🌐 Mailman 3 July 2007 - Python-list - python.org

encode() question
by 7stud Aug. 6, 2007

Aug. 6, 2007

s1 = "hello" s2 = s1.encode("utf-8") s1 = "an accented 'e': \xc3\xa9" s2 = s1.encode("utf-8") The last line produces the error: --- Traceback (most recent call last): File "test1.py", line 6, in ? s2 = s1.encode("utf-8") UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 17: ordinal not in range(128) --- The error is a "decode" error, and as far as I can tell, decoding happens when you convert a regular string to a unicode string. So, is there an implicit conversion taking place from s1 to a unicode string before encode() is called? By what mechanism?

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Live editing...
by kirby.urner＠gmail.com Aug. 5, 2007

Aug. 5, 2007

There's been some chatter on edu-sig (python.org) of late regarding Python's capabilities in the "edit/continue" tradition, meaning debugging tools, and/or IDE tools, that give the developer real time write access to running programs. I think a good design would be something like the ZODB, or the ZODB itself, to save the entire working environment, like a Smalltalk image, at which point a "supervisor Python" (a whole different instance, perhaps on another chip), could do "brain surgery" on the "hibernating Python" (like a patient undergoing surgery). You basically simulate or emulate the "operating table" version, without putting yourself at its mercy. If you break it completely, while doing your brain surgery, just abort the instance and roll back to the previously saved version. It's like sitting on top of a version control system, while never getting to directly edit the currently operating version (the supervisor). The alternative, allowing a developer to undermine his/her own running platform, seems to unnecessarily conflate a runtime and design time mode, which isn't just some stupid prejudice. We need that separation, just as we keep distance between production and development copies of things. Don't fix a running engine if you can fix an emulated running engine. Once you're happy with your changes, commit, and set it running for real. It still might crash, which is why you're glad for rollback capabilities. Smalltalk images meet CVS? Python atop Mercurial? Kirby

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Re: replacement for execfile
by Steven D'Aprano Aug. 3, 2007

Aug. 3, 2007

On Sat, 28 Jul 2007 15:17:56 +0000, Alex Popescu wrote: > Hi all! > > From another thread (and the pointed PEP) I have found that execfile > will not be present in Py3k. So, I am wondering what will be its > replacement? Considering that most probably Py3k will keep eval and > exec, this will still be possible (indeed requiring manual loading of > the file string), so I would really appreciate some enlightning comments > on this. (1) Don't use eval, exec or execfile. (2) If you're an expert, don't use eval, exec or execfile. (3) If you're an expert, and are fully aware of the security risks, don't use eval, exec or execfile. (4) If you're an expert, and are fully aware of the security risks, and have a task that can only be solved by using eval, exec or execfile, find another solution. (5) If there really is no other solution, you haven't looked hard enough. (6) If you've looked REALLY hard, and can't find another solution, AND you're an expert and are fully aware of the security risks, THEN you can think about using eval, exec or execfile. > Background: > Basically this question is related to my learning process/working > project. In this, I have the need to allow the final user to provide a > configuration like script, but built using my API (and whatever other > normal Python code they want). I hope this is running on their own computer, not yours. If they're running it on a multi-user system, I hope they don't care about security, because they probably don't have any now. > For this, having execfile was a nice surprise Oh yes, I bet it was, in more ways than one. > as I was able to automatically expose the API (so the end user > doesn't need to bother about imports) and also easily execute it in the > context I wanted. Let's see that I understand you... you're expecting the users to write working Python code, but you think "import module" is too hard for them? Anyway, with all the disclaimers above, execfile is trivial: def execfile_(filename, globals_=None, locals_=None): if globals_ is None: globals_ = globals() if locals_ is None: locals_ = globals_ text = file(filename, 'r').read() exec text in globals_, locals_ -- Steven.

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File handle not being released by close
by bg_ie＠yahoo.com Aug. 3, 2007

Aug. 3, 2007

Hi, I'm in the process of writing some code and noticed a strange problem while doing so. I'm working with PythonWin 210 built for Python 2.5. I noticed the problem for the last py file processed by this script, where the concerned tmp file is only actually written to when PythonWin is closed. In other words, after I run this script, one of the generated tmp files has a size of 0kB. I then close PythonWin and it is then written to. I'm guessing the garbage collector is causing the file to be written, but shouldn't close do this? /Barry import os, time, string dir = 'c:\\temp1' def listAllFile(fileNames,dir,files): def f1(a,dir=dir): return os.path.join(dir,a) files2 = map(f1, files) fileNames.extend(files2) fileNames = [] os.path.walk(dir,listAllFile,fileNames) for fileName in fileNames: fileBeginning = os.path.splitext(fileName)[0] fileEnd = os.path.splitext(fileName)[1] if fileEnd == ".py": print fileName f=open(fileBeginning+".tmp", 'w') f.write("Hello") f.close

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[2.5] Reading a two-column file into an array?
by Gilles Ganault Aug. 2, 2007

Aug. 2, 2007

Hello I'm sure there's a much easier way to read a two-column, CSV file into an array, but I haven't found it in Google. Should I use the Array module instead? ========= a = [] i = 0 #item<TAB>item<CRLF> p = re.compile("^(.+)\t(.+)$") for line in textlines: m = p.search(line) if m: a[i,0] = m.group(1) a[i,1] = m.group(2) i = i + 1 for i in a.count: for j in 2: print a[i,j] ======= Thank you.

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Re: standalone process to interact with the web
by beginner Aug. 2, 2007

Aug. 2, 2007

On Jul 31, 1:11 pm, Steve Holden <st...(a)holdenweb.com> wrote: > beginner wrote: > > Hi Steve, > > > On Jul 31, 11:42 am, Steve Holden <st...(a)holdenweb.com> wrote: > >> beginner wrote: > >>> Hi Everyone, > >>> I am looking for a way to allow a standalone python process to easily > >>> interactive with a few web pages. It has to be able to easily receive > >>> requests from the web and post data to the web. > >>> I am thinking about implementing a standalone soap server, but I am > >>> not sure which library is good. > >>> Any suggestions? > >>> Thanks a lot, > >>> Geoffrey > >> Look nor further than mechanize - > > >> http://wwwsearch.sourceforge.net/mechanize/ > > >> With mechanize and its partner ClientForm you can rule the web world ;-) > > >> regards > >> Steve > >> -- > >> Steve Holden +1 571 484 6266 +1 800 494 3119 > >> Holden Web LLC/Ltd http://www.holdenweb.com > >> Skype: holdenweb http://del.icio.us/steve.holden > >> --------------- Asciimercial ------------------ > >> Get on the web: Blog, lens and tag the Internet > >> Many services currently offer free registration > >> ----------- Thank You for Reading ------------- > > > This seems to be an HTTP client library. It is very interesting, but > > is not what I need. I am looking for something that can provide > > service to web pages. For example, when a browser requests a web page, > > the web page is going to send a few requests to my server. My server > > then is going to respond, and the web page takes the response and > > format it in human readable form. > > Well, surely in that case you can use any protocol you like. It's up to > the web server and your "web server server" to agree how to communicate. > Take a look at the SocketServer library, for example. > > regartds > Steve > -- > Steve Holden +1 571 484 6266 +1 800 494 3119 > Holden Web LLC/Ltd http://www.holdenweb.com > Skype: holdenweb http://del.icio.us/steve.holden > --------------- Asciimercial ------------------ > Get on the web: Blog, lens and tag the Internet > Many services currently offer free registration > ----------- Thank You for Reading -------------- Hide quoted text - > > - Show quoted text - Yes exactly. I just don't want to reinvent the wheel as I imagine there are already tons of libraries and frameworks that support RPC or the like functions. Thanks, Geoffrey

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standalone process to interact with the web
by beginner Aug. 2, 2007

Aug. 2, 2007

Hi Everyone, I am looking for a way to allow a standalone python process to easily interactive with a few web pages. It has to be able to easily receive requests from the web and post data to the web. I am thinking about implementing a standalone soap server, but I am not sure which library is good. Any suggestions? Thanks a lot, Geoffrey

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Wing IDE for Python v. 3.0 beta1 released
by Wingware Aug. 2, 2007

Aug. 2, 2007

Hi, I'm happy to announce the first beta release of Wing IDE 3.0. It is available from http://wingware.com/wingide/beta Wing IDE is a commercial IDE designed specifically for Python programmers. More information about the product and free trials are available at http://wingware.com/ The major new features introduced in Wing 3.0 are: * Multi-threaded debugger * Debug value tooltips in editor, debug probe, and interactive shell * Autocompletion in debug probe and interactive shell * Automatically updating project directories * Testing tool, currently supporting unittest derived tests (*) * OS Commands tool for executing and interacting with external commands (*) * Rewritten indentation analysis and conversion (*)'d items are available in Wing IDE Professional only. The CHANGELOG.txt file in the installation provides additional details. System requirements are Windows 2000 or later, OS X 10.3.9 or later for PPC or Intel (requires X11 Server), or a recent Linux system (either 32 or 64 bit). Reporting Bugs -------------- Please report bugs using the Submit Bug Report item in the Help menu or by emailing support at wingware dot com. This is beta quality software that installs side-by-side with Wing 2.x or 1.x. We advise you to make frequent backups of your work when using any pre-release version of Wing IDE. Upgrading --------- To upgrade a 2.x license or purchase a new 3.x license: Upgrade https://wingware.com/store/upgrade Purchase https://wingware.com/store/purchase Any 2.x license sold after May 2nd 2006 is free to upgrade; others cost 1/2 normal price to upgrade. Thanks! The Wingware Team Wingware | Python IDE Advancing Software Development www.wingware.com

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Re: Pythonic way for missing dict keys
by Steven D'Aprano Aug. 2, 2007

Aug. 2, 2007

On Sat, 28 Jul 2007 11:52:48 +0000, Alex Popescu wrote: > jjl(a)pobox.com (John J. Lee) wrote in news:87lkd0eprj.fsf@pobox.com: > >> Alex Popescu <nospam.themindstorm(a)gmail.com> writes: >> >>> Zentrader <zentraders(a)gmail.com> wrote in >>> news:1185041243.323915.161230 @x40g2000prg.googlegroups.com: >>> >>>> On Jul 21, 7:48 am, Duncan Booth <duncan.bo...(a)invalid.invalid> >>>> wrote: >>>> >>>> [snip...] >>>> >>>> >>>>>From the 2.6 PEP #361 (looks like dict.has_key is deprecated) >>>> Python 3.0 compatability: ['compatibility'-->someone should use a >>>> spell-checker for 'official' releases] >>>> - warnings were added for the following builtins which no >>>> longer exist in 3.0: >>>> apply, callable, coerce, dict.has_key, execfile, >>>> reduce, >>>> reload >>>> >>> >>> I see... what that document doesn't describe is the alternatives to >>> be used. And I see in that list a couple of functions that are >>> probably used a lot nowadays (callable, reduce, etc.). >> >> callable and reduce are rarely used, at least in code I've seen. > > I thought G would be using that function a lot. Who or what is G? Guido? And which of the two functions mentioned is "that function"? callable()? Instead of doing: if callable(function): function() you should do: try: function() except TypeError: pass That should work for most uses of callable(), but isn't quite the same. (What if function() has side-effects, or is expensive, and you want to determine if it is callable, but not actually call it _now_?) > Also, what is the replacement of reduce? I think I remember seeing > somewhere that lists comprehension would be (but also remember the > advise that reduce will be quicker). No, a list comprehension isn't equivalent to reduce(). There is no replacement for reduce(). Guido has essentially done the functional equivalent of deciding that because he personally doesn't like for loops, they can and should be written out as: counter = 0 while counter < len(sequence): item = sequence[counter] do_something_with_item counter += 1 because it is "easier to read" than a for loop. And yes, if you think my example is extreme because nobody would be that stupid, that's the point: removing reduce() _is_ that stupid (and it is not often I say that about a language design decision by Guido!). Python can, and probably will, get away with it only because reducing an iterable to a single value is an uncommon operation, and the most common uses of it (summing a sequence, finding the minimum and maximum) already have workable replacements. It's especially stupid because map() and filter(), both of which do have simple, easy to understand, completely functional replacements, are going to stay. reduce() doesn't, and it is going. That's nuts. It's a shame really. Oh well, maybe it will sneak back in via a functional module, or itertools, or something. What a waste, what a waste. >> Certainly has_key will be >> the most common of those listed above (but trivial to fix). > > dict.has_key(key) becomes key in dict (correct?) Yes. >> apply >> will be common in old code from the time of Python 1.5.2. > > I think there were some advises to not use apply. help(apply) already tells you how to replace apply(): Deprecated since release 2.3. Instead, use the extended call syntax: function(*args, **keywords). >> execfile is >> perhaps more common that callable (?) but again is really a "maybe 1 >> call in a big program" sort of thing. > > What is the replacement for this one? Slurp the file into a string, execute the string. But the thing that makes my brain melt is reload(). No, reload() probably isn't good enough to use in production code, but for interactive use it is Good Enough. I'm boggled that it is going away! -- Steven.

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Error with Tkinter and tkMessageBox
by Fabio Z Tessitore Aug. 2, 2007

Aug. 2, 2007

hi all, this Tkinter very simple code work fine: ########################## from Tkinter import * win = Tk() win.mainloop() ########################## but if I try to open a message box, it happens: Exception in Tkinter callback Traceback (most recent call last): File "lib-tk/Tkinter.py", line 1348, in __call__ return self.func(*args) File "/home/fabio/Desktop/prova.py", line 5, in reply showinfo(title='ciao', message='hello') File "lib-tk/tkMessageBox.py", line 84, in showinfo return _show(title, message, INFO, OK, **options) File "lib-tk/tkMessageBox.py", line 75, in _show res = Message(**options).show() File "lib-tk/tkCommonDialog.py", line 52, in show s = w.tk.call(self.command, *w._options(self.options)) TclError: bad pad value "2m": must be positive screen distance ############################## from Tkinter import * from tkMessageBox import * def reply(): showinfo(title='ciao', message='hello') win = Tk() but = Button(win, text='press me', command=reply) but.pack() win.mainloop() ############################## these are versions: python: 2.4.4 or 2.5.1 Tkinter.TclVersion: 8.4 Tkinter.TkVersion: 8.4 can anyone help me? thanks

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