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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.
The title "Python Cookbook" has gotta look weird to people bopping around Barnes & Noble who aren't in the know. :)
/*drunk.. fix later*/
And for those of you that can't get your hands on a python, the adder, asp, boa, cobra, diamondback, etc cookbooks are just as well packed with tasty recipes.
"Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
Cornmeal Crusted Rattle Snake with Cactus-Corn Succotash
Recipe courtesy Joey Altman, Copyright 2001
2 1/2 pounds rattle snake, dead
1 cup buttermilk
1 cup cornmeal
1 cup flour
1 tablespoon salt
1 tablespoon chile powder
1 tablespoon garlic powder
1 tablespoon paprika
1 teaspoon cayenne pepper
1 teaspoon ground cumin
1 cup vegetable oil
Cactus-Corn Succotash, recipe follows
Using a sharp boning knife remove the meat from the snake by cutting down the back, just slightly to 1 side of the spine from the head to the rattle. Using the tip of the knife peel the meat from the ?rib cage?. Once you removed the 2 long strips of meat, lightly pound them with the back of the knife to tenderize them. Cut the strips of meat into 1-inch pieces and place in a bowl with the buttermilk. Mix to coat well. In a large bowl combine the cornmeal with the flour and the spices. Heat the oil in a large skillet on medium high heat. Dredge the snake pieces in the flour mixture and fry for 2 minutes or until golden brown and then transfer to a paper towel lined plate. Repeat until all the snake pieces are cooked. Serve with Cactus-Corn Succotash.
Cactus-corn succotash:
2 tablespoons olive oil
1 cactus pad, thorns scraped off, cut into small dice
2 ears corn, shucked
1 red onion, peeled, sliced in rings, grilled with olive oil and chopped in small dice
1 bunch scallions, grilled and chopped
1 chayote squash, sliced 1/4-inch thick, grilled with olive oil and chopped in small dice
1 tablespoon minced garlic
2 tablespoons minced jalape?o
1/2 cup diced red bell pepper
4 tablespoons butter
1 cup chicken stock
1 cup diced, peeled and seeded tomatoes
1/2 cup chopped cilantro
Salt and pepper
Grilling the vegetables first gives another great layer of flavor, however, it is not absolutely necessary. Just omit that step and cook the vegetable right in the pan. In a skillet on high heat saute the vegetables except the tomatoes in the olive oil for 2 minutes. Add the stock and butter and cook until mixture reduces by half. Add tomatoes and seasoning and serve with the warm snake ?nuggets? on top.
Yield: 4 servings
Prep Time: 30 minutes
Cook Time: 10 minutes
Difficulty: Medium
There are those out there that hate any language that allows spaces to effect it's running...
But Python just rocks. Throw pySQL, wxPython and Twisted into the mix, and you can have a full blown server with gui front-end that is just as stable as any other. I have a server that I wrote for wireless devices performing a few hundred SQL queries/changes and file writes per hour, and the speed is surprisingly very good for a language most people refer to as a 'script'.
Not to mention, the tab requirement makes reading the code so easy. You just know where functions begin and end without having to deal with {'s and }'s.
RedHat 7.3 infamously still ships with version 1.5.2 as the default, while SuSE 8.0 is hanging in there with version 2.2
Debian unstable also has 2.2 as the default python, although the stable release has 2.1. But with the huge number of packages which depend on it, it takes a while to migrate all of them. So testing still has 2.1.
Some sort of snake, perhaps...
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It would be very instructive to me to be able to see how the two languages handle each other's idioms. I have my brain wrapped around perl and when I try to think in python I get frustrated cause things I think should be simple aren't. Of course the reverse would be true if I knew python better (I guess).
At present I think my python programming is too formal, like someone who just learned say french trying to speak it and saying "To The beloved person who bore me onto this earth; please to be informed that I have translocated my corpus into the domicale that lies here" instead of just saying "mom, I'm home".
Some drink at the fountain of knowledge. Others just gargle.
a,b = b,a
The perfect companion piece to Bake a Snake.
daed si luap
Much more to the point, Red Hat 7.3 has 1.5.2 as "python", but has 2.1 (IIRC) as "python2". And Red Hat 8 has 2.2.1 as its "python". And, as you said, it is eminently possible to download and compile the latest version, though you do have to be careful that you link in 2.2.x as "python2" rather than "python" on Red Hat 7.3, or many of the system apps break (up2date comes to mind...).
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.
Of course, installing a new version of Python in RedHat is pretty painless, download the rpm and install it. You can find them here.
"It's a very tangled subsystem." --Windows kernel guru
I used to code in Python, and now I use Ruby in it's place. I've found it to be just as readable but more terse. It's also extremely consistent in the way that everything is an object. You can say things like
5.times {|n| puts n}
and all kinds of other crazy things. I'm not saying it's better than Python(not trying to start a flame war). I'm just saying to try it and see if you like it.
A musician without the RIAA, is like a fish without a bicycle.
Try this site.. it's basically a "phrasebook" that shows common tasks being done in both perl and python. It's a great introduction to the language, and it helps a lot in terms of getting the python-idiom-y ways to do lots of commonthings embedded into your head.
:))
It isn't *very* long, and doesn't go too deep, and the formatting's not great, but it's a quick read, and if it doesn't fit your needs there's always that book Snowbike recommended.
At present I think my python programming is too formal
The catch about the funkiness of python's syntax is not that it demands formalism; it's just that it demands you will do only one thing per line. It's kind of hard to get yourself thinking this way, and it's really irritating to write code this way (i never write python without pining for a ?: construct, a single-line version of "except", or a less-crippled lambda construct).
The thing is, though, that obeying python's rule basically comes down to seperating each expression into unnecessary variables, and mercilessly abstracting all those potentially-repeated 'common tasks' that somehow always seem to wind up taking five lines in python into functions. However, i find when i write perl, most of the time i spend revising code is spent going back and doing the above two things-- splitting overly-complex expressions into subvariables, pulling out bits of code and making them subexpressions. Python just forces you to do these things ahead of time, and you benefit greatly in the long run. (Whether that's worth all the irritation, though, i don't know
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
No no he's not dead, he's, he's restin'! Remarkable bird, the Norwegian Blue, idn'it, ay? Beautiful plumage!
The author of this article doesn't mention it, but many Python programmers are upset with the rapid changes in the language, and it is very contrary to Python's history and philosophy. It looks like for now though, Python is slowing back down after implementing a new system of object orientation that really implements each variable/function/whatnot as an object. 2.2, hopefully, is here to stay for a while.
-- Ken Kinder ken@_nospam_kenkinder.com http://kenkinder.com/
Yeah, like the guy who drew Tux, whatshisname..
Escher was the first MC and Giger invented the HR department.
HTML email is not just for spammers.
.
No; it's also for people who want me to want a half hour to get my mail over my modem, so I can get the exact same message but with lots of HTML tags. (And invariablly lots of HTML tags - it never bears any resemblence to clean hand-written HTML.)
The ability to send HTML forms to employees is a boon among other benefits.
And what happens when you need to make a change to that form? Why not just stick it your own private webspace?
Maybe you've never shared the joy of sending an HTML birthday card to your child or parent.
Ah, yes; the wonderous feeling of "you crossed my mind, but I couldn't be bothered to walk to the store for a _real_ birthday card".
It's a little more valid, but it's still something that can be done via web.
The ability to communicate with the richness of HTML expression
To be or not to be; that is the question. Whether 'tis greater to suffer the slings and arrows of outrageous fortunes, or by dying, end them. . .
I fail to see how this could be made richer by adding HTML. In general, just straight plain text is an extraordinarily powerful medium for communication. Frequently, HTML seems to be used as a means to doodle on the email, rather then add any information or emotional empact.
Rather than a new topic for Python, I'd rather see a Scripting topic. So, yeah, that means no cute Python icon, but it does put all the scripting issues in one place for people to select or ignore.
Aside from the point about lack of declaration of variables, you're points against Python all reduce down to syntax issues.
It's a good thing you posted AC. I wouldn't want to take credit for that dreck either.
Oh, and if Python were only two years old, then I wouldn't have been able to do the Python project I did for a client when I did.
Have you even used Python? I didn't think so. I guess that if you want to be cynical and condescending about a language just because you're a self-appointed language guru, then please go ahead. But I think we would all prefer that you keep your opinion under wraps until it is informed and rational.
Please mod this post only if you think others should/n't read this. I have enough ego^H^H^Hkarma. Thanks!