BKMSRGEX.RVW   970221
 
"Mastering Regular Expressions", Jeffrey E. F. Friedl, 1997, 1-56592-257-3,
U$29.95/C$42.95
%A   Jeffrey E. F. Friedl jfriedl@ora.com
%C   103 Morris Street, Suite A, Sebastopol, CA   95472
%D   1997
%G   1-56592-257-3
%I   O'Reilly & Associates, Inc.
%O   U$29.95/C$42.95 800-998-9938 707-829-0515 fax: 707-829-0104 nuts@ora.com
%P   368
%T   "Mastering Regular Expressions"
 
Novice DOS users tend to find out reasonably quickly that "*.*", when used as
an argument with the delete command, means "everything".  Intermediate users
will have found that "?????.exe" matches programs with filenames under six
characters long, and that "*." finds directories (since novices usually don't
give directory names extensions).  (When I sent him the first draft of this
review, Friedl and I argued back and forth over whether if you want to find a
file which has "LAN" somewhere in the name you need to use "?????LAN?????.*". 
He's right and I was wrong: that's wrong.  But both of us can remember some
system where it works.)  DOS wildcards, though, are only the crudest
approximation to the power of the algorithmic matching that can be done with
regular expressions most widely known in relation to UNIX and UNIX derived
applications.
 
As the author points out, documentation on regular expressions is abundant, but
not very good.  In addition, there are differences between the use of regular
expressions in different applications and different versions of the same
application.
 
Friedl provides a realistic, reliable, and very readable introduction and
overview of the topic.  The use of humour not only leavens the text, but
supports the concepts being addressed.  The material is comprehensive, and
covers differences in the use of regular expressions both in sections dealing
with specific functions, and in a separate chapter which details usage in awk,
Tcl, and emacs.  (Perl gets a chapter all to itself.)  Readers may pursue the
topic as they wish, of course, but Friedl's offer of mastery extends to a
chapter on *how* matching is done: the internals of regular expressions.
 
Definitely, a valuable addition to the UNIX bookshelf, and also of use to those
working with grep, awk, Perl and the like on other platforms.  Or in any
situation where regular expressions are used.
 
copyright Robert M. Slade, 1997   BKMSRGEX.RVW   970221

======================
roberts@decus.ca         rslade@vcn.bc.ca         slade@freenet.victoria.bc.ca
link to virus, book info at http://www.freenet.victoria.bc.ca/techrev/rms.html
Author "Robert Slade's Guide to Computer Viruses" 0-387-94663-2 (800-SPRINGER)