XML Schema Complete Reference, The

Chapter 14. Regular Expressions

IN THIS CHAPTER

14.1 Concepts and Observations

14.2 Regular Expression Syntax

14.3 Constraining Simple Content

A regular expression is a pattern for identifying a range of string values. This pattern conforms to a specific grammar. The Schema Recommendation suggests that an XML validator should implement “Level 1” regular expressions as defined in the Unicode Regular Expression Guidelines. These guidelines reside at http://unicode.org/unicode/reports/tr18/.

An expression (without “regular”) is a regular expression snippet, or a part of a regular expression. An expression may match one or many characters. An expression may comprise an entire regular expression.

Notation Note

In this chapter, all strings that might ...