data.pattern

data.pattern (regular expression pattern) defines attribute values which are expressed as a regular expression.
Moduletei — The TEI Infrastructure
Used by
Class:
Element:
Declaration

<rng:define name="data.pattern">
 <rng:data type="token"/>
</rng:define>
data.pattern = token
Note
A regular expression, often called a pattern, is an expression that describes a set of strings. They are usually used to give a concise description of a set, without having to list all elements. For example, the set containing the three strings Handel, Händel, and Haendel can be described by the pattern H(ä|ae?)ndel (or alternatively, it is said that the pattern H(ä|ae?)ndel matches each of the three strings)
Wikipedia