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Python 2.3 Final Released
An anonymous reader writes "Nineteen months in the making, Python 2.3 has just been released. With a plethora of changes since version 2.2, this release is definately worth the upgrade. Be sure to read the Release Notes and the Highlights file for more information."
In 3... 2... 1...
Wow, finally Python 3! Are they as good as the original Monty Python? I didn't see the second Monty Python...Err... Is John Cleese still in Python?
I'm just waiting
for the trolls to start
complaing about
whitespace usage in
Python.
That, and what does this mean for improvments to my favourite distro's package management? (Gentoo!)
At the top of the list of new features they have sets. The first paragraph says that sets are implemented by hashtables. I wonder whether it is really meaningless from the "practical" point of view to implement sets with data structures like red-black trees or Fibonacci heaps. The advantage of the latter over hashtables is a solid bound on the worst case running times.
Ask any Python aficionado and you'll hear that Python programmers have it all: an elegant language that offers object-oriented programming support, a readable, maintainable syntax, integration with C components, and an enormous collection of precoded standard library and extension modules. Moreover, Python is easy to learn but powerful enough to take on the most ambitious programming challenges. But what Python programmers have lacked is one concise and clear reference resource, with the appropriate measure of guidance in how best to use Python's great power. Now Python in a Nutshell fills this need.
:)
In the tradition of O'Reilly's "In a Nutshell" series, this book offers Python programmers one place to look when they need help remembering or deciphering the syntax of this open source language and its many modules. This comprehensive reference guide makes it easy to look up all the most frequently needed information--not just about the Python language itself, but also the most frequently used parts of the standard library and the most important third-party extensions.
Python in a Nutshell focuses on Python 2.2 (and all its point releases), currently the most stable and widespread Python release. This book includes:
A fast-paced tutorial on the syntax of the Python language itself
An explanation of object-oriented programming in Python, covering both the classic and new-style object models
Coverage of other core topics, including exceptions, modules, strings, and regular expressions
A quick reference for Python's built-in types and functions, as well as the key modules in the Python standard library, including sys, os, time, thread, math, and socket, among many others
Reference material on important third-party extensions, such as Numeric and Tkinter
Information about extending Python and embedding it into other applications
Python in a Nutshell provides a solid, no-nonsense quick reference to information that programmers rely on the most. This latest addition to the best-selling "In a Nutshell" series will immediately earn its place in any Python programmer's library.
Synopsis
In the tradition of O'Reilly's "In a Nutshell" series, this book offers Python programmers help remembering or deciphering the syntax of this open source language and its many modules. This comprehensive reference guide should make it easy to look up all the most frequently needed information - not just about the Python language itself, but also the most frequently used parts of the standard library and the most important third-party extensions. The book includes: a fast-paced tutorial on the syntax of the Python language itself; an explanation of object-oriented programming in Python, covering both the classic and new-style object models; coverage of other core topics, including exceptions, modules, strings, and regular expressions; a quick reference for Python's built-in types and functions, as well as the key modules in the Python standard library, including sys, os, time, thread, math, and socket, among many others; reference material on important third-party extensions, such as Numeric and Tkinter; and information about extending Python and embedding it into other applications.
Happy?
I have over 70 freaks, do you?
Check out Artima if you want to see Bruce Eckel's take on the Python language which, incidentally, with the addition of things like a logging API, and with long-existing additions like Jython, is beginning to look more and more like a viable competitor to Java.
Why?
Python carries a LOT of the same advantages, but with a dramatically accelerated prototyping and general development speed, and a few tricks of its own. Plus, via Boost, it interoperates with C++, too. I'm an avid Perl hack, but I have to admit that Python, which even has a whole API for basic game programming is looking more and more attractive for quite a number of things.
Download soon and often.
Chr0m0Dr0m!C
According to a couple of simple benchmark, Python 2.3 is about 20-30% faster than Python 2.2.3. Some of this speed-up was obtained by removing the SET_LINENO opcodes, which means that the difference is less impressive when comparing "python -O"; the rest was various careful tune-ups.
This is a big improvement. The biggest advantage of using a programming langage like python is the fast development time (5X-10X faster than C++). If the speed of execution of python scripts can be made comparable to compiled C/C++ code, then it would be awesome. Python programs can never be as fast as compiled code, but if the difference in the speed is not significant, it will be a big win for Python
He's a troll. "Fu-Ling Yu" Get it? Haha and all that. He just pastes some links from the quoted article and get modded +5 with alacrity because of his charming "engrish". The stupid mods always fall for it.
I've been learning Python Language for a while, but since I don't work with other programmers, it's taken me quite a while. I learned python the usual way (a mix between the on-line tutorial and Learning Python) and my fluency is improving.
I picked up this book recently while I was at a convention in Baltimore. I liked its organization: the book features a whole chapter on each datatype (strings, numbers, tuples, lists, and dictionaries). There are also chapters on Control Flow Statements, Functions, Modules, Files, Classes, and Exceptions.
Because of its organization, it's as useful as a reference as it is a tutorial. Each chapter contains progressively advanced examples that end up demonstrating the finer points of each topic.
For example, one hint was to use the vars() function creates a dictionary of the local namespace. This makes it useful when string formatting:The book does not cover advanced topics like Tkinter, Jython, or extending Python with C. Nor does it cover the Library modules (the Python online documentation is actually quite good).
"Python" is newer, cheaper (22 USD vs. 30 USD), and longer (410pp vs. 368pp) than "Learning Python"
I would recommend this book to anyone who would like to learn Python. If you're an intermediate Pythoneer, I agree with the parent: you will want to get "Python In A Nutshell".
My father is a blogger.
I hear this repeated fairly often, but I can not think of any really good reason why whitespace is bad. IMHO, any decent programmer worth his/her salt will whitespace their code anyway for sanity.
Just to be my own devil's advocate, here are some reasons I can think of off the top of my head. But I don't think any is sufficiently great for not using python strictly because of it's required whitespace syntax.
Actually, I want to become proficient in python, I've even got a few books, and just haven't gotten around to programming any application in it yet :-( But these are things I've wondered about (regarding the whitespace). Hopefully a seasoned veteran can point out why these aren't substantial problems.
- Putting a large block of code into a while or for loop.
-
TABS and order of whitespace
- For decently-complex programs there might be so many nesting levels that the indented code is spaced so far inwards that one needs ridiculously-wide displays for sanity.
Other than those rare or obscure issues, I can't think of any reason that mandatory whitespacing should hold someone back from python.In C, if I am quickly hacking some stuff together and realize I want to put 100+ lines into a for loop, I can put brackets around the code and possibly indent it later if I wind up keeping the code for long-term.
In python I'd have to manually go to all those lines and put the indent in. (I assume EMACS and other editors can do this automatically, if one knows the key combinations).
This confuses me. Does python keep track of instances of \t in an input file? Are they distinguishable from spaces? If at some nested level of indentation I'm at [tab][space][space], is a line of indentation of [space][space][tab] at the same nesting level?
If I'm at [space][space][space][space] can the next level of nesting be [tab]?
Personally, I don't think I've ever put more than 10 levels of nested blocks in a program somewhere, but I suppose it could possibly happen and might be a problem, especially of someone is restricted to 80-column screen for some reason.
make world, not war
Isn't that better?
No cookie for you.
It could be worse, people could be learning Basic instead of Pascal and Java. At least they are slightly similar to C. I start programming with Basic and it's haunted me ever since.
For your second point, 10 levels of nesting is, IMHO, at least 7 too many. That's what subroutines are for. If you find yourself adding another level after three, it's probably time to look at your design.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
Discussions on tabs and spaces can lead to flamewars in Python circles. Many people hate tabs, and a significant majority of code does not use tabs.
As far as screen width, that's no different in Python than any other language. Deep nesting is a sign of a program in need of refactoring.
Alex Martelli has indeed written an excellent book. Actually, he almost wrote two excellent ones, since he is co-editor of _Python Cookbook_ too (but the latter is really more of a collaboration of dozens of people in the Python community than a book by an individual).
However, my book, _Text Processing in Python_, has at least one think over Alex's that is germane to this thread: I make a good effort to cover Python 2.3. I am quite confident that mine is the only book you can actually buy today that does so (I'm sure there will be more titles, and various updates, over time, of course). Don't let my title fool you, btw, I do a bit more than the title entirely admits to. But the title isn't a lie either, it really is focussed on the broad area called "text processing".
Anyway, there's nothing subtle in my plug. I really will get a couple dollars every time someone buys one (unlike the somewhat odd insinuation downthread about Sir Haxalot doing so). But then, I also invite everyone to read the entire text for free at:
http://gnosis.cx/TPiP/
So you can have something for nothing too, if you want.
David Mertz
Buy Text Processing in Python
The reason I never bothered with Python is because of the whitespace issue, and I'll tell you why:
I don't trust that blocks are properly grouped.
When I program in C++, Java or even Ruby, and I create a new block, the first thing I do is close the block. Any code I put in the block I indent, but if the block grows, or my indenting gets goofy, I don't have to fear that my block is now improperly closing.
If I paste in a few quick lines of code for debug purposes, and it just happened to be indented differently than where I was pasting it, that would screw up the block closure unless I went and tabbed everything correctly. Sometimes, I *like* that the temporary code is indented wrong because it helps remind me to comment it out or remove it when I'm done debugging.
The whitespace thing is just too weird. It generates a lot of feelings that I might screw up my blocks. That sort of anxiety shouldn't be there; I shouldn't be so worried about blocks closing.
Actually, it could. The PHP crowd blew every horn they could find when yahoo switched over to PHP, but AOL has been using python behind the scenes for a long time with little fanfare (or problems). So if it's AOL doing the upgrading, it might help your AOL downloads be faster.
Do you even lift?
These aren't the 'roids you're looking for.
For simple flags, yes, "1" is quicker to type than "True". But Booleans can make other kinds of code clearer:
"For example, if you're reading a function and encounter the statement return 1, you might wonder whether the 1 represents a Boolean truth value, an index, or a coefficient that multiplies some other quantity. If the statement is return True, however, the meaning of the return value is quite clear."
your new hear, i take it.
we definately do not waist are time with speling and grammer, you looser.
in the immortal words of homer*:
"if i spelled cat 'C', 'A', 'T', you'd know what i mean"
* simpson, homer j. not that other guy.
Haunted? Leave it to dearly departed Edsger Dijkstra to say how it really is:
``It is practically imposible to teach good programming to students that have had a prior exposure to BASIC: as potential programmers they are mentally mutilated beyond hope of regeneration.''
"My fingers Emit sparks of fire in Expectation of my future labours." William Blake
This guy is a TROLL people. All the others calling his bluff got modded into oblivion. Read some of them, and/or take a quick look at this dudes posting history. I've given up the -1 mod I had used to point this out instead, karma be damned. Anyone who makes a hobby of publicly mocking other racial groups while hiding behind an internet connection deserves to be called out.
"Gold still represents the ultimate form of payment in the world." - Alan Greenspan, 1999
The new introspection facilities introduced in version 2.2 allow one to go around Bastion and rexec restrictions.
Python is definitely not typeless. It's actually strongly typed. But it uses dynamic typing.
Take a look at this article for clarification on typing models.
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
list[-1] is the last item in the list. To anyone coming from a functional programming background (such as lisp), the head of the list is the first element and the tail is everything else.
Lisp style cons lists are essentially a big nested set of tuples
[1, 2, 3, 4, 5]
translates to
(1, (2, (3, (4, (5, _)))))
so head (the lisp CAR) is the first element of this two item tuple, tail (lisp's CDR) is the 2nd element, or the rest of the list.
my sig's at the bottom of the page.