Practical Programming in Tcl & Tk, Third Edition By Brent B. Welch
Table of Contents
Chapter 52. Tcl/Tk 8.1
An all new regular expression implemenation supports Unicode and Advanced Regular Expressions, which are described in detail in Chapter 11. The new regular expression syntax has been added in a way that is compatible with earlier versions of regular expressions. There are also new regexp and regsub command options to control the new regular expression engine.
