Punctum delens

Punctum delens is the name given to marks (usually a point, but also small x, underlining, or strikethrough) used to indicate deletion. Dots are also found above or below individual letters in several spelling systems, including Irish (where a raised dot often called a punctum delens was used to indicate lenition until the middle of the last century) and various transliteration systems for Arabic.

When used to indicate deletion, the punctum delens (and equivalent) represents the structural category deletion. Most markup languages (including strict XHTML 1.0/HTML 4.0, and TEI), therefore, do have a relevant element.

When used as part of a spelling system, the dot is either part of the "letter" in question, or a diacritic. In such cases, it is not a structural category and does not have a corresponding element in most structural markup languages. Representation in such cases is by Unicode.

Print documents
The Punctum delens (and equivalent) is less common in print than in manuscript sources. The most common usage is probably in legal and electronic documents, including wordprocessor files, where strikethrough is often used to mark deleted text during the drafting stage. (Dots found above or below letters in spelling systems such as pre-mid-twentieth-century Irish and most Arabic transliteration systems are not (structurally speaking) true examples of the punctum; they should not be treated as deletion).

Manuscripts
The Punctum delens (and equivalent) is far more common in manuscript sources; indeed, if we extend the category to include scoring or any other mark of deletion, it is probably universal.

Structural encoding
Because Unicode has several dot-like diacritics, it is very easy (and tempting) to reproduce the punctum delens as a type-facsimile rather than in structural markup. This is a mistake, however: the punctum is properly speaking a feature of layout rather than orthography and hence only accidentally similar to the Unicode symbols. The correct way of encoding a "punctum" structurally is to use an element such as html:del or tei:del. Conversely, when the dot above or below a letter is part of the orthography of the language in question, it should be encoded in Unicode rather than structural markup.

(X)HTML
In Strict (X)HTML, deleted text in print or manuscript sources is encoded using the following structural element:

&lt;del&gt;: Deletion

Most visual commercial browsers render the this element by default using strikethrough. The appearance of this (and most other) elements can also be controlled by external (e.g. CSS) stylesheets. See below, [[#Stylesheets|Stylesheets].

TEI
In TEI XML (P4), text marked by a punctum (or equivalent) is commonly encoded using the following structural element:

&lt;del&gt;: Deletion

Most commercial browsers do not have a default stylesheet for this (or any other) TEI element. Its display characteristics therefore must be controlled by stylesheets, either directly (i.e. using a formatting stylelanguage such as CSS or XSL-FO), or indirectly, after conversion to XHTML for display.

Stylesheets
There is no fixed convention for representing the punctum delens in print transcriptions of medieval manuscripts. Because strikethrough is used widely in print to represent an equivalent structural category, however, this is probably the best bet for presentation. Underlining, which appears as a deletion mark in some manuscripts and has been used in the past in some print transcriptions is not recommended: this is used for insertion by in many legal documents and electronic texts. The construction of type-facsimiles using Unicode is not recommended.

CSS
Strikethrough (and underlining) in CSS is controlled by the font-decoration property. All textual elements can be assigned a value for this property. The relevant value for strikethrough is

line-through

Other permissable values include

overline underline blink

Example
del { text-decoration: line-through; }

XSLT
There is no relevant category in XSLT.

XSL-FO
(Unknown)

LaTeX
(Unknown)