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The Python Cookbook
Beautiful plumage. O'Reilly, fortunately, has all kinds of experience with animals.
The Python Cookbook consists of seventeen chapters that contain between eight and twenty-six individual recipes. Chapters and recipes are roughly ordered by increasing complexity, length, and required background knowledge, starting with the simple "Swapping Values Without Using a Temporary Variable" and ending with the complete module "Parsing a String into a Date/Time Object Portably." The chapters are mostly organized by subject -- "Text," "Files," "Object-Orientated Programming," "User Interfaces" -- but also include "Python Shortcuts" and "System Administration." The background required varies: Whereas the chapter on "Text" starts off with Fred L. Drake reviewing the most basic string operations such as slicing and concatenation, Paul F. Dubois can only sketch the core concepts of lexing and parsing in "Programs About Programs."
This of course is a hallmark of all cookbooks, programming- or food-wise: Nobody will like everything, but everybody will like something. The worst fragmentation occurs, as expected, between examples of Python 1.5.2 and Python 2.2. Most recipes give preference to one version, and then point out how the problem could have been solved in the other version. This is more useful than the code that was written for all versions, because it gives a deeper insight into the changes that Python has gone through. The result is that after a few chapters, you start wondering why anybody in their right mind would keep using Python 1.5.2 instead of 2.2.* with its iterators, list comprehensions, new classes, and expanded module library.
Martelli and Ascher have done a good job balancing the different forms. Only one chapter struck me as lopsided: "System Administration", where ten of the sixteen recipes are Windows-only. Even though there is a good reason for this -- Microsoft's native administration tools just aren't like those provided with Unix -- the editors might want to rethink the selection of recipes in this chapter for future editions.
Generally helpful. The "Python Cookbook" has helped me in three ways. First, I found quite a lot of the examples themselves, especially those in the chapters "Python Shortcuts" and "Object-Orientated Programming" useful for everyday work. Second, reading more than 500 pages of peer-reviewed and well-commented code gave me a greater feeling for common idioms and constructs that are rare in this clarity in wild-type code. However, the book is strongest when more general principles of "Pythonic" programming are discussed, for example when Martelli demonstrates the merits of the "Look Before You Leap," "Easier to Ask Forgiveness than Permission," and "Homogenize Different Cases" methods.
My favorite recipe is Sebastien Keim's "Implementing a Ring Buffer," where an object carries a class deep in its bowels, and changes into this class in a rather cool Dr.-Jekyll-to-Mr.-Hyde transformation on the fly. The one recipe I found downright evil was "Sending HTML Mail," which should have been implemented as "Turning HTML Mail into Plain Text" with a note on how people who send HTML mail are going to be the first against the wall when the revolution comes. The best quote in the book comes from Tim Peters: "We read Knuth so you don't have to" -- Python's promise of programming power for the people, expressed in (dare I say it) a nutshell.
Conclusion:
I can recommend the "Python Cookbook" wholeheartedly to anyone who has passed into the advanced stage of language learning and is willing to actually sit down and work through the code. Anybody who is looking for a deeper understanding of Python, solutions to common coding problems, or starting points for their own projects will also profit. This book should have RedHat customers hammering at the gates of Raleigh, demanding the power of iterators and list comprehensions that their SuSE counterparts already enjoy by default; it demonstrates the superiority of Python 2.2.* over 1.5.2 in great detail.
Because of this, however, my guess is that 2.2.* will quickly replace 1.5.2, turning large parts of this book into historical footnotes in two years at the latest. This is no fault of O'Reilly's, but rather a current fact of Python life. The editors have done a good job of nailing the parrot, and until this Pythonic Norwegian Blue does the inevitable backflip, it should give its owner much pleasure.
You can purchase The Python Cookbook from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Oy!
'Twould be more delectable with Ram's Bladder Cup!
-PONA-
+that's funny...I don't FEEL tardy.+
I have to ask (given my Python illiteracy), does Python have built-ins for such an operation? Or is this just "how to implement an old trick" to "get your feet wet" with Python?
If my coffee is working correctly this morning, I'd assert that any language with an XOR-assign could accomplish this feat (with the added restriction that the vars be of the same size, or operations are performed iteratively on byte pointers).
Below is chapter 1 of my new C cookbook:
A ^= B;
B ^= A;
A ^= B;
Short chapter.
Actually, this is an undefined behavior in c and c++, and you'd do well not to rely on it doing what you expect.
bn.com has this book listed for $31.96. Get it from Amazon for $27.97
Save some money!
pyhton isn't special because it can do crap like that. you can do that in basic. or c. or ada. or assembly. whatever.
b = a + b;
a = b - a;
b = b - a;
there's a few ways to solve this problem, and using white-space agnostic languages to boot.