## Occurrences of Concur References Outside of Chapter 31: Multiple Hierarchies

As a supplement to my comments on Chapter 31, I have also attempted to isolate all references to concurrent markup in the P4 drafts. I ran grep on concur, hierarchy, hierarchies, hierarchical, and overlapping (in various case) against the HTML source for all the TEI P3 chapters. (I have also appended those results just in case I engaged in the old scribal tradition of dittography or my attention lapsed while reading the output of those efforts.) Hopefully I caught most of the references. Since we don't have access to the XML source, I simply cut-n-pasted those passages below, indicating the chapter of occurrence and suggested revision/rewording, etc. Each chapter begins with a <H3> header and individual passages within the chapter are separated by <H4> headers for their section. Crude but hopefully easier to use than searching for references in an entire chapter of prose.

### 2 A Gentle Introduction to SGML

#### 2.3.2 Content Models: An Example

#### 2.5 Complicating the Issue: More on Element Declarations

To deal with the first case, SGML provides the exception mechanism; to deal with the second, SGML permits the definition of `concurrent' document structures.

Since both concur and exceptions are not allowed in XML, suggest deletion of entire sentence. The section entitled: "2.5.1 Exceptions to the Content Model" should be deleted in its entirety.

#### 2.5.2 Concurrent Structures

Actually I like the illustration of the overlapping hierarchy problem but obviously the remarks on concur:

That is, a page consists of one or more unnamed groups, each of which contains an optional title, followed by a sequence of lines. (Note, incidentally, that this model prohibits a title appearing on its own at the foot of a page). However, simply inserting the element into the hierarchy already defined is not as easy as it might seem. Some poems are longer than a single page, and other pages contain more than one poem. We cannot therefore insert the element page between anthology and poem in the hierarchy, nor can it go between poem and stanza, nor yet in both places at once! What is needed is the ability to create a separate hierarchy, with the same elements at the bottom (the stanzas, lines and titles), but combined into a different superstructure. This is the ability which the CONCUR feature of SGML gives. down to:

A note of caution is appropriate: CONCUR is an optional feature of SGML, and not all available SGML software systems support it, while those which do, do not always do so according to the letter of the standard. For that reason, if for no other, wherever these Guidelines have identified a potential application of CONCUR, they also invariably suggest alternative methods as well. For fuller discussion of these issues, see chapter 31 Multiple Hierarchies. needs to be deleted. That closing paragraph could be re-written to say:

Earlier editions of these Guidelines treated multiple hierarchies with an optional feature of SGML (CONCUR). The CONCUR feature of SGML is not availabe in XML and was poorly supported by SGML software. Alternative methods to CONCUR are identified in Chapter 31, Multiple Hierarchies.

### 5 The TEI Header

#### 5.3.5 The Reference System Declaration

A reference declaration can only describe the referencing system applicable to a single document type; if therefore concurrent document types are in use (as discussed in section 6.9 Reference Systems), a refsDecl element must be supplied for each; the doctype attribute should be used to specify the document type to which the declaration relates.

### 6 Elements Available in All TEI Documents

#### 6.3.3 Quotation

the quotation is marked up as part of a concurrent but independent hierarchy

#### 6.9 Reference Systems

where a reference system exists which is not based on the same logical structure as that of the text's markup, (for example, one based on the page and line numbers of particular editions of the text rather than on the structural divisions of it), then a distinct logical structure representing the reference system may be encoded as a concurrent markup stream, as described in section 31.6 Concurrent Markup for Pages and Lines.

#### 6.9.1 Using the ID and N Attributes

Using the n attribute one can specify only a single standard referencing system, a limitation not without problems, since some editions may define structural units differently and thus create alternative reference systems. For example, another edition of the Amores considers poem 10 a continuation of poem 9, and therefore would specify the same line as `Amores 2.9.31'. In order to record both of these reference systems, one must either use the id or n attribute for one, with competing systems in concurrent markup hierarchies, as discussed below in section 31.6 Concurrent Markup for Pages and Lines , or else use the mileStone tags described in section 6.9.3 Milestone Tags.

Should this be further reformed to simply point to Chapter 31? Not sure we should leave the impression here that milestones are the only choice.

#### 6.9.2 Creating New Reference Systems

When the hierarchy of the encoded document and that of the reference system differ (e.g. for reference systems based on page and line numbers) or when more than one reference system is to be encoded, the encoder may choose to represent the alternative reference system(s) as elements in one or more concurrent document hierarchies. For an introduction to the concept of concurrent hierarchies, see the discussion of the CONCUR feature in section 2.5.2 Concurrent Structures. For further discussion of this and other mechanisms, see chapter 31 Multiple Hierarchies.

#### 6.9.3 Milestone Tags

If concurrent markup is not desired (e.g. because the document is XML, or because the available SGML parser does not support the CONCUR feature), or if the desired reference system does not correspond to any particular structural hierarchy, it may be more convenient to mark up changes in the reference system by using one or more of the following milestone elements:

Sugessted revision:XML does not support concurrent markup but one method of representing overlapping hierarchies or reference systems that do not correspond to any particular structural hierarchy is to use one or more of the following milestone elements:

#### 6.12 Overview of the Core Tag Set

Except for those tags designed to be used in concurrent markup streams, a All the elements described in this chapter occur in the core of TEI tags, defined by the following DTD fragment.

### 10 Base Tag Set for Drama

#### 10.2.2 Speeches and Speakers

SGML's CONCUR feature (not available in XML) also allows for two (or more) such conflicting hierarchic views to be presented in a single document. For more detailed discussion and examples of alternative treatments of this fundamental issue, refer to chapter 31 Multiple Hierarchies.

### 11 Transcriptions of Speech

#### 11.3.1 Segmentation

a concurrent DTD may be defined

#### 11.3.6 Analytic Coding

Where a more sophisticated analysis is needed, more sophisticated methods of markup will also be appropriate, for example, using concurrent markup streams to indicate multiple segmentation of the stream of discourse, or complex alignment of several segments within it.

### 28 Conformance

#### 28.2 Modifications to TEI SGML Declaration

in the FEATURES clause, CONCUR may be set to NO if concurrent markup is not used in the document.

### 36 Obtaining the TEI DTD

teipl2.dtd: tags for concurrent markup of pages and lines

### 39 Formal Grammar for the TEI-Interchange-Format Subset of SGML

I assume chapter 39 is to be completely re-written and so have not noted references to CONCUR in it.

Patrick Durusau, Society of Biblical Literature, pdurusau@emory.edu
September 2, 2001