🌐 Mailman 3 August 2006 - Python-list - python.org

Re: Nested function scope problem
by Antoon Pardon Aug. 2, 2006

Aug. 2, 2006

On 2006-08-02, Dennis Lee Bieber <wlfraed(a)ix.netcom.com> wrote: > On 1 Aug 2006 17:44:54 GMT, Antoon Pardon <apardon(a)forel.vub.ac.be> > declaimed the following in comp.lang.python: > >> Suppose I write a C-interpreter and then would translate a statement >> like "c = c + 100" into actions the interpreter would have to take in >> order to excute that statement. Something like: >> >> c-addr_p = GetAddress("c"); >> c-value = *c-addr_p; >> sum = c-value + 100; >> *c-addr_p = sum; >> > If this is what your interpreter generates/executes for a C-language > assignment, then the source language is no longer C... How do you come to that decision? > After all, Python's most common implementation IS in C. > > In C, the difference between "c" as a pointer, and "*c" as what it > points to is explicitly exposed to the user... The two views can be > separately manipulated. "c" as a variable can be manipulated -- c++ > changes c to "point to" an object (of the type of "c") that is presumed > to follow the existing object -- whether such exists or not. > > Python does not expose that to the user... You have a name and you > have an object. The name exists, or it doesn't, independent of the > object. Not in C -- while the object may not exist, the name, to be used > at all, has to exist and has storage space assigned to it; storage the > programmer is able to manipulate without an object. And how is this all relevant in deciding that the source language for the above interpreter actions isn't C? What the interpreter does is the following: Get the addres of the variable c Get the value that is at that address. Add 100 to this value Store the new value at that address. Please explain what is wrong in this sequence of actions for an interpretation of the C statement: "c = c + 100;" -- Antoon Pardon

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Re: Reinstalling Python Problem (Newbie)
by Avell Diroll Aug. 2, 2006

Aug. 2, 2006

beno wrote: > Avell Diroll wrote: >> beno wrote: >> *** tidying a little *** >>> >>> What do I do about the problems with mimetools and urllib2? >>> >> >> This is the last report of the 'make test' command and there should be >> a few lines before that stating each test one by one and printing >> problems has they appear, and sometime pointing at a possible source >> for the specific problem. Have you got such a report for test_urllib2 ? >> > Here it is for both: > > test_mimetools > test test_mimetools failed -- Traceback (most recent call last): > File "/usr/local/zope/py243/Lib/test/test_mimetools.py", line 30, in > test_boundary > nb = mimetools.choose_boundary() > File "/usr/local/zope/py243/Lib/mimetools.py", line 130, in > choose_boundary > hostid = socket.gethostbyname(socket.gethostname()) > gaierror: (8, 'hostname nor servname provided, or not known') > > > test_urllib2 > test test_urllib2 failed -- Traceback (most recent call last): > File "/usr/local/zope/py243/Lib/test/test_urllib2.py", line 352, in > test_file > for url in [ > gaierror: (8, 'hostname nor servname provided, or not known') > > Looks like the same error ;) So, where am I supposed to provide this > servname? > >> *** tidying a little *** This gethostname() problem in the test suite looks like an old problem. I believe your problem is related to what Anthony Baxter and Guido van Rossum where discussing back in 2004 on the python-dev mailing list : http://mail.python.org/pipermail/python-dev/2003-November/040501.html To put things short the test suite might fail on any test using socket.gethostname() on a machine where /etc/hostname and /etc/hosts are not matching. If that is the case for your machine, the problem is coming from the test suite, not your python build. regards, Avell

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Datetime objects
by Lad Aug. 2, 2006

Aug. 2, 2006

How can I find days and minutes difference between two datetime objects? For example If I have b=datetime.datetime(2006, 8, 2, 8, 57, 28, 687000) a=datetime.datetime(2006, 8, 1, 18, 19, 45, 765000) Thank you for help L.

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Re: Behavior on non definded name in Cheetah
by Stephan Diehl Aug. 2, 2006

Aug. 2, 2006

Paolo Pantaleo wrote: > [I hope I am posting to the right place] > > I have a cheetah template something like this: > > x is: $x > y is: $y > z is: $z > > [Actually more complicated] > > If for example $y is not defined I get an exception and the parsing > of the template stops. Is there any way to substitute $y with an emty > string and making cheeta going on with parsing? > > Thnx > PAolo > http://cheetahtemplate.org/docs/users_guide_html_multipage/language.namemap…

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Attribute protection the 2nd
by Kay Schluehr Aug. 2, 2006

Aug. 2, 2006

A new recipe for attribute protection which is aligned with Pythons convention of privacy indication using underscore name mangling. http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/496930 Regards, Kay

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Behavior on non definded name in Cheetah
by Paolo Pantaleo Aug. 2, 2006

Aug. 2, 2006

[I hope I am posting to the right place] I have a cheetah template something like this: x is: $x y is: $y z is: $z [Actually more complicated] If for example $y is not defined I get an exception and the parsing of the template stops. Is there any way to substitute $y with an emty string and making cheeta going on with parsing? Thnx PAolo -- if you have a minute to spend please visit my photogrphy site: http://mypic.co.nr

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Re: Using Python for my web site
by Conrad Aug. 2, 2006

Aug. 2, 2006

On Mon, 31 Jul 2006 17:12:56 -0300, Gerhard Fiedler wrote: > On 2006-07-31 15:00:15, Bruno Desthuilliers wrote: > >> In fact, the real question IMHO is: what would MySQL advantage over >> PostgreSQL be ?-) > > A few years ago I did some research, and the result was that while > PostgreSQL was claimed to have more features and a better design, the > reports of database corruption seemed to have been more frequent than with > MySQL. The usual reason given was that MySQL was more mature. > > I assume you don't agree... :) > > Gerhard Maturity is an interesting word. The PostgreSQL pedigree reaches back about thirty years, which in some peoples minds, would constitute a degree of maturity. While I can't claim to have done your extensive (and well documented) research, I can say that I was a happy MySQL user a couple of years ago, using it to quickly serve up fairly static content. Happy, that is, until I put it into a more dynamic order entry/processing environment. I started finding glitches - orphaned records - one table totally corrupted. I found I was spending more and more time coding to make sure the transactions completed, and less time developing new code. I switched that client to PostgreSQL and have had ZERO problems since. Many of the "features" that MySQL is only now adding are playing catchup to core data integrity values that PostgreSQL has had for much longer, so it could be argued that in some areas, MySQL can be said to be much less "mature".

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Re: Reinstalling Python Problem (Newbie)
by Avell Diroll Aug. 2, 2006

Aug. 2, 2006

beno wrote: > I intend to do that. However, I think this is the RIGHT list to ask > questions pertinent to python... I didn't intend to be abrupt, ... I was just in an hurry, sorry for that. Anyway I still see this problem more as a program not compiling correctly on Freebsd than python not compiling correctly on a platform ... everybody has his own point of view :-) Anyway I don't have any freebsd box around any more, so there is no way for me to reproduce your problem (hence my remark about the place to post). Another thing, if you just want to use zope, it seems to be included in freebsd ports ... so you should not need to compile anything to _run_ zope on your system, but maybe you need specific options not included in the ports (this is only fully supported on freebsd-stable and freebsd-current which are AFAIK respectively 6.1 and 7.). Ref.: http://www.freebsd.org/ports/zope.html http://www.freebsd.org/ports/lang.html#python-2.4.3 Zope is not supported in 5.5 anymore but it is present in the ports archive. ftp://ftp.freebsd.org/pub/FreeBSD/releases/i386/5.5-RELEASE/ports/ To get back to your specific problem : > 2 tests failed: > test_mimetools test_urllib2 > 48 tests skipped: > test_aepack test_al test_applesingle test_asynchat test_bsddb > test_bsddb3 test_cd test_cl test_codecmaps_cn test_codecmaps_hk > test_codecmaps_jp test_codecmaps_kr test_codecmaps_tw test_curses > test_doctest test_fork1 test_gdbm test_gl test_imgfile test_imp > test_linuxaudiodev test_logging test_macfs test_macostools > test_nis test_normalization test_ossaudiodev test_pep277 > test_plistlib test_queue test_scriptpackages test_socket > test_socket_ssl test_socketserver test_sunaudiodev test_tcl > test_thread test_threaded_import test_threadedtempfile > test_threading test_threading_local test_threadsignals > test_timeout test_unicode_file test_urllib2net test_urllibnet > test_winreg test_winsound > 13 skips unexpected on freebsd5: > test_threadedtempfile test_imp test_threaded_import test_fork1 > test_threading test_threadsignals test_socket test_thread > test_queue test_asynchat test_doctest test_threading_local > test_logging > *** Error code 1 > > What do I do about the problems with mimetools and urllib2? This is the last report of the 'make test' command and there should be a few lines before that stating each test one by one and printing problems has they appear, and sometime pointing at a possible source for the specific problem. Have you got such a report for test_urllib2 ? > What is meant by pointing to this folder thus (as the installation > instructions instruct): > ./configure --prefix=/usr/python The autotools (configure/make/make install) default installation directory is /usr/local by using the prefix option, you are indicating that you want to install all the python files in /usr/python when you will execute the command 'make install' (instead of /usr/local). I don't know which installation instructions you are following, but FWIK this is not a standard place for python to be installed (although it is recommended in the README for the AtheOS platform ...). > BTW, the modpython site is down! It was up when I sent my first mail, and it is up as I send this one. http://www.modpython.org/ > TIA, > beno > As I stated before I don't have any freebsd box to play with ... HTH Regards Avell

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Re: how to stop python
by victor Aug. 2, 2006

Aug. 2, 2006

or if u want explicit exit of program then use: import sys sys.exit(1) or raise SystemExit, 'message' Dan wrote: > bruce bedouglas at earthlink.net posted: > > > perl has the concept of "die". does python have anything > > similar. how can a python app be stopped? > > I see this sort of statement a lot in Perl: > open(FH, "myfile.txt") or die ("Could not open file"); > > I've no idea why you're asking for the Python equivalent to die, but if > it's for this sort of case, you don't need it. Usually in Python you > don't need to explicitly check for an error. The Python function will > raise an exception instead of returning an error code. If you want to > handle the error, enclose it in a try/except block. But if you just > want the program to abort with an error message so that you don't get > silent failure, it will happen automatically if you don't catch the > exception. So the equivalent Python example looks something like this: > fh = file("myfile.txt") > > If the file doesn't exist, and you don't catch the exception, you get > something like this: > $ ./foo.py > Traceback (most recent call last): > File "./foo.py", line 3, in ? > fh = file("myfile.txt") > IOError: [Errno 2] No such file or directory: 'myfile.txt' > > /Dan

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Re: Dr. Dobb's Python-URL! - weekly Python news and links (Aug 2)
by david_wahler＠bic.ky Aug. 2, 2006

Aug. 2, 2006

I'll be out of the office until approximately August 20th. If you have any questions, please email support(a)bic.ky. -- David Wahler

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