dtd system 'teitran2.dtd' > %TEI.transcr.dtd; ]]&nil;> <![ %TEI.textcrit [ <!ENTITY % TEI.textcrit.dtd system 'teitc2.dtd' > %TEI.textcrit.dtd; ]]&nil;> <![ %TEI.names.dates [ <!ENTITY % TEI.names.dates.dtd system 'teind2.dtd' > %TEI.names.dates.dtd; ]]&nil;> <![ %TEI.nets [ <!ENTITY % TEI.nets.dtd system 'teinet2.dtd' > %TEI.nets.dtd; ]]&nil;> <![ %TEI.figures [ <!ENTITY % TEI.figures.dtd system 'teifig2.dtd' > %TEI.figures.dtd; ]]&nil;> <![ %TEI.corpus [ <!ENTITY % TEI.corpus.dtd system 'teicorp2.dtd' > %TEI.corpus.dtd; ]]&nil;> <!-- This fragment is used in sec. 3.6.1 -->
The TEI DTD contains over four hundred element types. To aid comprehension, modularity and modification, the majority of these elements are formally classified in some way. This section describes the various element classes recognized in the TEI DTD. Element classes are used to express two distinct kinds of commonality among elements. The elements of a class may share some set of SGML attributes, or they may appear in the same locations in the content models of the TEI DTDs, or both. A class is known as an a-class if its members share attributes, and as an m-class if its members appear at the same locations in the content models of other TEI elements. An element is said to inherit attributes, or the ability to appear at a given point in a document, from any classes of which it is a member. Classes may have subclasses and superclasses, and the characteristics of a superclass are inherited by all members of its subclasses.
Both types of element classes are represented in the TEI DTDs by parameter entities. For other uses of parameter entities in the TEI DTDs, see section 3.8 .
This section describes the major element classes of each type together with the formal declarations for their parameter entities, which are contained in the file teiclas2.ent . All element classes are documented in the alphabetical reference section in Part VII.
An attribute class (a-class) groups together elements which share some set of common attributes. For example, the members of the class names are all elements which contain proper nouns: e.g. <name> , <placeName> , or <persName> . All of these elements use the same attributes (key and reg ) to record information about the referent or the regularized form of the proper nouns. Similarly, the members of the pointer class share a set of attributes useful for managing cross-reference links and other pointers. [ see note 22 ]
The attributes shared by the members of an a-class are defined in a parameter entity; member elements inherit the attributes by referring to the parameter entity within their attribute-list declaration (examples below). This practice helps ensure that if the attribute definitions for the class change, all members of the class will automatically inherit the new definitions. Parameter entities used for this purpose form their names by taking the name of the class they define and prefixing the string `a.'; we refer to these entities as a-dot entities.
For example, the declaration for the names class includes attribute definitions for its two attributes reg and key :
<!-- 3.7.1: Sample class declaration -->
<!ENTITY % a.names '
reg CDATA #IMPLIED
key CDATA #IMPLIED' >
Members of the class typically inherit these definitions by referring to
a.names :
<!-- 3.7.1: Sample element declarations -->
<!-- The members of a class refer to its a-dot entity in -->
<!-- their attribute-list declaration, as shown here. -->
<!ELEMENT name - - (%phrase.seq;) >
<!ATTLIST name %a.global;
%a.names;
type CDATA #IMPLIED >
Subclasses of a-classes inherit the attributes of their superclass similarly, by referring to the a-dot entity of the superclass in defining their own a-dot entity. For example, the class xPointer is a subclass of the class pointer , as shown implicitly by the declaration of its a-dot entity:
<!-- 3.7.1: Sample subclass declaration, with inheritance -->
<!-- from superclass -->
<!ENTITY % a.xPointer ' %a.pointer;
to %extPtr; "DITTO"
doc ENTITY #IMPLIED
from %extPtr; "ROOT"' >
(For an explanation of the parameter entity extptr used in the above example, see section 3.8.3 .)
The a-classes declared in the core tag sets of these Guidelines are:
All elements are considered members of the class global and thus include a reference to a.global; in their attribute definition list declaration. Some tag sets add specialized attributes to the set of global attributes; these additions are declared in the `ent' file of each tag set, using the following entity names. If the tag set does not define new global attributes, no entity of this type is declared.
These entities are included in the teiclas2.ent file indirectly, when the entity-declaration files of each tag set are embedded, as shown below in section 3.7.6 . For purposes of documentation, these attributes are treated as if inherited by the class global from superclasses called terminology , etc., and are documented under the class name.
One further complication to the inheritance mechanism should be mentioned here. In rare cases, a member of an a-class may override the definition of an inherited attribute. For example, the element <anchor> inherits the global id attribute from the class global --- as does every other element. On <anchor> elements, however, id is not optional but required. The declaration of <anchor> therefore does not refer to the class global , but instead defines all the inherited attributes explicitly, using its own declaration for id and the default inherited declarations for the other global attributes:
<!-- 3.7.1: Sample of local declaration overriding inherited -->
<!-- attributes -->
<!-- ANCHOR overrides the default ID, but uses the default -->
<!-- declarations for the other global attributes. -->
<!ELEMENT anchor - O EMPTY >
<!ATTLIST anchor %a.analysis;
%a.linking;
%a.terminology;
lang IDREF %INHERITED
rend CDATA #IMPLIED
n CDATA #IMPLIED
%a.typed;
id ID #REQUIRED >
Because this declaration does not use the parameter entity a.global , clearly any change in the definition for that
entity will not be reflected in this declaration. Consequently, any
changes made to the global attributes as such will not be inherited by
the <anchor> element. Instead, such changes must be replicated
manually. Care must thus be taken in modifying attribute definitions
for a-classes if any members of the class override the inherited
definitions, to ensure that all members of the class really do get the
modified definitions.
<!-- 3.7.1: Attribute classes -->
<!ENTITY % a.declaring '
decls IDREFS #IMPLIED' >
<!ENTITY % a.declarable '
default (YES | NO) NO' >
<!ENTITY % a.divn '
sample (initial | medial | final |
unknown | complete) complete
part (Y | N | I | M | F) N
type CDATA #CURRENT
org (composite | uniform)
uniform' >
<!ENTITY % a.enjamb '
enjamb CDATA #IMPLIED' >
<!ENTITY % a.interpret '
resp CDATA %INHERITED
inst IDREFS #IMPLIED
type CDATA %INHERITED' >
<!ENTITY % a.metrical '
real CDATA #IMPLIED
met CDATA %INHERITED
rhyme CDATA #IMPLIED' >
<!ENTITY % a.names '
reg CDATA #IMPLIED
key CDATA #IMPLIED' >
<!ENTITY % a.personPart ' %a.names;
sort NUMBER #IMPLIED
type CDATA #IMPLIED
full (yes | abb | init) yes' >
<!ENTITY % a.placePart ' %a.names;
type CDATA #IMPLIED
full (yes | abb | init) yes' >
<!ENTITY % a.pointer '
crdate CDATA #IMPLIED
evaluate (all | one | none) #IMPLIED
resp CDATA #IMPLIED
targOrder (Y | N | U) U
type CDATA #IMPLIED
targType NAMES #IMPLIED' >
<!ENTITY % a.seg '
function CDATA #IMPLIED
part (Y | N | I | M | F) N
type CDATA #IMPLIED' >
<!ENTITY % a.temporalExpr '
reg CDATA #IMPLIED
value CDATA #IMPLIED
type CDATA #IMPLIED
full (yes | abb | init) yes' >
<!ENTITY % a.timed '
dur CDATA #IMPLIED
end IDREF #IMPLIED
start IDREF #IMPLIED' >
<!ENTITY % a.typed '
type CDATA #IMPLIED
subtype CDATA #IMPLIED' >
<!ENTITY % a.xPointer ' %a.pointer;
to %extPtr; "DITTO"
doc ENTITY #IMPLIED
from %extPtr; "ROOT"' >
<!-- This fragment is used in sec. 3.7.3 -->
When the members of a class are structurally similar and can appear at the same kinds of structural locations in the document, they are grouped together into an m-class (or `model-class'). M-classes are implemented by defining a parameter entity for use in the formal declaration of element content models. The parameter entity takes the name of the class it defines, and prefixes the string `m.', which can be interpreted as model or as members. The replacement text of the entity is a list of the members of the class, separated by `|', the SGML symbol for alternation.
For each class an additional entity is defined, which also takes the name of the class, this time prefixed by the string `x.' (for extension); the default value of these x-dot entities is always the empty string. A reference to the corresponding x-dot entity is always included within the replacement string for each m-dot entity. This enables an encoder to add new members to a class simply by declaring a new value for an x-dot entity.
For example, the class bibl has the three members <bibl> , <bibl.full> , and <bibl.struct> . Its content-model entity is defined thus:
<!ENTITY % x.bibl '' > <!ENTITY % m.bibl '%x.bibl bibl | bibl.full | bibl.struct' >With the default value of the x-dot entity, this is the same as defining m.bibl with the replacement text bibl | bibl.full | bibl.struct . If an encoder wishes to add a new bibliographic element called <myBib> , it can be added to the bibl class by redefining the x-dot entity thus:
<!ENTITY % x.bibl 'myBib |' >This changes the replacement text of m.bibl from its default value to myBib | bibl | bibl.full | bibl.struct . If more than one element is to be added to a class, the x-dot entity for the class should be redefined as a list of the new generic identifiers, each one (including the last) followed by a vertical bar. The same effect could be achieved simply by redefining the whole of the new m.bibl entity directly, but the x-dot method requires no repetition of the already existing members of the class and thus minimizes the chance of error.
Like a-classes, m-classes may have subclasses or superclasses. Just as elements inherit from a class the ability to appear in certain locations of a document (wherever the class can appear), so all members of a subclass inherit the ability to appear wherever any superclass can appear. Superclasses transmit their location characteristics to their subclasses by referring, in declaring their m-dot entity, to the m-dot entities of the subclasses.
For example, the class phrase includes the classes data , edit , hqphrase , loc , and seg as members, as can be seen in the declaration for its m-dot entity:
<!-- 3.7.2: Sample class declaration with inclusion of -->
<!-- subclasses -->
<!ENTITY % x.phrase '' >
<!ENTITY % m.phrase '%x.phrase %m.data; | %m.edit; |
%m.formPointers; | %m.hqphrase; | %m.loc; |
%m.phrase.verse; | %m.seg; | %m.sgmlKeywords; |
formula | fw | handShift' >
When the entity m.phrase is referred to in
content models, all members of all subclasses are included in the model.
The most important element classes used in TEI content models are declared in the DTD file teiclas2.ent , which is the default replacement text for the entity TEI.elementClasses and is embedded by the tei2.dtd file. These element classes are described, and their declarations reproduced, in the following sections.
The class system is structured around the following threefold division of elements:
Together the two sets of chunks and inter-level elements make up the set of:
Some elements belong to none of these classes; these include high-level structural elements like <tei.2> and <group> as well as some specialized elements which appear only within particular structures (like <analytic> , <monographic> , and <series> ). The majority of elements found in normal running text, however, are assigned by the TEI DTDs to one or the other of these classes.
Some component elements (e.g. <p> or <note> ) are common to all base tag sets, while others are unique to individual tag sets. This distinction is reflected in the parameter entity declarations, as shown below.
The teiclas2.ent file has the following overall structure:
<!-- 3.7.3: Element classes for TEI DTDs --> <!-- Text Encoding Initiative: Guidelines for Electronic --> <!-- Text Encoding and Interchange. Document TEI P3, 1994. --> <!-- Copyright (c) 1994 ACH, ACL, ALLC. Permission to copy --> <!-- in any form is granted, provided this notice is --> <!-- included in all copies. --> <!-- These materials may not be altered; modifications to --> <!-- these DTDs should be performed as specified in the --> <!-- Guidelines in chapter "Modifying the TEI DTD." --> <!-- These materials subject to revision. Current versions --> <!-- are available from the Text Encoding Initiative. --> <!-- First, we declare the 'low-level' core classes: these --> <!-- are classes of semantically and structurally similar --> <!-- elements declared as part of the core tag set, e.g. the --> <!-- classes 'data' or 'edit'. --> <!-- ... declarations from section 3.7.4 --> <!-- (Low-level classes) --> <!-- go here ... --> <!-- ... declarations from section 3.7.9 --> <!-- (Misc. Element Class Models) --> <!-- go here ... --> <!-- Next, we declare the 'high-level' classes: these group --> <!-- together all phrase-level elements, all inter-level --> <!-- elements, and all chunk-level elements in the core, and --> <!-- identify the 'common' component elements (chunks and --> <!-- inter-level elements), as opposed to the --> <!-- tagset-specific components. --> <!-- ... declarations from section 3.7.5 --> <!-- (Common high-level classes) --> <!-- go here ... --> <!-- Next, we embed the portions of each base and additional --> <!-- tag set which declare relevant parameter entities. Only --> <!-- those files are embedded which have been selected by --> <!-- the user in the DTD subset. These files will declare --> <!-- parameter entities for their component-level elements, --> <!-- as well as for any global attributes they define. --> <!-- ... declarations from section 3.7.6 --> <!-- (Embedding tag-set-specific entity definitions) --> <!-- go here ... --> <!-- We can now declare the standard content models; one of --> <!-- these varies with the base selected. --> <!-- ... declarations from section 3.7.7 --> <!-- (Standard Content Models) --> <!-- go here ... --> <!-- Finally, we declare the attribute classes, including --> <!-- the global attributes. --> <!-- ... declarations from section 3.7.1 --> <!-- (Attribute classes) --> <!-- go here ... --> <!-- ... declarations from section 3.5 --> <!-- (Global attributes) --> <!-- go here ... -->
The following low-level classes group together sets of semantically or structurally similar elements. These classes may include both elements in the core and elements declared in particular tag sets; a reference is given at least to the relevant section on the core tags.
The following are phrase-level element classes:
The following are inter-level element classes:
The following classes of elements may appear anywhere within the <text> element:
The entity declarations for these classes are these:
<!-- 3.7.4: Low-level classes -->
<!-- Most of these elements are in the core tag set, but -->
<!-- some may be from other tag sets. -->
<!-- Phrase-level classes -->
<!ENTITY % x.hqphrase '' >
<!ENTITY % m.hqphrase '%x.hqphrase distinct | emph | foreign |
gloss | hi | mentioned | soCalled | term | title' >
<!ENTITY % x.date '' >
<!ENTITY % m.date '%x.date date | dateRange | dateStruct' >
<!ENTITY % x.data '' >
<!ENTITY % m.data '%x.data abbr | address | date | dateRange |
dateStruct | expan | geogName | lang | measure |
name | num | orgName | persName | placeName | rs |
time | timeRange | timeStruct' >
<!ENTITY % x.edit '' >
<!ENTITY % m.edit '%x.edit add | app | corr | damage | del |
orig | reg | restore | sic | space | supplied |
unclear' >
<!ENTITY % x.loc '' >
<!ENTITY % m.loc '%x.loc link | ptr | ref | xptr | xref' >
<!ENTITY % x.seg '' >
<!ENTITY % m.seg '%x.seg c | cl | m | phr | s | seg | w' >
<!ENTITY % x.sgmlKeywords '' >
<!ENTITY % m.sgmlKeywords '%x.sgmlKeywords att | gi | tag |
val' >
<!ENTITY % x.phrase.verse '' >
<!ENTITY % m.phrase.verse '%x.phrase.verse caesura' >
<!ENTITY % x.formPointers '' >
<!ENTITY % m.formPointers '%x.formPointers oRef | oVar | pRef |
pVar' >
<!ENTITY % x.metadata '' >
<!ENTITY % m.metadata '%x.metadata alt | altGrp | certainty |
fLib | fs | fsLib | fvLib | index | interp |
interpGrp | join | joinGrp | link | linkGrp |
respons | span | spanGrp | timeline' >
<!ENTITY % x.refsys '' >
<!ENTITY % m.refsys '%x.refsys cb | lb | milestone | pb' >
<!ENTITY % x.editIncl '' >
<!ENTITY % m.editIncl '%x.editIncl addSpan | delSpan | gap' >
<!ENTITY % x.globincl '' >
<!ENTITY % m.globincl '%x.globincl %m.editIncl; | %m.metadata;
| %m.refsys; | anchor' >
<!-- Inter-level classes -->
<!ENTITY % x.hqinter '' >
<!ENTITY % m.hqinter '%x.hqinter cit | q | quote' >
<!ENTITY % x.bibl '' >
<!ENTITY % m.bibl '%x.bibl bibl | biblFull | biblStruct' >
<!ENTITY % x.lists '' >
<!ENTITY % m.lists '%x.lists label | list | listBibl' >
<!ENTITY % x.notes '' >
<!ENTITY % m.notes '%x.notes note | witDetail' >
<!ENTITY % x.stageDirection '' >
<!ENTITY % m.stageDirection '%x.stageDirection camera | caption
| move | sound | tech | view' >
<!-- This fragment is used in sec. 3.7.3 -->
The following element classes are used to implement the threefold structural distinction among phrases, chunks, and intermediate elements discussed above in section 3.7.3 . In this terminology, chunks (or chunk elements are elements which can occur only in chunk-level sequences (e.g. between but not within paragraphs); inter-level elements can occur either within chunks (at phrase-level) or between chunks (e.g. at paragraph-level), and phrase-level elements can occur only at phrase level, within chunks (e.g. within but not between paragraphs).
The element class common includes all component-level (chunk- and inter-level) elements common to more than one base. It is used in implementing the combined bases described in section 3.4 .
The relevant portion of the DTD looks like this:
<!-- 3.7.5: Common high-level classes -->
<!-- These are the three fundamental element classes. -->
<!ENTITY % x.phrase '' >
<!ENTITY % m.phrase '%x.phrase %m.data; | %m.edit; |
%m.formPointers; | %m.hqphrase; | %m.loc; |
%m.phrase.verse; | %m.seg; | %m.sgmlKeywords; |
formula | fw | handShift' >
<!ENTITY % x.inter '' >
<!ENTITY % m.inter '%x.inter %m.bibl; | %m.hqinter; | %m.lists;
| %m.notes; | %m.stageDirection; | castList | figure
| stage | table | text' >
<!ENTITY % x.chunk '' >
<!ENTITY % m.chunk '%x.chunk ab | eTree | graph | l | lg | p |
sp | tree | witList' >
<!-- This class isolates all the common component-level -->
<!-- elements. -->
<!ENTITY % x.common '' >
<!ENTITY % m.common '%x.common %m.bibl; | %m.chunk; |
%m.hqinter; | %m.lists; | %m.notes; | stage' >
<!-- This fragment is used in sec. 3.7.3 -->
The following element classes are used to group together component-level elements which are allowed only in texts of a particular type (i.e. texts using a specific base).
Declarations for these base-specific element classes are included in the entity file of each base, which is in turn embedded by the teiclas2.dtd file in the DTD fragment shown below. If the tag set defines additions to the set of global attributes, or declares a class of component-level elements unique to the tag set, then it has an entity file which is embedded here; otherwise not.
<!-- 3.7.6: Embedding tag-set-specific entity definitions --> <![ %TEI.verse [ <!ENTITY % TEI.verse.ent system 'teivers2.ent' > %TEI.verse.ent; ]]&nil;> <![ %TEI.drama [ <!ENTITY % TEI.drama.ent system 'teidram2.ent' > %TEI.drama.ent; ]]&nil;> <![ %TEI.spoken [ <!ENTITY % TEI.spoken.ent system 'teispok2.ent' > %TEI.spoken.ent; ]]&nil;> <![ %TEI.dictionaries [ <!ENTITY % TEI.dictionaries.ent system 'teidict2.ent' > %TEI.dictionaries.ent; ]]&nil;> <![ %TEI.terminology [ <!ENTITY % TEI.terminology.ent system 'teiterm2.ent' > %TEI.terminology.ent; ]]&nil;> <![ %TEI.linking [ <!ENTITY % TEI.linking.ent system 'teilink2.ent' > %TEI.linking.ent; ]]&nil;> <![ %TEI.analysis [ <!ENTITY % TEI.analysis.ent system 'teiana2.ent' > %TEI.analysis.ent; ]]&nil;> <![ %TEI.transcr [ <!ENTITY % TEI.transcr.ent system 'teitran2.ent' > %TEI.transcr.ent; ]]&nil;> <![ %TEI.textcrit [ <!ENTITY % TEI.textcrit.ent system 'teitc2.ent' > %TEI.textcrit.ent; ]]&nil;> <![ %TEI.names.dates [ <!ENTITY % TEI.names.dates.ent system 'teind2.ent' > %TEI.names.dates.ent; ]]&nil;> <![ %TEI.figures [ <!ENTITY % TEI.figures.ent system 'teifig2.ent' > %TEI.figures.ent; ]]&nil;> <!-- This fragment is used in sec. 3.7.3 -->
As far as possible, the TEI DTDs use the following set of frequently-encountered content models, to help achieve consistency among different elements.
The relevant portion of the DTD looks like this:
<!-- 3.7.7: Standard Content Models --> <!-- Here we declare the parameter entities phrase, --> <!-- phrase.seq, component, component.seq, paraContent, and --> <!-- specialPara, for use in the content models of element --> <!-- declarations. --> <!-- The entities phrase and phrase.seq are the same in all --> <!-- bases. They may include elements specific to single tag --> <!-- sets; if the tag set is not selected, these elements --> <!-- are undefined and have no effect. --> <!ENTITY % phrase '(#PCDATA | %m.phrase)' > <!ENTITY % phrase.seq '(%phrase;)*' > <!-- The entity component varies with the base. The versions --> <!-- for the combined bases are declared first (so as to --> <!-- take precedence over the declarations in the individual --> <!-- bases). --> <!-- ... declarations from section 3.7.8 --> <!-- (Definition of components for combined bases) --> <!-- go here ... --> <![ %TEI.prose [ <!ENTITY % component '(%m.common)' > <!ENTITY % TEI.singleBase 'INCLUDE' > ]]&nil;> <![ %TEI.verse [ <!ENTITY % component '(%m.common | %m.comp.verse)' > <!ENTITY % TEI.singleBase 'INCLUDE' > ]]&nil;> <![ %TEI.drama [ <!ENTITY % component '(%m.common | %m.comp.drama)' > <!ENTITY % TEI.singleBase 'INCLUDE' > ]]&nil;> <![ %TEI.spoken [ <!ENTITY % component '(%m.common | %m.comp.spoken)' > <!ENTITY % TEI.singleBase 'INCLUDE' > ]]&nil;> <![ %TEI.dictionaries [ <!ENTITY % component '(%m.common | %m.comp.dictionaries)' > <!ENTITY % TEI.singleBase 'INCLUDE' > ]]&nil;> <![ %TEI.terminology [ <!ENTITY % component '(%m.common | %m.comp.terminology)' > <!ENTITY % TEI.singleBase 'INCLUDE' > ]]&nil;> <!-- Default declaration. --> <!ENTITY % component '(%m.common)' > <!ENTITY % TEI.singleBase 'INCLUDE' > <!-- The entity component.seq is always a starred sequence --> <!-- of component elements. Its definition does not vary --> <!-- with the base (unless we are using the general base, in --> <!-- which case it has already been defined above), but the --> <!-- meaning of the definition does. --> <!ENTITY % component.seq '(%component;)*' > <!-- The following entities do not vary with the base. --> <!ENTITY % paraContent '(#PCDATA | %m.phrase | %m.inter)*' > <!ENTITY % specialPara '(((%m.chunk), (%component.seq)) | (%paraContent))' > <!-- This fragment is used in sec. 3.7.3 -->
When the mixed or general base is in use, the definitions of the entities component and component.seq are rather more complex. The relevant portion of the DTD is this:
<!-- 3.7.8: Definition of components for combined bases --> <!-- Default declarations for the 'mix.' entities used for --> <!-- mixed and general bases. --> <!ENTITY % mix.verse '' > <!ENTITY % mix.drama '' > <!ENTITY % mix.spoken '' > <!ENTITY % mix.dictionaries '' > <!ENTITY % mix.terminology '' > <![ %TEI.mixed [ <!ENTITY % TEI.singleBase 'IGNORE' > <!-- The mixed base allows components from any base; it does --> <!-- so by defining 'component' as including both common --> <!-- components and those specific to one tag set. --> <!ENTITY % component '(%m.common %mix.verse %mix.drama %mix.spoken %mix.dictionaries %mix.terminology)' > ]]&nil;> <![ %TEI.general [ <!-- The general base uses the same definition of component --> <!-- as the mixed base. --> <!ENTITY % TEI.singleBase 'IGNORE' > <!ENTITY % component '(%m.common %mix.verse %mix.drama %mix.spoken %mix.dictionaries %mix.terminology)' > <!-- But it defines a special version of component.seq, --> <!-- which restricts each div of the text to a single base: --> <!-- bases can shift only in embedded divs or at div --> <!-- boundaries. This entity is constructed out of a series --> <!-- of smaller entities, one for each tag set. If the tag --> <!-- set is not in use, its entity will expand to the empty --> <!-- string. --> <![ %TEI.verse [ <!-- If the verse base is in use, ... --> <!ENTITY % gen.verse '((%m.comp.verse), (%m.common | %m.comp.verse)*) |' > ]]&nil;> <![ %TEI.drama [ <!-- If the drama base is in use, ... --> <!ENTITY % gen.drama '((%m.comp.drama), (%m.common | %m.comp.drama)*) |' > ]]&nil;> <![ %TEI.spoken [ <!-- If the spoken base is in use, ... --> <!ENTITY % gen.spoken '((%m.comp.spoken), (%m.common | %m.comp.spoken)*) |' > ]]&nil;> <![ %TEI.dictionaries [ <!-- If the dictionary base is in use, ... --> <!ENTITY % gen.dictionaries '((%m.comp.dictionaries), (%m.common | %m.comp.dictionaries)*) |' > ]]&nil;> <![ %TEI.terminology [ <!-- If the terminology base is in use, ... --> <!ENTITY % gen.terminology '((%m.comp.terminology), (%m.common | %m.comp.terminology)*) |' > ]]&nil;> <!-- Default declarations for all the entities gen.verse, --> <!-- etc. --> <!ENTITY % gen.verse '' > <!ENTITY % gen.drama '' > <!ENTITY % gen.spoken '' > <!ENTITY % gen.dictionaries '' > <!ENTITY % gen.terminology '' > <!-- Now we are ready to declare component.seq and --> <!-- component.plus for use in general base tag set. --> <!ENTITY % component.seq '(%m.common)*, (%gen.verse %gen.drama %gen.spoken %gen.dictionaries %gen.terminology TEI...end)?' > <!ENTITY % component.plus '(%gen.verse %gen.drama %gen.spoken %gen.dictionaries %gen.terminology TEI...end) | ( (%m.common)+, (%gen.verse %gen.drama %gen.spoken %gen.dictionaries %gen.terminology TEI...end)?' > <!-- (End of marked section for general base.) --> ]]&nil;> <!-- This fragment is used in sec. 3.7.7 -->
The following element classes occupy specific places in content models; some are relevant only when certain tag sets are selected
They are declared in the following DTD fragment:
<!-- 3.7.9: Misc. Element Class Models -->
<!ENTITY % x.agent '' >
<!ENTITY % m.agent '%x.agent name' >
<!ENTITY % x.addrPart '' >
<!ENTITY % m.addrPart '%x.addrPart name | postBox | postCode |
street' >
<!ENTITY % x.biblPart '' >
<!ENTITY % m.biblPart '%x.biblPart analytic | author |
biblScope | edition | editor | extent | idno |
imprint | monogr | note | publisher | pubPlace |
respStmt | series' >
<!ENTITY % x.demographic '' >
<!ENTITY % m.demographic '%x.demographic affiliation | birth |
education | firstLang | langKnown | occupation |
persName | residence | socecStatus' >
<!ENTITY % x.divbot '' >
<!ENTITY % m.divbot '%x.divbot byline | closer | dateline |
epigraph | salute | signed | trailer' >
<!ENTITY % x.divtop '' >
<!ENTITY % m.divtop '%x.divtop argument | byline | dateline |
docAuthor | docDate | epigraph | head | opener |
salute | signed' >
<!ENTITY % x.dramafront '' >
<!ENTITY % m.dramafront '%x.dramafront castList | epilogue |
performance | prologue | set' >
<!ENTITY % x.front '' >
<!ENTITY % m.front '%x.front %m.dramafront; | divGen |
titlePage' >
<!ENTITY % x.personPart '' >
<!ENTITY % m.personPart '%x.personPart addName | forename |
genName | nameLink | roleName | surname' >
<!ENTITY % x.placePart '' >
<!ENTITY % m.placePart '%x.placePart bloc | country | distance
| geog | offset | region | settlement' >
<!ENTITY % x.tpParts '' >
<!ENTITY % m.tpParts '%x.tpParts byline | docAuthor | docDate |
docEdition | docImprint | docTitle | epigraph |
figure | imprimatur | titlePart' >
<!ENTITY % x.fmchunk '' >
<!ENTITY % m.fmchunk '%x.fmchunk argument | byline | docAuthor
| docDate | docEdition | docImprint | docTitle |
epigraph | head | titlePart' >
<!-- This fragment is used in sec. 3.7.3 -->
The TEI DTDs use SGML parameter entities for several purposes:
The parameter entities used to specify which base tag set and which additional tag sets are to be used in a given document are listed in section 3.2 . Their default definition is always ``IGNORE'': the encoder selects the TEI base and additional tag sets by declaring the appropriate parameter entities with the entity text ``INCLUDE''.
The DTD and entity files are listed in section 3.2 ; if the standard TEI entities are modified to point at locally developed DTD files containing local modifications or extensions to the TEI DTDs, the use of the standard parameter entity names ensures that the modification will be obvious upon examination of the document's DTD.
The following entities are referred to by the main tei2.dtd file to embed portions of the TEI DTDs or locally developed extensions.
The TEI DTDs use marked sections and parameter entity references to allow users to exclude the definitions of individual elements, in order either to make the elements illegal in a document or to allow the element to be redefined, as further described in chapter 29 .
Parameter entities used for this purpose have exactly the same name as the generic identifier of the element concerned. The default definition for these parameter entities is ``INCLUDE'' but they may be changed to ``IGNORE'' in order to exclude the standard element and attribute definition list declarations from the DTD.
The declarations for the element <p> , for example, are preceded by a definition for a parameter entity with the name p and contained within a marked section whose keyword is given as ``%p;'':
<!ENTITY % p 'INCLUDE' >
<![ %p; [
<!-- element and attlist declaration for p here -->
]]>
These parameter entities are defined immediately preceding the element whose declarations they control; because their names are completely regular, they are not documented individually in the reference section of this document.
In the TEI DTDs, elements are not referred to directly by their generic identifiers; instead, the DTDs refer to parameter entities which expand to the standard generic identifiers. This allows users to rename elements by redefining the appropriate parameter entity (as described more fully in chapter 29 ). Parameter entities used for this purpose are formed by taking the standard name (generic identifier) of the element and attaching the string ``n.'' as a prefix. Thus the standard generic identifiers for paragraphs, notes, and quotations, <p> , <note> , and <q> are defined by declarations of the following form:
<!ENTITY % n.p 'p' > <!ENTITY % n.note 'note' > <!ENTITY % n.q 'q' >
Since by default parameter entities are case-sensitive, the specific mix of upper and lower case letters in the standard name must be preserved in the entity name.
The formal declarations of the parameter entities used for generic identifiers are contained in the file teigis2.ent ; since their names and replacement texts are fully predictable, these parameter entities are not individually documented in the reference section of these Guidelines. The parameter entity TEI.elementNames is used to embed the file teigis2.ent in the DTD. A full set of alternate generic identifiers can be substituted for the standard set by defining TEI.elementNames to point at a different file. [ see note 24 ]
The TEI uses the following parameter entities to signal information which cannot be expressed using SGML keywords:
The parameter entity INHERITED is used to signal that the default value for an attribute should be inherited from an enclosing element. The definition for INHERITED is the string ``#IMPLIED''; as for all implied defaults, the application program is responsible for deducing the default attribute value when no value is specified in the element start-tag. Since the parameter entity is resolved by the SGML parser, the application program will see no difference between attributes whose default is ``%INHERITED'' and those whose default is ``#IMPLIED'' --- information about which attribute values are inherited and which are inferred in some other way must be built into the application in advance.
The parameter entity ISO-date is used to signal that the value for an attribute should be an ISO-standard date value; in this notation, [ see note 25 ] a date like ``September 22, 1968'' would be written ``1968-09-22''. The parameter entity ISO-date expands to ``CDATA''.
The keywords controlling the selection of base and additional tag sets (described in section 3.2 ) all have the default value ``IGNORE''; the user can override this by a local declaration, as described in section 3.3 .
The parameter entities for TEI keywords are included in file teikey2.dtd , which is the default replacement text for the entity TEI.keywords and is embedded by the file tei2.dtd .
The file teikey2.dtd has the following contents:
<!-- 3.8.3: TEI Keywords --> <!-- I. Declare TEI keywords for data types. --> <!-- These parameter entities are used as keywords to --> <!-- express rules or constraints which cannot be fully --> <!-- expressed in SGML; their expansions show the nearest --> <!-- SGML equivalent. --> <!ENTITY % INHERITED '#IMPLIED' > <!ENTITY % ISO-date 'CDATA' > <!ENTITY % extPtr 'CDATA' > <!-- II. Declare keywords for tag-set selection. --> <!-- Declare all bases and additional tag sets as 'IGNORE'. --> <!-- The user can override this default by declaring the --> <!-- same entity with the replacement text 'INCLUDE', in the --> <!-- document's DTD subset. --> <!-- Base tag sets first. --> <!ENTITY % TEI.prose 'IGNORE' > <!ENTITY % TEI.verse 'IGNORE' > <!ENTITY % TEI.drama 'IGNORE' > <!ENTITY % TEI.spoken 'IGNORE' > <!ENTITY % TEI.dictionaries 'IGNORE' > <!ENTITY % TEI.terminology 'IGNORE' > <!-- Now the mixed bases. --> <!ENTITY % TEI.general 'IGNORE' > <!ENTITY % TEI.mixed 'IGNORE' > <!-- Now additional tag sets. --> <!ENTITY % TEI.linking 'IGNORE' > <!ENTITY % TEI.analysis 'IGNORE' > <!ENTITY % TEI.fs 'IGNORE' > <!ENTITY % TEI.certainty 'IGNORE' > <!ENTITY % TEI.transcr 'IGNORE' > <!ENTITY % TEI.textcrit 'IGNORE' > <!ENTITY % TEI.names.dates 'IGNORE' > <!ENTITY % TEI.nets 'IGNORE' > <!ENTITY % TEI.figures 'IGNORE' > <!ENTITY % TEI.corpus 'IGNORE' >
The relevant portion of the main DTD looks like this:
<!-- 3.8.3: TEI Keywords --> <!-- We declare and immediately embed the TEI keywords file. --> <!ENTITY % TEI.keywords.ent system 'teikey2.ent' > %TEI.keywords.ent; <!-- This fragment is used in sec. 3.6.1 -->
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