Rating: 

undoubtedly the most thorough and unified coverage of this important

topic. A treatise such as this is appropriate in light of the large

number of programs, both interactive and command line, that use regular

expressions with feature sets that vary from program to program. Many

references on specific languages contain chapters on the use of regular

expressions within the language, but they lack the unifying thrust of

this book. Friedl's book also considers the issue of efficiency in the

use of regular expressions, a topic not normally examined elsewhere.

The book covers regular expressions in general followed by specific

coverage of regular expressions in three languages, Perl, Java, and .net.

A major omission here in my view is JavaScript. The newer versions of

JavaScript have a powerful regular expression capability and, unlike the

other languages considered, JavaScript occurs in a context where there is

no other choice of language, in interactive pages in web browsers. Another

language that gets short-changed is TCL (Tool Command Language) which has

a very powerful and efficient regular expression capability. My own

perference would have been for coverage of these two languages over the

the three chosen by the author.

There is a chapter on solving practical problems but I would have preferred even more on this topic. Little mention is made of utilities

such as sed that depend entirely on regular expressions for their usefulness.

To the author's credit, he does document carefully many of the traps into

which regular expression programmers frequently fall.

Many consider regular expressions to be inelegant but they are

much more concise than the alternatives and are often used where there

is no other reasonable choice. If you find yourself in this situation,

and especially if you are using regular expressions in more than one

language or utility, you will benefit from reading this book. It is

well organized and readable.

Larry Bezeau

University of New Brunswick