[issue25464] Tix HList header_exists should be "exist"
New submission from Rob Williscroft: The method header_exists of Tix HList raises: File "...\python3\lib\tkinter\tix.py", line 926, in header_exists return self.tk.call(self._w, 'header', 'exists', col) _tkinter.TclError: unknown option "exists". Must be cget, configure, create, delete, exist or size IOW the option should be "exist" not "exists". I've seen this on Windows with python 2.7 and 3.4 and Linux-Mint with 2.7.6. The current method "header_exists" doesn't seem to be referenced or documented anywhere. -- components: Tkinter files: Lib-tkinter-tix-header_exist.patch keywords: patch messages: 253357 nosy: rtw priority: normal severity: normal status: open title: Tix HList header_exists should be "exist" type: crash versions: Python 2.7, Python 3.4 Added file: http://bugs.python.org/file40842/Lib-tkinter-tix-header_exist.patch ___ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue25464> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
Re: Sending a broadcast message using raw sockets
Peter Steele wrote in news:0c2b3482-df46-4324-8bf9-2c45d3f6b...@googlegroups.com in comp.lang.python: On Monday, January 21, 2013 1:10:06 AM UTC-8, Rob Williscroft wrote: Peter Steele wrote in news:f37ccb35-8439-42cd-a063-962249b44...@googlegroups.com in comp.lang.python: I want to write a program in Python that sends a broadcast message [snip] This is part of my Wake-On-Lan script: def WOL_by_mac( mac, ip = 'broadcast', port = 9 ): [snip] Thanks for the code sample. Does this code work if the box has no IP or default route assigned? I'm away from the office at the moment so I can't test this. No idea, but the sockets system must be up and running before the card (interface) has an IP (otherwise how would it ever get assigned) and I presume DHCP works in a similar manner. However the route assignemt is irrelevent, broadcast messages never get routed. Rob -- -- http://mail.python.org/mailman/listinfo/python-list
Re: Sending a broadcast message using raw sockets
Peter Steele wrote in news:96947c45-f16b-4e97-b055-edc1241ee...@googlegroups.com in comp.lang.python: I just tried running you code, and the sendto call fails with Network is unreachable. That's what I expected, based on other tests I've done. That's why I was asking about how to do raw sockets, since tools like dhclient use raw sockets to do what they do. It can clearly be duplicated in Python, I just need to find some code samples on how to construct a raw packet. Try s = socket.socket( socket.AF_INET, socket.SOCK_RAW ) I tried this on windows and it needed admin privaleges to run. Rob. -- -- http://mail.python.org/mailman/listinfo/python-list
Re: Sending a broadcast message using raw sockets
Peter Steele wrote in news:f37ccb35-8439-42cd-a063-962249b44...@googlegroups.com in comp.lang.python: I want to write a program in Python that sends a broadcast message using raw sockets. The system where this program will run has no IP or default route defined, hence the reason I need to use a broadcast message. I've done some searches and found some bits and pieces about using raw sockets in Python, but I haven't been able to find an example that explains how to construct a broadcast message using raw sockets. Any pointers would be appreciated. This is part of my Wake-On-Lan script: def WOL_by_mac( mac, ip = 'broadcast', port = 9 ): import struct, socket a = mac.replace( ':', '-' ).split( '-' ) addr = struct.pack( 'B'*6, *[ int(_, 16) for _ in a ] ) msg = b'\xff' * 6 + addr * 16 s = socket.socket( socket.AF_INET, socket.SOCK_DGRAM ) s.setsockopt( socket.SOL_SOCKET, socket.SO_BROADCAST, 1 ) s.sendto( msg, ( ip, port ) ) s.close() The mac address is 6 pairs of hex digits seperated by '-' or ':'. http://en.wikipedia.org/wiki/Wake-on-LAN Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Conditional decoration
Roy Smith wrote in news:jro9cj$b44$1...@panix2.panix.com in gmane.comp.python.general: Is there any way to conditionally apply a decorator to a function? For example, in django, I want to be able to control, via a run-time config flag, if a view gets decorated with @login_required(). @login_required() def my_view(request): pass You need to create a decorator that calls either the original function or the decorated funtion, depending on your condition, Something like (untested): def conditional_login_required( f ): _login_required = login_required()(f) def decorated( request ): if condition == use-login: return _login_required( request ) else: return f( request ) return decorated @conditional_login_required def my_view(request): pass Replace (condition == use-login) with whatever your run-time control flag is. -- Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: ordering with duck typing in 3.1
andrew cooke wrote in news:33019705.1873.1333801405463.JavaMail.geo-discussion-forums@ynmm9 in gmane.comp.python.general: hi, please, what am i doing wrong here? the docs say http://docs.python.org/release/3.1.3/library/stdtypes.html#comparisons in general, __lt__() and __eq__() are sufficient, if you want the conventional meanings of the comparison operators but i am seeing assert 2 three E TypeError: unorderable types: int() IntVar() with this test: class IntVar(object): def __lt__(self, other): return self.value other so what am i missing? The part of the docs you are relying on uses the wording in general, IOW, it is not saying that defining __eq__ and __lt__ will always be sufficient. In this case the expression 2 three is calling int.__lt__, which doesn't know how to comapre to an instance of your class so returns NotImplemented. At this point if you had defined a __gt__ method the interpreter would then try and call that having first switched the arguments around. But you didn't so a TypeError is raised. I'm afraid I couldn't find anywhere in the docs where that behaviour is described, I suspect I only know it from lurking on usenet for a number of years. The best description that I could find of the behaviour you are seeing is at: http://docs.python.org/py3k/reference/expressions.html#not-in There is a paragraph that contains: ... the == and != operators always consider objects of different types to be unequal, while the , , = and = operators raise a TypeError when comparing objects of different types that do not implement these operators for the given pair of types. ... Perhapse the docs could be reworded to note that, to define a full set of comparisons between *different* types, you need to define a full set of special methods. Some links I found along the way: http://docs.python.org/release/3.1.3/library/constants.html? highlight=__lt__#NotImplemented http://code.activestate.com/recipes/576685/ http://docs.python.org/py3k/library/functools.html#functools.total_ordering Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Cannot connect to IMAP server in Python 3.2
Steven D'Aprano wrote in news:4f7d2475$0$3$c3e8...@news.astraweb.com in
gmane.comp.python.general:
I can connect to an IMAP server using Python 2.6:
steve@runes:~$ python2.6
Python 2.6.6 (r266:84292, Dec 27 2010, 00:02:40)
server = imaplib.IMAP4_SSL('x')
But when I try with Python 3.2, it just sits there until it times out:
server = imaplib.IMAP4('x', imaplib.IMAP4_SSL_PORT)
What am I doing wrong?
Not using IMAP4_SSL, above you are using IMAP4 (non SSL) but with the
SSL port.
http://docs.python.org/py3k//library/imaplib.html#imaplib.IMAP4_SSL
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Re: Returning a value from exec or a better solution
Jack Trades wrote in
news:CAG5udOh1+oE4g9Frjp3pucbHUtWcN34KK35a-Xs2YqkZH9X5=w...@mail.gmail.com
in gmane.comp.python.general:
def test():
src = (
def double(x):
return x * 2
)
globals = {}
exec( src, globals )
return globals[ double ]
print( test() )
I looked into doing it that way but it still requires that the user
use a specific name for the function they are defining. The docs on
exec say that an implementation may populate globals or locals with
whatever they want so that also rules out doing a simple for item in
globals, as there may be more than just the one function in there
(though I suppose I may be able to work around that).
Why not just get the name from the user, or use a regular expression
to extract the first (or last, maybe) definition from the source string.
Rob.
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Re: Returning a value from exec or a better solution
Jack Trades wrote in news:CAG5udOiOAge3uHrGSDTZ412GAg+CC- 6u8igoyj0lnf3hnwu...@mail.gmail.com in gmane.comp.python.general: class CapturingDict(dict): ... def __setitem__(self, key, val): ... self.key, self.val = key, val ... dict.__setitem__(self, key, val) ... c = CapturingDict() exec(def myfunction(x): return 1, c) c.key 'myfunction' c.val function myfunction at 0x100634d10 HTH, -- Arnaud That's brilliant and works flawlessly. Thank you very much! If an impementation (as you say up thread) can populate globals or locals with whatever they want, then how do you know that last item added was the function definition the user supplied ? Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Returning a value from exec or a better solution
Ethan Furman wrote in news:4e5d29c8.8010...@stoneleaf.us in gmane.comp.python.general: Jack Trades wrote: On Tue, Aug 30, 2011 at 2:37 AM, Rob Williscroft wrote: If an impementation (as you say up thread) can populate globals or locals with whatever they want, then how do you know that last item added was the function definition the user supplied ? Because the implementation will add things before the exec is processed. How do you know this ?, it isn't what the docs say. http://docs.python.org/reference/simple_stmts.html#the-exec-statement Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Returning a value from exec or a better solution
Arnaud Delobelle wrote in news:CAJ6cK1YVi3NQgdZOUdhAESf133pUkdazM1PkSP=p6xfayvo...@mail.gmail.com in gmane.comp.python.general: On 30 August 2011 13:31, Jack Trades jacktradespub...@gmail.com wrote: On Tue, Aug 30, 2011 at 2:37 AM, Rob Williscroft r...@rtw.me.uk wrote: That's brilliant and works flawlessly. ¶ÿThank you very much! If an impementation (as you say up thread) can populate globals or locals with whatever they want, then how do you know that last item added was the function definition the user supplied ? That's not an issue. The last statement that is executed will be the def statement. You don't know that, an implementation may for example set __bultins__ to None, prior to returning, its not an unreasonable thing to do and the docs don't say they can't. Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Returning a value from exec or a better solution
Jack Trades wrote in
news:CAG5udOg=GtFGPmTB=1ojnvnrpdyucxdokn1wjqmomv9gx0+...@mail.gmail.com
in gmane.comp.python.general:
... I wanted to allow the user to manually return the
function from the string, like this:
a = exec(
def double(x):
return x * 2
double
)
However it seems that exec does not return a value as it produces a
SyntaxError whenever I try to assign it.
def test():
src = (
def double(x):
return x * 2
)
globals = {}
exec( src, globals )
return globals[ double ]
print( test() )
The a bove works on 2.7 (I tested it) on earlier versions you may need
to use:
exec src in globals
Rob.
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Re: Button Label change on EVT_BUTTON in wxpython!!!
Ven wrote in news:aa1212bb-35e5-4bf9-b8ad-7a3c083749c2
@x2g2000yql.googlegroups.com in gmane.comp.python.general:
So, here is what I did/want:
self.run_button=wx.Button(self.panel,ID_RUN_BUTTON,label='Install')
self.Bind(wx.EVT_BUTTON, self.OnRun,id=ID_RUN_BUTTON)
def OnRun(self,evt):
self.run_button.SetLabel('Installing..')
#call a function that does the installation task
installation_task()
#After task completion, set the button label back to Install
self.run_button.SetLabel('Install')
When I try doing this, it doesn't set the label to Installing while
the task is being performed. Any suggestions how do I achieve this?
http://wiki.wxpython.org/CallAfter
Using this your OnRun will become somthing like:
def OnRun( self, evt ):
def after():
installation_task()
self.run_button.SetLabel('Install')
self.run_button.SetLabel('Installing..')
wx.Callafter( after )
However if installation_task takes a long time you will need to use
threads, something like (untested):
def OnRun( self, evt ):
def after():
self.run_button.SetLabel('Install')
def task():
installation_task()
wx.Callafter( after )
self.run_button.SetLabel('Installing..')
import threading
threading.Thread( target = task ).start()
Rob.
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Re: os.path.isdir do not work for Foder named '2011-07-03'
Nulpum wrote in news:0bf400a3-735c-487a-8d74- feb3b56be...@g5g2000prn.googlegroups.com in gmane.comp.python.general: I want to make sure that folder exists. '2011-07-03' is really exists. but 'os.path.isdir' say false Does anyone know why? os.path.isdir(C:\Users\Á¶Ã¢ÁØ\Desktop\logs) True os.path.isdir(C:\Users\Á¶Ã¢ÁØ\Desktop\logs\2011-07-03) False Maybe it isn't a directory, but a file, what does os.path.exists() return. Also could it be a Shortcut in which case 2011-07-03.lnk will exist. Also have you left Hide extensions for known file types switched on, in which case it may really be 2011-07-03.zip for example, a file not a directory even though Windows explorer shows it as a directory. -- Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: None versus MISSING sentinel -- request for design feedback
Steven D'Aprano wrote in news:4e1fd009$0$29986$c3e8da3 $54964...@news.astraweb.com in gmane.comp.python.general: I'm designing an API for some lightweight calculator-like statistics functions, such as mean, standard deviation, etc., and I want to support missing values. Missing values should be just ignored. E.g.: mean([1, 2, MISSING, 3]) = 6/3 = 2 rather than 6/4 or raising an error. If you can't make your mind up then maybe you shouldn't: MISSING = MissingObject() def mean( sequence, missing = MISSING ): ... Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Addition problems
vm wrote in news:in4m1u$hsc$1...@news2.carnet.hr in gmane.comp.python.general: def fun1(params_used_below_except_lk_and_lk2): lk = 0.0 lk2 = 0.0 for raw_data, hist, freq in raw_data_hist_list: lk2 = lk2 + fun2(some_constants_and_params_from_this_scope) q = fun2(same_args_as_before) lk = lk + q print lk, lk2 For some set of input parameters, This function with specific input prints out the same constant twice (as expected): 15377.7424582 15377.7424582 (twice the same value) If I comment out lines q = fun2 and lk = lk + q, fun1, with the same parameters, prints: 0.0 3.3469936856 First value is expected, but I cannot understand how come the second value is different in these two cases! Clearly the value returned by fun2 (get_beta_func_fit_quality_hist_lk) is different the second time you call it. So it either depends on and modifies a global or a value referenced or contained in one of the arguments. Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: subprocess pipe question
Rita wrote in news:AANLkTi=88dcpm_kqrs2g620obsnxz0majubfwpeme...@mail.gmail.com in gmane.comp.python.general: [Top post relocated] On Tue, Feb 22, 2011 at 7:57 PM, Rob Williscroft r...@rtw.me.uk wrote: Rita wrote in news:AANLkTi=w95gxosc1tkt2bntgjqys1cbmdnojhokq4...@mail.gmail.com in gmane.comp.python.general: When using wait() it works a bit better but not consistent def run(cmd): p=subprocess.Popen(cmd,stdout=subprocess.PIPE) rc=p.wait() print rc return p.stdout When the output of cmd is a small ascii file it works perfectly fine, but when the file is large (more than 2MB) the process just waits for ever (I am guessing its blocking?). Your OS has supplied a pipe buffer of 2MB, its full and the prossess is waiting until you read something from the pipe (i.e. p.stdout.read()). When I use the communicate call it works perfectly but my process is consuming way too much memory. Is there a better way to get my return code consistently efficiently and not take up so much memory? If you don't need the processes output then don't use the PIPE argument. If you do you will need to read from p.stdout until the process is complete, then get the return code: while True: buf = p.stdout.read( 1024 ) # do somthing with buf if len( buf ) 1024: break rc = p.wait() For extra points is there a way to speed up the p.stdout.read(bufsize) ? Its unlikely that is the problem, most likely you are reading all of the 2MB OS pipe buffer and then having to wait for the programme you are calling to produce some more output. Before trying to speed things up be sure to test with real work being done to the output you recieve. If its still slow and you have multiple cores/processors then you will need to put you read loop in a thread to speed it up. -- Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: subprocess pipe question
Rita wrote in news:AANLkTi=w95gxosc1tkt2bntgjqys1cbmdnojhokq4...@mail.gmail.com in gmane.comp.python.general: When using wait() it works a bit better but not consistent def run(cmd): p=subprocess.Popen(cmd,stdout=subprocess.PIPE) rc=p.wait() print rc return p.stdout When the output of cmd is a small ascii file it works perfectly fine, but when the file is large (more than 2MB) the process just waits for ever (I am guessing its blocking?). Your OS has supplied a pipe buffer of 2MB, its full and the prossess is waiting until you read something from the pipe (i.e. p.stdout.read()). When I use the communicate call it works perfectly but my process is consuming way too much memory. Is there a better way to get my return code consistently efficiently and not take up so much memory? If you don't need the processes output then don't use the PIPE argument. If you do you will need to read from p.stdout until the process is complete, then get the return code: while True: buf = p.stdout.read( 1024 ) # do somthing with buf if len( buf ) 1024: break rc = p.wait() Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: list 2 dict?
Octavian Rasnita wrote in news:0db6c288b2274dbba5463e7771349...@teddy in
gmane.comp.python.general:
Hi,
If I want to create a dictionary from a list, is there a better way
than the long line below?
l = [1, 2, 3, 4, 5, 6, 7, 'a', 8, 'b']
d = dict(zip([l[x] for x in range(len(l)) if x %2 == 0], [l[x] for x
in range(len(l)) if x %2 == 1]))
print(d)
{8: 'b', 1: 2, 3: 4, 5: 6, 7: 'a'}
dict( zip( l[ :: 2 ], l[ 1 :: 2 ] ) )
{8: 'b', 1: 2, 3: 4, 5: 6, 7: 'a'}
If you don't know about slice notation, the synatax I'm using above is:
list[ start : stop : step ]
where I have ommited the stop item, which defaults to the length of the
list.
http://docs.python.org/library/stdtypes.html#sequence-types-str-unicode-
list-tuple-bytearray-buffer-xrange
That will make 3 lists before it makes the dict thought, so if the
list is large:
dict( ( l[ i ], l[ i + 1 ] ) for i in xrange( 0, len( l ), 2 ) )
may be better.
Rob.
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Re: How to test if a module exists?
Jon Dufresne wrote in news:aanlktikr5euhqpupa3yrid98oas92zfhk8u9lha5y...@mail.gmail.com in gmane.comp.python.general: try: import extension_magic_module except ImportError: pass else: handle_extension_magic_module() However, if the the extension module exists but throws an ImportError, due to a bug in the extension this idiom will mask the error and I will never see it. import imp try: m = imp.find_module( test_1 ) if m[0]: m[0].close() except ImportError: pass else: import test_1 http://docs.python.org/library/imp.html#imp.find_module Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: dumping generator
targetsmart wrote in news:cd83533b-f51e-4955-96c5-f8a10185bef1 @i18g2000pro.googlegroups.com in gmane.comp.python.general: Right now if I want to dump the contents of a generator object I use , a snip from a bigger block of code.. try: while gen: print gen.next() except StopIteration: print Done else: raise is there a much simpler way ? print list( gen ) like for printing list we do list = range(10) print list would print [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Pick items from list with probability based upon property of list member ?
southof40 wrote in news:da3cc892-b6dd-4b37-a6e6- b606ef967...@t26g2000prt.googlegroups.com in gmane.comp.python.general: I have list of of N Vehicle objects - the only possible vehicles are cars, bikes, trucks. I want to select an object from the list with a probability of : cars 0.7, bikes 0.3, trucks 0.1. Aside, all your probabilities add up to 1.1, they should add up to 1. I've currently implemented this by creating another list in which each car object from the original list appears 7 times, each bike 3 times and each truck once. I then pick at random from that list. Aside, so 7 / 11 bikes, 3 / 11 cars and 1 / 11 trucks, are your actual probabilities. But to answer your question, you could create 3 list, and then pick the list you draw from based on a random number then pick the item from the list based on another random number: r = ( random() * 11 ) if r 1: picklist = truck_list elif r 4: picklist = bike_list else: picklist = car_list # now pick the final item from pick list. Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: UnicodeDecodeError having fetch web page
Kushal Kumaran wrote in news:1274889564.2339.16.ca...@nitrogen in gmane.comp.python.general: On Tue, 2010-05-25 at 20:12 +, Rob Williscroft wrote: Barry wrote in news:83dc485a-5a20-403b-99ee-c8c627bdbab3 @m21g2000vbr.googlegroups.com in gmane.comp.python.general: Hi, The code below is giving me the error: Traceback (most recent call last): File C:\Users\Administratör\Desktop\test.py, line 4, in module UnicodeDecodeError: 'utf8' codec can't decode byte 0x8b in position 1: unexpected code byte What am i doing wrong? It may not be you, en.wiktionary.org is sending gzip encoded content back, it seems to do this even if you set the Accept header as in: request.add_header( Accept, text/html ) But maybe I'm not doing it correctly. You need the Accept-Encoding: identity header. http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html Thanks, following this I did change the line to be: request.add_header( Accept-Encoding, identity ) but it made no difference to en.wiktionary.org it just sent the back a gzip encoded response. Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: UnicodeDecodeError having fetch web page
Barry wrote in news:83dc485a-5a20-403b-99ee-c8c627bdbab3
@m21g2000vbr.googlegroups.com in gmane.comp.python.general:
Hi,
The code below is giving me the error:
Traceback (most recent call last):
File C:\Users\Administratör\Desktop\test.py, line 4, in module
UnicodeDecodeError: 'utf8' codec can't decode byte 0x8b in position 1:
unexpected code byte
What am i doing wrong?
It may not be you, en.wiktionary.org is sending gzip
encoded content back, it seems to do this even if you set
the Accept header as in:
request.add_header( Accept, text/html )
But maybe I'm not doing it correctly.
#encoding: utf-8
import urllib
import urllib.request
request = urllib.request.Request
(url='http://en.wiktionary.org/wiki/baby',headers={'User-
Agent':'Mozilla/5.0 (X11; U; Linux i686) Gecko/20071127
Firefox/2.0.0.11'} )
response = urllib.request.urlopen(request)
info = response.info()
enc = info[ 'Content-Encoding' ]
print( Encoding: + enc )
from io import BytesIO
import gzip
buf = BytesIO( response.read() )
unziped = gzip.GzipFile( wahatever, mode = 'rb', fileobj = buf )
html = unziped.read().decode('utf-8')
print( html.encode( ascii, backslashreplace ) )
Rob.
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Re: py2exe help
jim-on-linux wrote in news:mailman.74.1273614703.32709.python-l...@python.org in comp.lang.python: python help, I'm open for suggestions. I'm using py2exe to compile a working program. The program runs and prints fine until I compile it with py2exe. After compiling the program, it runs fine until it tries to import the win32ui module, v2.6214.0. Then, I get a windows error message: ImportError: Dll load failed: This application has failed to start because the application configuration is incorrect. Reinstalling the application may fix this problem. Anyone have the same problem with this?. http://www.py2exe.org/index.cgi/Py2exeAndWin32ui Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Sublassing tuple works, subclassing list does not
Frank Millman wrote in news:mailman.1360.1270018159.23598.python- l...@python.org in comp.lang.python: I came up with a simple solution that seems to work - class MyTuple(tuple): ... def __new__(cls, names, values): ... for name, value in zip(names, values): ... setattr(cls, name, value) ... return tuple.__new__(cls, values) ... names = ['A', 'B', 'C'] values = ['a', 'b', 'c'] tup = MyTuple(names, values) Are you aware you are adding attributes to the class here, IOW: MyTuple.C == 'c' If you want to add attibutes to the instance: class MyTuple(tuple): def __new__(cls, names, values): r = tuple.__new__(cls, values) for name, value in zip(names, values): setattr(r, name, value) return r names = ['A', 'B', 'C'] values = ['a', 'b', 'c'] tup = MyTuple(names, values) assert tup[0] == 'a' assert tup.B == 'b' try: MyTuple.C except AttributeError: pass else: assert False -- http://mail.python.org/mailman/listinfo/python-list
Re: affectation in if statement
samb wrote in news:5c361012-1f7b-487f-915b-0f564b238be3
@e1g2000yqh.googlegroups.com in comp.lang.python:
Thanks for all those suggestions.
They are good!
1) Let's suppose now that instead of just affecting thing =
m.group(1), I need to do a piece of logic depending on which match I
entered...
2) Concerning the suggestion :
m = re.match(r'define\s+(\S+)\s*{$', line)
if m:
thing = m.group(1)
m = re.match(r'include\s+(\S+)$', line)
if m:
thing = m.group(1)
#etc...
It means that I'll do all the checks, even if the first one did match
and I know that the next will not...
Ths is how I did it when I had the need:
class ReMatch( object ):
def __call__( self, pat, string ):
import re
self.match = re.match( pat, string )
return self.match is not None
clip = ...
re = ReMatch()
if re( r'\s*TM(\d+)', clip ):
...
elif re( r'\s*(https?://.*)', clip ):
...
elif re( r'\d{12}$', clip ):
...
Rob.
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Re: Method / Functions - What are the differences?
Michael Rudolf wrote in news:hmdo3m$28...@news.urz.uni-heidelberg.de in comp.lang.python: Note that all I did was moving the list and foo into the instance. Still no self and no cls, but also no static behaviour any more. Yes in the first case foo was an attribute of the class, and in the second an attribute of aon instance of the class. In both cases it was a bound method, something similar too: lambda item : T.x.append( item ) -- http://mail.python.org/mailman/listinfo/python-list
Re: python crash on windows but not on linux
hjebbers wrote in news:2864756a-292b-4138-abfd- 3348b72b7...@u9g2000yqb.googlegroups.com in comp.lang.python: the information about the error is a windows dump. This may help: # http://msdn.microsoft.com/en-us/library/ms680621(VS.85).aspx SEM_FAILCRITICALERRORS = 1 SEM_NOALIGNMENTFAULTEXCEPT = 4 SEM_NOGPFAULTERRORBOX = 4 SEM_NOOPENFILEERRORBOX = 8 import ctypes from ctypes.wintypes import UINT SetErrorMode = ctypes.windll.kernel32.SetErrorMode SetErrorMode.restype = UINT SetErrorMode.argtypes = ( UINT,) Then putting: SetErrorMode( SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX ) at the start of you programme, should stop the Critical Error dialog box you are seeing and you may get a chance to see a traceback. Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Problem Regarding Queue
mukesh tiwari wrote in news:80fed7d5-76eb-40c8-ace1-0c35736de399 @t17g2000prg.googlegroups.com in comp.lang.python: Could some one please tell what is wrong with this code. I am trying to use Queue in this program but i am getting error The type you appear to be trying to use is Queue.Queue which you import with: from Queue import Queue http://docs.python.org/library/queue.html?highlight=queue#Queue.Queue Q_1=Queue() Q_2=Queue() Q_1.put(n) while(not Q_1.empty()): l=Q_1.get() if(rabin_miller(l)): Q_2.put(l) continue d=pollard(l) if(d==l):Q_1.put(l) else: As the help page above points out also check out the deque Class: http://docs.python.org/library/collections.html#collections.deque Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: pointless musings on performance
mk wrote in news:mailman.915.1259064240.2873.python-l...@python.org in comp.lang.python: def pythonic(): def unpythonic(): Decidedly counterintuitive: are there special optimizations for if nonevar: type of statements in cpython implementation? from dis import dis dis( unpythonic ) 18 31 LOAD_FAST0 (nonevar) 34 LOAD_CONST 0 (None) 37 COMPARE_OP 9 (is not) 40 JUMP_IF_FALSE4 (to 47) dis( pythonic ) 11 31 LOAD_FAST0 (nonevar) 34 JUMP_IF_FALSE4 (to 41) Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: pointless musings on performance
mk wrote in news:mailman.923.1259070092.2873.python-l...@python.org in comp.lang.python: MRAB wrote: In what way is it counterintuitive? In 'pythonic' the conditions are simpler, less work is being done, therefore it's faster. But the pythonic condition is more general: nonevar or zerovar can be '', 0, or None. So I thought it was more work for interpreter to compare those, while I thought that is not None is translated to one, more low-level and faster action. Apparently not. As Rob pointed out (thanks): 11 31 LOAD_FAST0 (nonevar) 34 JUMP_IF_FALSE4 (to 41) I'm no good at py compiler or implementation internals and so I have no idea what bytecode JUMP_IF_FALSE is actually doing. IIUC it implements: http://docs.python.org/3.1/reference/expressions.html#boolean-operations In the context of Boolean operations, and also when expressions are used by control flow statements, the following values are interpreted as false: False, None, numeric zero of all types, and empty strings and containers (including strings, tuples, lists, dictionaries, sets and frozensets). All other values are interpreted as true. User-defined objects can customize their truth value by providing a __bool__() method. In particular its implementing ... Boolean operation ... used by control flow ..., all in one handy op code. Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Help with database planning
Juliano wrote in news:0e64893a-af82-4004-bf3c-f397f2022...@g22g2000prf.googlegroups.com in comp.lang.python: [snip] So, for ONE *concept*, we have, usually, MANY *slots*, each *slot* has ONE *facet*, and each *facet* can have MORE THAN ONE *filler*. Besides, some *slots* and *fillers* are themselves *concepts*, creating a sort of recursive reference. What I'm grokking from the data you show is that a Concept is a table (or a python class), slots are attributes of the concept and facets are the type of slot, finally the fillers are (mostly) the data. But also you seem to have slots that represent relationships between Concepts and other tables, in this case the slots should be tables. For example with the slot type INSTANCE-OF, what is OTHER-NIGER-KORDOFANIAN-LANGUAGE is it another concept or a list of concepts or a concept OTHER-NIGER-KORDOFANIAN and a type LANGUAGE, I suspect you have a table Language and also an table Region in there too. It may be time to start thinking in terms of what you are modeling and what the entities are (as apposed to trying to convert the data you have), once you have that, work out how to load that data from your current file and check that you can query your model correctly. Maybe something like (using a made up ORM): class Concept: name = TextField() definition = TextField() primary_key = PrimaryKey( name ) class IsASlot: concept = ForeignKey( Concept ) is_a = ForeignKey( Concept ) primary_key = PrimaryKey( concept, is_a ) class LexeSlot: concept = ForeignKey( Concept ) value = TextField() primary_key = PrimaryKey( concept, value ) class Region: region = TextField() primary_key = PrimaryKey( region ) class Language: language = ForeignKey( Concept ) # or is it TextField() ? primary_key = PrimaryKey( language ) class LanguageOfSlot: language = ForeignKey( Language ) region = ForeignKey( Region ) primary_key = PrimaryKey( language, region ) To reiterate, you should use your domain expertise to create the model. begin table line_no concepts slots facets fillers --- --- 0 ABANDON DEFINITION VALUE to leave or desert something or someone 1 ABANDON IS-A VALUE EXIT 2 ABANDON LEXE MAP-LEX leave behind-V1 3 ABANDON LEXE MAP-LEX abandon-V1 The -V1 in the above looks worryingly like you have structure embedded in the data field, if so you should extract is so its in its own field or table. (...) 97420 ZULU DEFINITION VALUE a language or dialect spoken in south africa and others 97421 ZULU INSTANCE-OF VALUE OTHER-NIGER-KORDOFANIAN-LANGUAGE 97422 ZULU LANGUAGE-OF INV LESOTHO 97423 ZULU LANGUAGE-OF INV SOUTH-AFRICA Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: creating class objects inside methods
Benjamin Kaplan wrote in news:mailman.838.1254682604.2807.python- l...@python.org in comp.lang.python: And how do you just check a script's syntax without running it anyways? ) Because these aren't compile-time errors. Python has no compilation phase- Sure it does, compilation happens for every script that is executed. And for every import, if the pre-compiled byte code can't be found it is compiled (and the byte code saved as a .pyc or .pyo file). Its only when a the interpreter has the complete compiled byte code for a script or imported module that it executes anything. Python could, if it was wanted, detect multiple syntax and other compilation errors, but AIUI the (CPython) developers choose not to, as it significantly simplifies (and thus speeds up) the compilation process, which can be significant for an interpreted language. For example I just ran a script with the one line: print hello world through IronPython (2.0 (2.0.0.0) on .NET 2.0.50727.3082) I counted 1 and 2 and ... 12 before I seeing hello world (Aside I think this is something that the current IronPython beta (2.6) fixes, but I havent tried it myself yet.) every statement (including def and class) is an executable Yes but for example the execution of the statement: def example() : pass just assignes (binds) the compiled function to the name example. statement and it gets turned into byte code at execution time. Just like any other language, when Python hits a runtime error, it stops. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: socket send O(N**2) complexity
Zac Burns wrote in news:mailman.211.1253559803.2807.python-l...@python.org in comp.lang.python: The mysocket.mysend method given at http://docs.python.org/howto/sockets.html has an (unwitting?) O(N**2) complexity for long msg due to the string slicing. I've been looking for a way to optimize this, but aside from a pure python 'string slice view' that looks at the original string I can't think of anything. Perhaps start and end keywords could be added to send? I can't think of a reason for the end keyword, but it would be there for symmetry. I ran this script on various versions of python I have access to: #encoding: utf-8 raw_input( start ) s = 'x' * 100 r = [None] * 1000 raw_input( allocated 1 meg + ) for i in xrange(1000): r[i] = s[:] raw_input( end ) Niether of the CPython versions (2.5 and 3.0 (with modified code)) exibited any memory increase between allocated 1 meg + and end pypy-c (1.0.0) showed a 30k jump, and IronPython 2.0 showed a few megs jump. AIUI, as a python string is imutable, a slice of a string is a new string which points (C char *) to the start of the slice data and with a length that is the length of the slice, about 8 bytes on 32 bit machine. So even though a slice assignment new_s = s[:] appears to a python programmer to make a copy of s, its only the a few bytes of metadata (the pointer and the length) that is really copied, the strings character data stays where it is. So the code you cite is in fact O(N) as the copy is constant size. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: socket send O(N**2) complexity
wrote in news:mailman.216.1253565002.2807.python-l...@python.org in comp.lang.python: Niether of the CPython versions (2.5 and 3.0 (with modified code)) exibited any memory increase between allocated 1 meg + and end You bumped into a special case that CPython optimizes. s[:] is s. If you repeat your test with s[1:], you'll see memory climb as one might normally expect. Thanks for the correction (to Jack also) Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: what is the biggest number that i can send to Wave_write.writeframes(data)
'2+ wrote in news:mailman.1017.1243932401.8015.python-l...@python.org in
comp.lang.python:
would like to take advantage of the wave module
found a good example here:
http://www.python-forum.org/pythonforum/viewtopic.php?f=2t=10644
hmm .. i don't get how to write a stereo .. i mean i can set nchannels
.. but how do i actually take control of each ch individually?
Interleave the channels, one sample for the left then one sample
for the right (or maybe its the other way around).
and what's the range(in float) of the data i can set in
The range of a signed 16 bit int, -2**15 to 2**15 - 1.
wav_file.writeframes(struct.pack('h', data))?
Example:
import wave
from StringIO import StringIO
out = StringIO()
AMPLITUDE = 2 ** 15
w = wave.open( out, w )
w.setnchannels( 2 )
w.setsampwidth( 2 ) #BYTES
w.setframerate( 22000 )
from array import array
import math
F = 261.626
F2 = F * (2 ** (5 / 12.))
ang = 0.0
ang2 = 0.0
delta = ( math.pi * 2 * F ) / 22000.0
delta2 = ( math.pi * 2 * F2 ) / 22000.0
for cycle in xrange( 4 ):
data = array( 'h' )
for pos in xrange( 22000 ):
amp = AMPLITUDE * (pos / 22000.0)
amp2 = AMPLITUDE - amp
if cycle 1:
amp, amp2 = amp2, amp
data.append( int( ( amp * math.sin( ang ) ) ) )
data.append( int( ( amp2 * math.sin( ang2 ) ) ) )
ang += delta
ang2 += delta2
w.writeframes( data.tostring() )
w.close()
sample = out.getvalue()
out.close()
#a wx player
import wx
app = wx.PySimpleApp()
class Frame( wx.Dialog ):
def __init__( self, *args ):
wx.Dialog.__init__( self, *args )
b = wx.Button( self, -1, Ok )
b.Bind( wx.EVT_BUTTON, self.button )
def button( self, event ):
self.sound = wx.SoundFromData( sample )
self.sound.Play( wx.SOUND_ASYNC )
frame = Frame( None )
frame.Show()
app.MainLoop()
Rob.
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Re: Questions about regex
wrote in news:fe9f707f-aaf3-4ca6-859a-5b0c63904fc0
@s28g2000vbp.googlegroups.com in comp.lang.python:
text = re.sub('(\(/?[^\]+)\)', , text)#remove the HTML
Python has a /r/ (raw) string literal type for regex's:
text = re.sub( r'(\(/?[^\]+)\)', , text )
In raw strings python doesn't process backslash escape sequences
so r\n' is the 2 char' string '\\n' (a backslash folowed by an 'n').
Without that your pattern string would need to be writen as:
'(\\(/?[^\\]+)\\)'
IOW backslashes need to be doubled up or python will process them
before they are passed to re.sub.
Also this seems to be some non-python dialect of regular expression
language, Pythons re's don't need to escape and .
http://docs.python.org/library/re.html
The grouping operators, '(' and ')', appear to be unnessasery,
so altogether this 1 line should probably be:
text = re.sub( r'/?[^]+', '', text )
Rob.
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Re: sqlite single transaction without foreign key or triggers
John Machin wrote in news:b722bd36-c8f1-4cdf-8625-2550cee21511 @i28g2000prd.googlegroups.com in comp.lang.python: On May 13, 11:46 am, a...@pythoncraft.com (Aahz) wrote: In article xns9c09513903e8frtwfreenetremovec...@216.196.109.145, Rob Williscroft r...@freenet.co.uk wrote: Aahz wrote innews:guao50$1j...@panix3.panix.comin comp.lang.python: In article xns9c08e179b66d8rtwfreenetremovec...@216.196.109.145, Rob Williscroft r...@freenet.co.uk wrote: db.execute( ''' update sessions set uid = ? where uid = ? and exists( select * from users where uid = ? ) ''', (v['uid'],s.SID, v['uid']) ) This will be more efficient if you do select uid from users. What will be more efficient ? Do you mean the select * ... or do you want to take the exists sub-query out and put it in a python if ? select uid will be more efficient than select *, although I suppose I could be wrong about that given how little I know about current query optimizers. It seems the usual advice about premeture optimisation should apply, namely write clear code (*), then optimise the bottlenecks when you actualy find you need to. *) for some definition of clear code. My take is that it won't matter what you select if the optimiser is smart enough; something that requires minimal resources to produce is indicated in case the optimiser is dumb: ... exists (select 1 from ... ) I have to maintain some code writen by someone who thinks replacing * in queries with 1 is always a good idea (you know just in case), he wrote: select count(1) from ... of course it didn't do what he thought it did. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: sqlite single transaction without foreign key or triggers
Aahz wrote in news:guao50$1j...@panix3.panix.com in comp.lang.python: In article xns9c08e179b66d8rtwfreenetremovec...@216.196.109.145, Rob Williscroft r...@freenet.co.uk wrote: db.execute( ''' update sessions set uid = ? where uid = ? and exists( select * from users where uid = ? ) ''', (v['uid'],s.SID, v['uid']) ) This will be more efficient if you do select uid from users. What will be more efficient ? Do you mean the select * ... or do you want to take the exists sub-query out and put it in a python if ? Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: sqlite single transaction without foreign key or triggers
gert wrote in news:d7591495-4661-4243-ad7e-f142d8244e88
@e24g2000vbe.googlegroups.com in comp.lang.python:
I am trying to do this in a single transaction, the 3 separate
statements work fine, but i am screwed if they are not executed
together.
Well you're in luck, Python DBAPI 2 connections handle this
for you, you do need to call commit() on the connection though.
The default, for DBAPI 2 connections, is that all work occurs in a
transaction (if the DB actually supports transactions) so you have to
call commit() on the connection after doing updates.
### db.execute('BEGIN') #
db.execute('UPDATE users SET uid=? WHERE uid=?',(v['uid'],s.UID))
This is a fragile way to do it, your code won't work with a DB that
has real foreign keys (and maybe sqlite will get them one day).
A less fragile way of doing it is:
db = connection.cursor()
# First copy the row if it exists
db.execute( '''
insert into users
select ?, name, adress, city, country, phone, picture
from users where uid = ?
''', (v['uid'],s.UID)
)
db.execute('UPDATE sessions SET uid=? WHERE sid=?',(v['uid'],s.SID))
# Second update foriegn key tables to point to the new row
# (but only if the new row exists )
db.execute( '''
update sessions set uid = ?
where uid = ?
and exists(
select * from users where uid = ?
)
''',
(v['uid'],s.SID, v['uid'])
)
#Do the same for the groups table, then
# finally delete the original row (again only if the new row exists )
db.execute( '''
delete from users
where uid = ?
and exists(
select * from users where uid = ?
)
''',
(s.SID, v['uid'])
)
# Finally commit the transaction
connection.commit()
# only do this if there is no primary key conflict in the above
if db.ERROR == None: db.execute('UPDATE groups SET uid=? WHERE uid=?',
(v['uid'],s.UID))
Python reports errors by throwing exceptions, so if you needed somthing
like this it would more likely be:
try:
... # somthing that errors up ...
catch sqlite3.DatabaseError:
connection.rollback()
Rob.
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Re: pyAA for Python2.5
Kottiyath wrote in news:d86a0c1d-e158-4aa1-a47f-e2149948bdc3 @p2g2000prf.googlegroups.com in comp.lang.python: On Jan 29, 1:51 am, Rob Williscroft r...@freenet.co.uk wrote: Kottiyath wrote in news:6a594643-f6a2-4d8d-aab3-27eb16cb2fb8 @b38g2000prf.googlegroups.com in comp.lang.python: I have mingw32-gcc in my path. If I try that too -it fails. C:\Documents and Settings\Guest\pyAApython setup.py install -c mingw32-gcc invalid command name 'mingw32-gcc' All the examples I found via google have the tool name as mingw32 so try: python setup.py install -c mingw32 Thank you Rob. The installation went ahead for some more time - but failed showing a lot of errors: compile running build running build_py file pyAAc.py (for module pyAAc) not found file pyAAc.py (for module pyAAc) not found ... pyAAc.cpp:5887: error: `EVENT_OBJECT_HELPCHANGE' was not declared in this scope pyAAc.cpp:5888: error: `EVENT_OBJECT_DEFACTIONCHANGE' was not declared in this scope pyAAc.cpp:5889: error: `EVENT_OBJECT_ACCELERATORCHANGE' was not declared in this scope ... error: command 'gcc' failed with exit status 1 I cannot understand why it fails. I have not worked in C till now, so I am pretty confused. I googled also, but to no avail. Looks like the package needs some headers that haven't yet been ported to to MinGW. Alas that meands you'll need to build with the Microsoft SDK and compiler. You can get the SDK including a non-optimising compiler from: http://www.microsoft.com/downloads/details.aspx?FamilyId=9B3A2CA6-3647- 4070-9F41-A333C6B9181Ddisplaylang=en or maybe here: http://www.microsoft.com/downloads/details.aspx?FamilyId=0BAF2B35-C656- 4969-ACE8-E4C0C0716ADBdisplaylang=en Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: pyAA for Python2.5
Kottiyath wrote in news:6a594643-f6a2-4d8d-aab3-27eb16cb2fb8 @b38g2000prf.googlegroups.com in comp.lang.python: I have mingw32-gcc in my path. If I try that too -it fails. C:\Documents and Settings\Guest\pyAApython setup.py install -c mingw32-gcc invalid command name 'mingw32-gcc' All the examples I found via google have the tool name as mingw32 so try: python setup.py install -c mingw32 or python setup.py build --compiler=mingw32 install The compiler that the MinGW package installs is gcc. You shoulf be able to verify it is on your path by typing: gcc --help or gcc --version and see some output. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Start Python at client side from web app
Thomas Guettler wrote in news:6tr453fca5h...@mid.individual.net in comp.lang.python: Diez B. Roggisch schrieb: 2) create a localhost web server, for the client side manipulation. Then have your remote webserver render a form that posts via javavscript to the localhost webserver. The localhost server would post back in the same way. AFAIK the JS security model prevents that. A page requested from http://myintranetserver/; can redirect to http://localhost:myport/myapp/?foo=...; this would work. But how should the web server at localhost be started? You need to write a Windows service. Since there will be only one client a regular programme should be fine. I guess that's not very easy, since I am not used to windows programming. Then don't do any (windows programming), do Python: http://docs.python.org/3.0/library/wsgiref.html#module- wsgiref.simple_server http://docs.python.org/3.0/library/cgi.html#functions Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Start Python at client side from web app
Diez B. Roggisch wrote in news:6ts0dnfc9s0...@mid.uni-berlin.de in comp.lang.python: Rob Williscroft schrieb: Diez B. Roggisch wrote in news:6tpo16fbacf...@mid.uni-berlin.de in comp.lang.python: 2) create a localhost web server, for the client side manipulation. Then have your remote webserver render a form that posts via javavscript to the localhost webserver. The localhost server would post back in the same way. AFAIK the JS security model prevents that. Are you thinking of frames?, or the way IE 7 complains about runnning javavscript (though it bizzarly calls it an running an ActiveX control )?. Before posting, I tried a jQuery-ajax-call inside Firebug from some random site to google. It bailed out with a security execption. Yes the XMLHttpRequest object only allows you to make requests to the same domain as the page came from. Here is a concrete example of what I suggested: body onload=document.forms[0].submit(); form action=http://localhost:8000/...; input ... /form /body I.e. 1 line of JS that is manipulating the document of the page it belongs to. And I found this: The Same-Origin Policy The primary JavaScript security policy is the same-origin policy. The same-origin policy prevents scripts loaded from one Web site from getting or setting properties of a document loaded from a different site. This policy prevents hostile code from one site from taking over or manipulating documents from another. Without it, JavaScript from a hostile site could do any number of undesirable things such as snoop keypresses while youâre logging in to a site in a different window, wait for you to go to your online banking site and insert spurious transactions, steal login cookies from other domains, and so on. http://www.windowsitlibrary.com/Content/1160/22/1.html Now there might be ways around this - but these sure are hacky, and not exactly the thing to look after. That is scripting across frames (or windows), where the frames have a different origin (from different domain). As an aside if the OP's app' can live with sending at most about 1KB of ascii back and forth then using a HTTP redirect header is another option. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: list subsetting
culpritNr1 wrote in news:mailman.7713.1232574803.3487.python-l...@python.org in comp.lang.python: Hello All, Say I have a list like this: a = [0 , 1, 3.14, 20, 8, 8, 3.14] Is there a simple python way to count the number of 3.14's in the list in one statement? In R I do like this a = c(0 , 1, 3.14, 20, 8, 8, 3.14) length( a[ a[]==3.14 ] ) How do I do that in standard python? count = a.count( 3.14 ) (Note that this is just an example, I do not mean to use == in floating point operations.) In this case something like this: a = [0 , 1, 3.14, 20, 8, 8, 3.14] count = sum( 1 for x in a if 3.13 x and x 3.15 ) http://docs.python.org/library/functions.html#sum http://docs.python.org/reference/expressions.html#generator-expressions Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Start Python at client side from web app
Thomas Guettler wrote in news:6toehtfbrb8...@mid.individual.net in comp.lang.python: Sorry, I described my problem not well. Here is more information: The main application is the intranet web application used with IE (ms windows client). But some action needs to be done on the client since you can't do it with html or javascript. 1. The user pushes a button in the web app. 2. Webserver sends signed python code to the client with own mime type 3. IE sends code to the python application. 4. Signature gets checked, Python code on the client gets executed. 5. Maybe send some data to the server with http. Thomas Server runs Linux with Django and Postgres. Thomas Guettler schrieb: Hi, I want to start Python at the client side from a web application. The app is an intranet application, and all client PCs are under our control (we can install software on them). But I don't want to update the installation too often. Here is my idea: We create a custom mime-type and register it on the client PC. The web application can send signed python code to the client PC. If the signature is correct, the code will be executed at the client. The signature prevents others from executing code. Has someone seen or done something like this before? Two options come to mind: 1) use a HTA as you client app, http://msdn.microsoft.com/en-us/library/ms536496(VS.85).aspx The main drawback is it isn't a full browser so you loose things like back buttons, though some shortcuts F5 (refresh/reload) do work. 2) create a localhost web server, for the client side manipulation. Then have your remote webserver render a form that posts via javavscript to the localhost webserver. The localhost server would post back in the same way. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Start Python at client side from web app
Diez B. Roggisch wrote in news:6tpo16fbacf...@mid.uni-berlin.de in comp.lang.python: 2) create a localhost web server, for the client side manipulation. Then have your remote webserver render a form that posts via javavscript to the localhost webserver. The localhost server would post back in the same way. AFAIK the JS security model prevents that. Are you thinking of frames?, or the way IE 7 complains about runnning javavscript (though it bizzarly calls it an running an ActiveX control )?. Anyway it works fine. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 3: exec arg 1
Alan G Isaac wrote in news:myhdl.805$aw2@nwrddc02.gnilink.net in comp.lang.python: On 1/18/2009 9:36 AM Alan G Isaac apparently wrote: I do not much care about the disappearance of ``execfile``. I was asking, why is it a **good thing** that ``exec`` does not accept a TextIOWrapper? Or is it just not implemented yet? What is the gain from this particular backwards incompatibility (in the sense that ``exec(open(fname))`` no longer works)? Still interested in an answer... Alan Isaac http://bugs.python.org/issue1762972 (*) IIRC, exec(open(fname).read()) is the Py 3.0 replacement. *) For reference, 2 clicks away from url:http://www.google.co.uk/search? hl=enq=TextIOWrapper+exec+site%3Abugs.python.orgmeta= Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: function argument dependent on another function argument?
Aaron Brady wrote in news:6a10378f-addb-4d56-bc1b-0c382b3cb...@t26g2000prh.googlegroups.com in comp.lang.python: On Jan 18, 9:36 am, Paul Rubin http://phr...@nospam.invalid wrote: Steven D'Aprano st...@remove-this-cybersource.com.au writes: def foo(self, x, y=None): if y is None: y = self.a I don't find that clumsy in the least. I find it perfectly readable and a standard idiom. That has the same problem as the earlier version. If the person passes None, they get self.a. I prefer: sentinel = object() ... def foo(x, y=sentinel): if y is sentinel: y = self.a It is too bad that it is so much work to detect whether 'y' was passed in the function call directly. However, sentinel is just as good (or nearly); at worst, you need one sentinel per argument per function, One per Module should be good enough. The only reason None doesen't suffice is that it has other legitimate uses. Though to be honest I would always use None as the sentinel if it wasn't a legitimate argument. which is possible to create, which has a specific meaning. If you are making systematic function calls, e.g. with a dictionary or list, you can just use the sentinel in the dictionary. IIUYC then, one sentinel is still only needed as the missing argument is indicated by *both* position and value or by name and value (in the case of a keyword-dictionary), so seperate distinct sentinel objects aren't required, for example: SENTINEL = object() def f( a, b, c = SENTINEL, d = SENTINEL ): print( values: %r % ( ( a, b, c, d ), ) ) if c is SENTINEL: print( c is missing ) if d is SENTINEL: print( d is missing ) f( *( 1, 2, SENTINEL, SENTINEL ) ) f( **dict( a = 1 , b = 2, d = 4 ) ) f( **dict( a = 1 , b = 2, d = 4, c = SENTINEL ) ) Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 3: exec arg 1
Steven D'Aprano wrote in news:018342f9$0$8693$c3e8...@news.astraweb.com
in comp.lang.python:
I'm not sure if this is a stupid question or not, but what's a
TextIOWrapper? In the example you give:
exec(open(fname))
the argument to exec -- open(fname) -- is a file object:
type(open('hello.py'))
type 'file'
BTW, exec is a statement. The brackets there are totally superfluous.
You can, and should, write:
exec open(fname)
You must have missed the subject line: Re: Python 3: exec arg 1
Python 3.0 (r30:67507, Dec 3 2008, 19:44:23) [MSC v.1500 64 bit (AMD64)]
on win32
Type help, copyright, credits or license for more information.
open( hello.py )
io.TextIOWrapper object at 0x0212F7F0
exec a = 1
File stdin, line 1
exec a = 1
^
SyntaxError: invalid syntax
exec( a = 1 )
a
1
Rob.
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Re: function argument dependent on another function argument?
Aaron Brady wrote in
news:582ef883-0176-4984-9521-6c1894636...@a26g2000prf.googlegroups.com
in comp.lang.python:
On Jan 18, 10:44 am, Rob Williscroft r...@freenet.co.uk wrote:
Aaron Brady wrote
innews:6a10378f-addb-4d56-bc1b-0c382b3cb...@t26g2000prh
.googlegroups.com
in comp.lang.python:
It is too bad that it is so much work to detect whether 'y' was
passed in the function call directly. However, sentinel is just as
good (or nearly); at worst, you need one sentinel per argument per
function,
One per Module should be good enough. The only reason None doesen't
suffice is that it has other legitimate uses. Though to be honest
I would always use None as the sentinel if it wasn't a legitimate
argument.
which is possible to create, which has a specific meaning. If you
are
making systematic function calls, e.g. with a dictionary or list,
you can just use the sentinel in the dictionary.
IIUYC then, one sentinel is still only needed as the missing argument
is indicated by *both* position and value or by name and value (in
the case of a keyword-dictionary), so seperate distinct sentinel
objects aren't required, for example:
SENTINEL = object()
def f( a, b, c = SENTINEL, d = SENTINEL ):
print( values: %r % ( ( a, b, c, d ), ) )
if c is SENTINEL:
print( c is missing )
if d is SENTINEL:
print( d is missing )
f( *( 1, 2, SENTINEL, SENTINEL ) )
f( **dict( a = 1 , b = 2, d = 4 ) )
f( **dict( a = 1 , b = 2, d = 4, c = SENTINEL ) )
I don't have a concrete example, so you may prove to be right, but I'm
not convinced.
I'm afraid I can't think of a use case for passing default values around
eiither, and I suspect if we were to come up with one, a better solution
that didn't involve passing default values around could be found.
If you have one function with an argument that defaults to an empty
list, and calls another with an argument that defaults to an empty
dict, then what is the meaning of passing sentinel to the first one?
Whereas, if each had their own, then passing the first one's default
would mean the empty list, and passing the second one's default would
mean the dict.
If you *mean* to pass an empty list or empty dict's you should do
it like:
function_taking_list( [] )
function_taking_dict( {} )
Its when you don't (have reason to) care that you need default arguments.
(Or, even if that evaluates correctly, perhaps there is no such useful
program.)
I agree, though I think some confusion arises here as there are two
(at least) distinct meanings for default arguments in python:
1) provide a value for when the caller doesn't, eg:
def f( a = 1 ): ...
2) provide a cache for the functions /private/ use, eg:
def f( cache = {} ): ...
If the two are mixed up, then I can imagine a situation where somebody
might want to start passing default caches around. It could only end
in tears.
Rob.
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Re: Mocking `from foo import *` functions
wrote in news:a9ed10ff-d907-46f0-8c6a- c3d95579a...@k1g2000prb.googlegroups.com in comp.lang.python: To answer to Rob: yeah, sure that would work, but I always thought Just to note: you're answering a question about testing, but I answered how to alter the alerter module *for* testing. given it was the import * that was causing the OP the problem, I tried to address that. mocking the imported function didn't feel right. The test then depends on the import method of the tested module. If you later change your mind and decide to use import sender and then sender.sendEmails(), you have to change your test code. You have to add: import sender sender.sendEmails = mock_sendEmails to your test script. Note that doing the above *before* any other module imports from sender, will be sufficient in *any* case, though it won't help if the tested code calls reload( sender ). No need to scan every imported module for the mocked function. It also handles the case where other code imports the sender module and calls sendEmails(). For additional robustness the above can be changed to: ## assert sender module hasn't been imported elsewhere yet import sys assert 'sender' not in sys.modules import sender sender.sendEmails = mock_sendEmails Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Mocking `from foo import *` functions
Silfheed wrote in news:c73b304b-f601-4bb5-89c1-3ee667eeb7d9 @l37g2000vba.googlegroups.com in comp.lang.python: So I'm in the current testing situation: sender.py: - def sendEmails(): return I send emails alerter.py: - from sender import * def DoStuffAndSendEmails(): doStuff() sendEmails() I'm trying to write a test fn that will test DoStuffAndSendEmails() (as well as it's kin) without actually sending any emails out. I could go through alter alerter so that it does `import sender` and then find and replace fn() with sender.fn() so I can just create a mock fn fakeSendEmails() and and do something like sender.sendEmails = fakeSendEmails, but I'd rather not. Anyone know how to test alerter.py with out altering the file? Yes you alter the module *after* you have imported it. In your test script do: def mock_sendEmails(): pass # or some test code maybe # setup ... import alerter # now patch the module alerter.sendEmails = mock_sendEmails # run the test ... DoStuffAndSendEmails() Because python is dynamic alerter.DoStuffAndSendEmails will call the sendEmails in the alerter module that has been replaced with mock_sendEmails from the test script. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Generator metadata/attributes
wrote in news:053df793-9e8e-4855-aba1-f92482cd8922
@v31g2000vbb.googlegroups.com in comp.lang.python:
class TaggedWrapper():
def __init__(self, generator, logMixin, stream):
self.__generator = generator
self.__tag = '%...@%s' % (logMixin.describe(), stream)
logMixin._debug('Created %s' % self)
Note that self in the above is the instance of the wrapper class
TaggedWrapper, not the class that is having its (generator) method
decorated.
import logging
logging.basicConfig( level = logging.DEBUG )
def mydecorator( f ):
def decorated(self, *args):
logging.debug( Created %s, self.__class__.__name__ )
for i in f(self, *args):
yield i
return decorated
class Example( object ):
@mydecorator
def foo(self, a, b, ):
yield 1 + a + b
e = Example()
for i in e.foo( 2, 3 ):
print( i )
Output of the above is:
DEBUG:root:Created Example
6
Rob.
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Re: Generator metadata/attributes
wrote in news:d301c93a-8a73-4cbb-9601-fe0c18a94f97 @v5g2000prm.googlegroups.com in comp.lang.python: I realise I could create my own wrapper that implements __next__ (I am using Python 3 and haven't checked the exact interface required, but I guess it's something like that), and add the information that way, but I am worried I am doing something too complicated. Is there really no way to stick some arbitrary data onto a generator (from a function that yields)? In case it's any help, the decorator is basically: def mydecorator(f): def decorate(self, *args): generator = f(self, *args) You can use something like this: def mydecorator( f ): def decorated(self, *args): for i in f(self, *args): yield i decorated.__doc__ = 'madeup doc string' return decorated class Example( object ): @mydecorator def foo(self, a, b, ): yield 1 print( help( Example ) ) But realise that when the decorator (mydecorator above) is run neither the class (Example) or the instance (self) is available. Which limits somewhat the debugging information you can attach automatically. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 3.0 nonlocal statement
Matimus wrote in news:2a3d6700-85f0-4861-84c9-9f269791f044 @f40g2000pri.googlegroups.com in comp.lang.python: On Jan 6, 5:31 am, Casey casey...@gmail.com wrote: In PEP 3104 the nonlocal statement was proposed and accepted for implementation in Python 3.0 for access to names in outer scopes. The proposed syntax included an optional assignment or augmented assignment to the outer name, such as: nonlocal x += 1 This syntax doesn't appear to be supported in the 3.0 implementation. My question is: was this intentional or was it missed in the initial release? If it was intentional, is there any plan to support it in a later 3.x release? I realize it is a very small convenience feature but I have already come across a couple of cases where I use nested functions where it does make the code seem a little cleaner. Regards, Casey `nonlocal` should behave just like `global` does. It doesn't support that syntax either. So, yes it was intentional. No, there probably is no plan to support it in a later release. Matt http://www.python.org/dev/peps/pep-3104/ quote A shorthand form is also permitted, in which nonlocal is prepended to an assignment or augmented assignment: nonlocal x = 3 The above has exactly the same meaning as nonlocal x; x = 3. (Guido supports a similar form of the global statement [24].) /quote Searching (AKA googling) for: nonlocal site:bugs.python.org leads to: http://bugs.python.org/issue4199 Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: About PyOpenGL
trueli...@gmail.com wrote in news:f8099226-a953-4598-bfe2-61ee5772ce26 @l33g2000pri.googlegroups.com in comp.lang.python: Traceback (most recent call last): File test.py, line 36, in module main() File test.py, line 26, in main glutInit(sys.argv) File c:\python25\lib\site-packages\PyOpenGL-3.0.0b8-py2.5-win32.egg \OpenGL\GLUT\special.py, line 316, in glutInit _base_glutInit( ctypes.byref(count), holder ) File c:\python25\lib\site-packages\PyOpenGL-3.0.0b8-py2.5-win32.egg \OpenGL\GLUT\special.py, line 57, in _base_glutInit return __glutInitWithExit(pargc, argv, _exitfunc) File c:\python25\lib\site-packages\PyOpenGL-3.0.0b8-py2.5-win32.egg \OpenGL\platform\baseplatform.py, line 280, in __call__ self.__name__, self.__name__, OpenGL.error.NullFunctionError: Attempt to call an undefined function __glutInitWithExit, check for bool(__glutInitWithExit) before calling To get you code running I needed (in addition to the PyOpenGL download) to download. glut-3.7.6-bin.zip (117 KB) from http://www.xmission.com/~nate/glut.html and put the glut32.dll where python can find it, the readme says windows\system which worked, but sticking it in the same directory as python.exe (c:\python25 in your case) worked too. http://pyopengl.sourceforge.net/ http://pyopengl.sourceforge.net/documentation/installation.html Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Triple quoted string in exec function ?
Stef Mientki wrote in news:mailman.6399.1230668197.3487.python- l...@python.org in comp.lang.python: And, by the way, exec is a *statement*, not a function! exec ( Init_Code, PG.P_Globals ) I've really doubt that this is a statement, unless I don't understand what a statement is. In python 2.x the above is a statement that is passed a tuple: http://docs.python.org/reference/simple_stmts.html#exec its a statement like print is: print ( 1,2 ) (1, 2) In 3.x it is a function: http://docs.python.org/3.0/library/functions.html#exec print is also a function in python 3.x, so: print(1, 2) 1 2 Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Triple quoted string in exec function ?
Steven D'Aprano wrote in news:016abfa1$0$6988$c3e8...@news.astraweb.com in
comp.lang.python:
On Tue, 30 Dec 2008 15:35:28 -0600, Rob Williscroft wrote:
Stef Mientki wrote in news:mailman.6399.1230668197.3487.python-
l...@python.org in comp.lang.python:
And, by the way, exec is a *statement*, not a function!
exec ( Init_Code, PG.P_Globals )
I've really doubt that this is a statement, unless I don't understand
what a statement is.
In python 2.x the above is a statement that is passed a tuple:
http://docs.python.org/reference/simple_stmts.html#exec
The documentation doesn't say anything about it accepting a tuple as an
argument. The tuple argument works in both 2.5 and 2.6. Curious.
My mistake, it is also behaving as a function:
http://docs.python.org/dev/3.0/whatsnew/3.0.html#removed-syntax
Removed keyword: exec() is no longer a keyword; it remains
as a function. (Fortunately the function syntax was also accepted
in 2.x.) Also ...
Though that was the only documentation of it I found in a brief
web search.
I was also surprised by this behaviour:
g, l = {}, {} # no globals, no locals
exec x = 1 in g, l
l
{'x': 1}
g.keys()
['__builtins__']
I see *now* that this is documented:
...the current implementation MAY add a reference to the dictionary of
the built-in module __builtin__ under the key __builtins__ (!).
[emphasis added]
but it's still rather disconcerting. That means that:
exec some potentially dangerous code in {}, {}
isn't as safe as I thought it was.
AIUI it isn't meant to be safe, it provides some data hiding
that is useful for programming purposes but isn't much use
for security.
Another example of a security hole:
def f():
... print f()
...
exec from __main__ import f; f()
f()
Rob.
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Re: How can I return a non-zero status result from a python script?
silverburgh.me...@gmail.com wrote in news:74b53da4-bf07-431b-898b- 49977f7a6...@r36g2000prf.googlegroups.com in comp.lang.python: Hi How can I return a non-zero status result from the script? Just do a return 1? at the end? import sys help( sys.exit ) Help on built-in function exit in module sys: exit(...) exit([status]) Exit the interpreter by raising SystemExit(status). If the status is omitted or None, it defaults to zero (i.e., success). If the status is numeric, it will be used as the system exit status. If it is another kind of object, it will be printed and the system exit status will be one (i.e., failure). Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: 'new' module deprecation in python2.6
David Pratt wrote in news:mailman.4664.1227980181.3487.python-
[EMAIL PROTECTED] in comp.lang.python:
import new
class FirstBase(object):
foo = 'bar'
biz = 'baz'
class SecondBase(object):
bla = 'blu'
buz = 'brr'
attr = {
'fiz': 'An attribute', 'fuz': 'Another one'}
Test = new.classobj(
'Test', (FirstBase, SecondBase), attr)
Test = type(
'Test', (FirstBase, SecondBase), attr)
class MyNewClass(Test):
pass
a = MyNewClass()
print a.foo, a.buz, a.fiz, type(a)
print( ( a.foo, a.buz, a.fiz, type(a) ) )
py 3.0:
('bar', 'brr', 'An attribute', class '__main__.MyNewClass')
py 2.4
('bar', 'brr', 'An attribute', class '__main__.MyNewClass')
Rob.
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Re: asp oddness , why specify ASP twice
davidj411 wrote in news:a08906ab-ba98-4ce0-a5f9-330f4b287423 @z27g2000prd.googlegroups.com in comp.lang.python: for some reason this code works: * %@ LANGUAGE = Python% The above is a Directive, in this case it tells ASP what language to use, but other options like the enocding of the script can be specified. There can only be one directive block It must be the first thing in the asp file and it starts with an @ sign. There is manual, http://msdn.microsoft.com/en-us/library/ms524664.aspx Being MSDN I suggest you read it now as by next week microsoft will have moved the content elsewhere (I'd add a smiley here, but it really isn't funny). % Response.Write (test) % Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Strange output from list
Steve Holden wrote in news:mailman.3804.1226412496.3487.python- [EMAIL PROTECTED] in comp.lang.python: Shouldn't it be GROUP BY master.id? I would have thought that SQL would be sad about a non-aggregate (master.id) that's in the SELECT list but not also in the GROUP BY list. Well, I did say untested. But in SQL Server, for example, any field argument to COUNT() must be an aggregated column. So it may depend on the SQL implementation. I should really have said You must mean an SQL Server other than the Microsofts one, as: select count( aid ) as count from table_1 group by aid count --- 8 8 8 8 8 8 8 8 (8 row(s) affected) and: select count( aid ) as count from table_1 count --- 64 (1 row(s) affected) Like it should. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Exact match with regular expression
Lawrence D'Oliveiro wrote in news:[EMAIL PROTECTED] in comp.lang.python: In message [EMAIL PROTECTED], Rob Williscroft wrote: Read (and bookmark) this: http://www.python.org/doc/2.5.2/lib/re-syntax.html Funny how you never get a thank-you when you tell people to RTFM. Saying Thank You is what email is for, which in this case is what Mr.SpOOn did: Read (and bookmark) this: http://www.python.org/doc/2.5.2/lib/re-syntax.html You want the 3rd item down about the $ special character. Great, thanks. When I read about the symbol in the tutorial I didn't realize what was it for. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Exact match with regular expression
Mr.SpOOn wrote in news:mailman.3069.1225039892.3487.python-
[EMAIL PROTECTED] in comp.lang.python:
Hi,
I'd like to use regular expressions to parse a string and accept only
valid strings. What I mean is the possibility to check if the whole
string matches the regex.
So if I have:
p = re.compile('a*b*')
I can match this: 'aabbb'
m = p.match('aabbb')
m.group()
'aabbb'
But I'd like to get None with this: 'aabb'
Instead it matches the first part:
m = p.match('aabb')
m.group()
'aab'
Read (and bookmark) this:
http://www.python.org/doc/2.5.2/lib/re-syntax.html
You want the 3rd item down about the $ special character.
p = re.compile('a*b*$')
m = p.match('aabb')
m is None
True
m = p.match('aabbb')
m.group()
'aabbb'
Rob.
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Re: Perl/Python regular expressions vs. Boost.regex?
wrote in news:[EMAIL PROTECTED] in comp.lang.python: A colleague wrote a C++ library here at work which uses the Boost.regex library. I quickly discovered an apparent problem with how it searches. Unlike re.match the regex_match function in that library effectively anchors the match at both the start and the end. Can other people confirm this? Thx, Skip Montanaro Quoting from : url:http://www.boost.org/doc/libs/1_36_ 0/libs/regex/doc/html/boost_regex/ref/regex_match.html quote Important Note that the result is true only if the expression matches the whole of the input sequence. If you want to search for an expression somewhere within the sequence then use regex_search. If you want to match a prefix of the character string then use regex_search with the flag match_continuous set. /quote So yes it does. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: ANN: pyparsing 1.5.1 released
Paul McGuire wrote in news:[EMAIL PROTECTED] in comp.lang.python: On Oct 18, 1:05 pm, Terry Reedy [EMAIL PROTECTED] wrote: Paul McGuire wrote: I've just uploaded to SourceForge and PyPI the latest update to (Python 3.0 uses syntax for catching exceptions that is incompatible with Python versions pre 2.6, so there is no way for me to support both existing Python releases and Python 3.0 with a common source code base. I thought 2to3.py was supposed to make that change automatically. Have you tried it and found it not to work? tjr Please re-read my caveat. What I said was (or tried to anyway) was that I cannot write a source file that will work on 2.4, 2.5, 2.6, and 3.0. Actually, it was very close - but for the change in the except syntax, I could actually have pulled it off. I should probably use 2to3.py on my unit tests, so that my Py3 version of pyparsing can get tested more fully. I'll also use 2to3.py on pyparsing.py itself, it will make it easier to maintain the Py3 source version. (I'll still have to keep and support two different source versions though, pity.) AIUI the idea is that you write your 2.x python code (and tests) so that when they are processed by 2to3.py you get valid python 3.x code that will pass all its tests. You then maintain your 2.x code base adding another test where the code (and tests) is run through 2to3.py and then python 3.x runs the test suite. Presumably you only need to start maintining a 3.x code base when you start adding 3.x specific features or abandon support for 2.x python. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: properties access by name
=?KOI8-R?B?7cnU0Q==?= wrote in news:f1a77a69-2997-4f53-9a46-
[EMAIL PROTECTED] in comp.lang.python:
class Film(object):
def __init__(self, title):
self.__title = title
@getproperty
def title(self):
return self.__title
@setproperty
def title(self, value):
self.__title = value
properties_to_set = ['title']
f = Film('aaa')
Ther is a builtin `setattr` to do this:
#http://www.python.org/doc/2.5.2/lib/built-in-funcs.html
setattr( f, title, bbb )
Rob.
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Re: Reading from stdin (in windows)
[EMAIL PROTECTED] wrote in news:mailman.2448.1223974725.3487.python- [EMAIL PROTECTED] in comp.lang.python: Hi! I wanna write a file processor in python (Windows XP). I wanna use pipe, and not parameters. When I write this: ... l = [] while 1: t = sys.stdin.read(1) if t == '': break l.append(t) t = .join(l) ... and use code this: process.py test.txt I got: Bad file descriptor What I do wrong? I need to call this module in another format? Or I read in wrong way? The problem appear to be that MS-Windows doesn't make pipe's for programs it opens via its file type association mechanism. Essentially MS-Windows is treating the .py file as a document and using python to open the document. Try running you program as: python process.py test.txt Note for this to work python will have to be on your path. If it isn't use the full path to you copy of python. for e.g.: c:\python25\python.exe process.py test.txt Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: csv files for download
Bobby Roberts wrote in news:cdc29298-d005-4804-b407-81ecaf6bb1b4@
2g2000hsn.googlegroups.com in comp.lang.python:
I need to be able to offer a client click to download functionality
on their website. Generating the data to provide to them is not an
issue but I want them to be able to click a button and have the
response be sent to a csv file which they are prompted to download.
Can someone point me in the right direction how to do this in python.
Thanks in advance.
Assuming your using WSGI (you don't say) it would be something like this:
def wsgi( environ, start_response ):
start_response( '200 OK', [
('Content-Type','text/csv'),
('Content-Disposition', 'attachment; filename=whatever.csv')
])
...
If your using cgi it will be something like:
print Content-Type: text/csv
print 'Content-Disposition: attachment; filename=whatever.csv'
print
...
http://search.yahoo.com/search?p=Content-Disposition
http://www.python.org/doc/2.5.2/lib/cgi-intro.html
Rob.
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Re: processing email with Python on Windows?
Beliavsky wrote in news:d579f554-be4b-4066-acec-49a7bafb1046 @t41g2000hsc.googlegroups.com in comp.lang.python: I work for a financial company where we run Windows XP and read email using Microsoft Outlook 2003. I get daily files that come as email attachments from various counterparties. I save them as h:\firm_name \mmdd.csv . Would Python be a good tool to automate the process of saving reports, or would it be more convenient to use a Microsoft proprietary language such as VB or C#? Of course one factor is one's relative competence with the various languages. Assuming your Outlook is using Exchange (or at least a IMAP server), you can use imaplib in the standard library. This example should list the messages and attachments in you InBox fot today. EXCHANGE = '' #-- YOUR EXCHANGE SERVER HERE EXCHANGE_PORT = 143 # default USER = '' #-- YOUR USERNAME PWD ='' #-- YOUR PASSWORD import imaplib, email from datetime import date today = date.today().strftime( '%d-%b-%Y' ) imap = imaplib.IMAP4( EXCHANGE, EXCHANGE_PORT ) imap.login( USER, PWD ) imap.select( 'InBox' ) typ, data = imap.search( None, 'SINCE', today ) for num in data[0].split(): typ, data = imap.fetch(num, '(RFC822)') msg = email.message_from_string(data[0][1]) print ( %s, %s\n % ( num, msg['subject'] ) ) for part in msg.walk(): if part.get_filename() is not None: print ( %s\n % part.get_filename() ) imap.close() imap.logout() Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: How do I set a callback in Python?
catsclaw wrote in news:d797403a-e492-403f-933a-bd18ef53d5c0 @k13g2000hse.googlegroups.com in comp.lang.python: I can't for the life of me figure out how to set a callback in Python. I have a class, which wraps another class. The second class needs a callback assigned. I don't want to use globals for it. Here's what I'd like to do: class MyWrapper: def get_login(self, username): return self.user, self.pass def __init__(self, user, pass): self.user = user self.pass = pass self.client = Client(connection string) self.client.callback_login = get_login ... but obviously, the Client class, when it calls the callback, doesn't pass a reference to the self object. How do I do this? use: self.client.callback_login = self.get_login Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Profiling weirdness: Timer.timeit(), fibonacci and memoization
Steven D'Aprano wrote in news:[EMAIL PROTECTED] in comp.lang.python: So the question is: whats going on with timeit.Timer ? As far as I can see, nothing. I think you have misunderstood the results you got. No, the answer is that is it repeats a million times. It might better be called repeat_one_million_times(). Or put another way, myself and the OP misinterpreted what the call t1.repeat( number = 1 ) did. its a confusing API. For the OP: The call t1.timeit() is equivalent to t1.repeat( number = 100 ). So it bennefits from memoization because the call *is* repeated, not just called once like you intended. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Profiling weirdness: Timer.timeit(), fibonacci and memoization
Stefaan Himpe wrote in news:[EMAIL PROTECTED] in comp.lang.python: Nothing weird about this ... The difference will become larger as your input value becomes larger. You can easily understand why if you try to calculate fib(10) by hand, i.e. work through the algorithm with pencil and paper, then compare the work you have to do to the memoized version which just takes fib(9) and fib(8) from memory and adds them together. I think you missed the point. The problem is that the un-decorated, loop only version takes 35 seconds when called by timeit.Timer. However if you apply the decorator it takes less that a second. In *both* cases the function (fib) only gets called once. Note, I timed the call fib(100) with time.clock() and got a value of less than 1 ms, the memozed version takes about 10 times longer. So the question is: whats going on with timeit.Timer ? Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Iterating through 2 files simultaneously
wrote in news:7ae96aff-c1a7-4763-8db7- [EMAIL PROTECTED] in comp.lang.python: Hi folks, I am trying to tee off both stdout and stderr from a process run through Popen. As a test, I am first trying to print the output below: from subprocess import Popen,PIPE ... p1 = Popen(['cvs', 'update'], stdout=PIPE, stderr=PIPE) for (l1, l2) in zip(p1.stdout, p1.stderr): print '--' + l1, print '--' + l2, This doesn't work - probably because I cannot iterate through the pipes this way. I am new to Python, and I'd appreciate it if you could please explain why this doesn't work and/or suggest an alternate way to redirect stdout and stderr to a common place. My objective is for my code to print out stdout/stderr messages and at the same time redirect them to a log file. From the manual url: http://docs.python.org/lib/node528.html: stdin, stdout and stderr specify ... ... Additionally, stderr can be STDOUT, which indicates that the stderr data from the applications should be captured into the same file handle as for stdout. So import STDOUT and make stderr=STDOUT in the Popen call, you will then have one file/pipe to deal with p1.stdout. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Questions on 64 bit versions of Python
Martin v. Löwis wrote in news:[EMAIL PROTECTED] in comp.lang.python: The end result of that is on a 32-bit machine IronPython runs in a 32-bit process and on a 64-bit machine it runs in a 64-bit process. That's probably not exactly true (although I haven't checked). When you start a .NET .exe program, the operating system needs to decide whether to create a 32-bit or a 64-bit process (assuming the processor supports 64-bit mode). The Microsoft .NET commercial framework uses the PE architecture of the Whats the Commercial framework ? I've only come accross 3, the standard 32 bit one and 2 64 bit variants. executable to make that decision (or, rather, it doesn't decide at all, but the underlying OS decides). The C# compiler (more specifically, the assembly linker) offers a choice of setting the .NET architecture to Itanium, AMD64, x86, or any; people use typically any. This any choice is implemented by setting the PE architecture to any, and then indicating to the .NET run-time that any other architecture would be fine as well. As a consequence, an architecture-any executable launches as a 32-bit process on a 64-bit system. I just tested, I built a default C# forms app using the AnyCPU option and it ran as a 64 bit app (no *32 in Task Manager), this is on XP64. I have though installed the AMD64 version of the 2.0 framework and AFAICT neither windows update or the Visual Studio installer will install that by default, you have to go get it your self. To have the executable launch as 64-bit code, you must tell csc.exe to create an AMD64 binary (say), which then means that the binary won't launch on a 32-bit system. I haven't checked, but my guess is that IronPython uses architecture-any executables (unless you adjust the build process). I just started ipy.exe the 1.1 and 2.0B1, both ran as 64 bit processes IronPython 1.1 (1.1) on .NET 2.0.50727.1433 Copyright (c) Microsoft Corporation. All rights reserved. I don't know what happens if you have both 32 bit and 64 bit versions of the framwork installed (presumably with slightly different minor version numbers) as I uninstalled the 32 bit version before I installed the AMD64 version. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Questions on 64 bit versions of Python
Martin v. Löwis wrote in news:[EMAIL PROTECTED] in comp.lang.python: I just tested, I built a default C# forms app using the AnyCPU option and it ran as a 64 bit app (no *32 in Task Manager), this is on XP64. I have though installed the AMD64 version of the 2.0 framework and AFAICT neither windows update or the Visual Studio installer will install that by default, you have to go get it your self. Interesting. I only tested this in .NET 1.1. Perhaps they have changed something since. How exactly did you launch the program? Does it change if you use Python's os.spawn* to launch it? If subprocess.call will do then I can report the same results, a 64 bit process, using 32 bit CPython 2.5 to call it. Also if the programme (C#) is built with the 3.5 framework I get the same results, however interestingly there is no 64 bit build for the 3.5 framework (or at least I was unable to find one). Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: urllib and login with passwords
Jive Dadson wrote in news:[EMAIL PROTECTED] in comp.lang.python: Hey folks! There are various web pages that I would like to read using urllib, but they require login with passwords. Can anyone tell me how to find out how to do that, both in general and specifically for YouTube.com. A typical pattern is submit a form to login and get a cookie back, subsuquent request with the cookie set are then loged in. import cookielib, urllib2 cj = cookielib.CookieJar() opener = urllib2.build_opener( urllib2.HTTPCookieProcessor(cj) ) page = opener.open( LOGIN_URL, data = LOGIN_FORM ) page.close() page = opener.open( DOWNLOAD_URL ) print page.read() page.close() You will need to work out what goes in LOGIN_FORM, it likely something like: LOGIN_FORM = username=namepassword=passsubmit-button=Some+value where username, password and submit-button are the name of the controls on the form you would normally login from. If the form has an enctype='multipart/form-data' then things get a little more complex, possibly start here: http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/146306 Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: is there a bug in urlunparse/urlunsplit
Alex wrote in news:09764c57-03ce-4ccb-a26d-
[EMAIL PROTECTED] in comp.lang.python:
Hi all.
Is there a bug in the urlunparse/urlunsplit functions?
Look at this fragment (I know is quite silly):
urlunparse(urlparse('www.example.org','http'))
--- 'http:///www.example.org'
^
Try these 3:
urlparse('www.example.org','http')
urlparse('http://www.example.org','http')
urlparse('//www.example.org','http')
The 1st returns www.example.org as the path part
with the other 2 its the location (domain) part.
Although it may not be immediately obvious that the result
is correct, consider the follwing html fragment:
img src=aaa.gif
img stc=http://anothersite.com/bbb.gif;
If you were to use urlparse to parse the src attributes
you would want:
( '', '', 'aaa.gif', '','','' )
( 'http', 'anothersite.com', '/bbb.gif', '','','' )
Which AIUI is what urlparse does.
Rob.
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Re: https and POST method
Lorenzo Stella wrote in news:7956f925-1037-49ea-a360-b58d627ffb20 @z24g2000prf.googlegroups.com in comp.lang.python: Hi all, I'm trying to write a simple script for sending sms via vyke... I have to make a https connection and pass some data with the POST method, like this perl script does: Curl maybe, http://pycurl.sourceforge.net/ Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: encoding/decoding issue with python2.5 and pymssql
Tzury Bar Yochay wrote in news:3a6c32fe-e7c1-4230-882d-efb3415196c1 @b1g2000hsg.googlegroups.com in comp.lang.python: for example: the value 'EE604EE3-4AB0-4EE7-AF4D-018124393CD7' is represent as '\xe3N`\xee\xb0J\xe7N\xafM\x01\x81$9\xd7' from uuid import * u = UUID( bytes = '\xe3N`\xee\xb0J\xe7N\xafM\x01\x81$9\xd7') print u u = UUID( bytes_le = '\xe3N`\xee\xb0J\xe7N\xafM\x01\x81$9\xd7') print u The bytes_le version prints: ee604ee3-4ab0-4ee7-af4d-018124393cd7 so I guess, this is what mysql is returning. http://docs.python.org/lib/module-uuid.html Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Cost of unicode(s) where s is Unicode
John Nagle wrote in news:[EMAIL PROTECTED] in comp.lang.python: Does text = unicode(text) make a copy of a Unicode string, or is that essentially a free operation if the input is already Unicode? John Nagle http://docs.python.org/lib/built-in-funcs.html#l2h-78 ... More precisely, if object is a Unicode string or subclass it will return that Unicode string without any additional decoding applied. ... Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Who's to blame?
Nicola Musatti wrote in news:92dfc2fc-0677-43c0-b34f-4f240fa40205 @e4g2000hsg.googlegroups.com in comp.lang.python: Note there is a wxpython mailinglist/newsgroup: news:gmane.comp.python.wxpython [snip] problem lies in the fact that apparently ShowModal() does not return when either the Yes or the No buttons are pressed. Curiously, if you change the Yes and No buttons with the OK and Cancel ones that are currently commented everything works as expected. This is because the wx.Dialog class has handlers for the wxID_OK and wxID_CANCEL button identifiers, IIRC in windows the MS supplied dialog procedure behaves this way. As the sbs_test_xrc.py file below is automatically generated by wxPython 2.8.6.1's XRCed tool from a XRC file which in turn is generated by wxFormBuilder (http://wxformbuilder.org/), I really cant figure out to whom I should report this problem, assuming I'm not missing some obvious mistake of mine, that is. class MainFrame(sbs_test_xrc.xrcMainFrame): def __init__(self, parent): sbs_test_xrc.xrcMainFrame.__init__(self, parent) self.button.Bind(wx.EVT_BUTTON, self.OnButton) First you can make the dialog a member, you are showing and hiding it so there is no need to create a new one every time OnButton is fired. self.dialog = sbs_test_xrc.xrcDialog(self) # now replace the defaults of ID_OK and ID_CANCEL # self.dialog.SetAffirmativeId( wxID_YES ) self.dialog.SetEscapeId( wxID_NO ) Alternativly you could derive from xrcDialog as you are with xrcMainFrame and do the above in the derived classes __init__. def OnButton(self, event=None): d = sbs_test_xrc.xrcDialog(self) ##if d.ShowModal() == wx.ID_OK: if d.ShowModal() == wx.ID_YES: self.Close() http://www.wxpython.org/docs/api/wx.Dialog-class.html Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Extracting files from an ISO image?
Ant wrote in news:34a84caa-5387-40a2-a808- [EMAIL PROTECTED] in comp.lang.python: [snip] So I have two questions really: 1) Is there a module out there for extracting files from an ISO? There are command line programs that can do this: http://cdrecord.berlios.de/old/private/cdrecord.html This (with isoinfo.exe from the above) will list all files in an iso image file: CD = path-to-iso import subprocess subprocess.call( [ isoinfo.exe, '-f', '-i', CD ] ) isoinfo.exe also has a switch to extract a file to stdout One problem you may have is daemon tools will mount cd images that aren't iso images, where as isoinfo appears to handle only genuine iso file systems. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: mysqldb SELECT COUNT reurns 1
SMALLp wrote in news:[EMAIL PROTECTED] in comp.lang.python: Hy! I nave another problem I can't solve! code import MySQLdb as mysql cursor = conn.cursor() sql = SELECT COUNT(*) FROM + dataTable res = cursor.execute(sql) I think you need to do: res = cursor.fetchone()[0] print res code It prints 1, and there are 88 rows in table. SELECT works fine, but SELECT COUNT(*) makes problems. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Connecting to SQL database
bill ramsay wrote in news:[EMAIL PROTECTED] in
comp.lang.python:
Hi
I have successfully connected to SQL2000 and MSDEE databases in the
Conn = Dispatch('ADODB.Connection')
Conn.ConnectionString = Provider=SQLNCLI;Server=10.1.1.2;
Database=csrctest;Uid=bill;Pwd=bill
By default SQL 2005 doesn't enable the TCP/IP protocol, if your app'
is running on the same machine use either the machine name or a
period (.) and it will use the Shared Memory protocol.
You will also need the server instance name(*), so it would be:
Provider=SQLNCLI;Server=.\SQLEXPRESS;Datab...
*) IIRC you can't install express as the Default instance so
this will be required.
If you need to enable TCP/IP use the SQL Server Configuration Manager
about 4 levels deep from the Start menu. Remember to enable it for
the server and SQLNCLI.
Rob.
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Re: I want py2exe not to create library.zip
On Wed, 12 Sep 2007 22:09:30 +0200, Laszlo Nagy wrote: Hi, I want py2exe not to create library.zip. My reason is that the installed program will be a self updating program, and it must be able to download changes (newer python source files) from the server. So the files should not be in library.zip. I tried the --bundle option but apparently it can only be used to make the distribution __more__ bundled. In your setup.py, after the call to setup(), use zipfile.ZipFile to extract the library.zip into a directory called library then delete the .zip. I can't remember of the top of my head, but you may actually need to rename the new directory to library.zip for your application to work. -- Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Get the current date, python 2.2
On Fri, 15 Jun 2007 14:30:36 -0700, nano wrote: Using python 2.2 what is the simplest way to get the current date value? I have looked in so many places. The question is often asked and the usual response indicates how to get the current date and time like now = time.localtime() I want just the date, like 2007-06-15. The value will go into a postgresql Date type column. import datetime d = datetime.date.today() d.isoformat() '2007-06-15' Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Get the current date, python 2.2
On Fri, 15 Jun 2007 14:46:20 -0700, nano wrote: In article [EMAIL PROTECTED], [EMAIL PROTECTED] says... On Fri, 15 Jun 2007 14:30:36 -0700, nano wrote: Using python 2.2 what is the simplest way to get the current date value? I have looked in so many places. The question is often asked and the usual response indicates how to get the current date and time like now = time.localtime() I want just the date, like 2007-06-15. The value will go into a postgresql Date type column. import datetime d = datetime.date.today() d.isoformat() '2007-06-15' Rob. Thanks, I'd read that today() was only good for 2.3? Right I missed that, though its actually the datetime module that is new in 2.3. This should do though: import time time.strftime( %Y-%m-%d ) '2007-06-15' -- Rob. -- http://mail.python.org/mailman/listinfo/python-list
Re: Connection acception with confirmation
no`name` wrote in news:[EMAIL PROTECTED] in comp.lang.python: maybe someone have some ideas how to block first stdin in main function and get stdin from the thread when here is a new connection? No, but you could instead use a Queue: http://docs.python.org/lib/module-Queue.html so that your main thread reads stdin and then uses an instance of Queue to post the 'y's and 'n's it recives to your server thread. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Is wsgi ready for prime time?
Ron Garret wrote in news:rNOSPAMon-B77D6B.12263417052007 @news.gha.chartermi.net in comp.lang.python: PACKAGE CONTENTS handlers headers simple_server util validate Reading the documentation can be useful sometimes. Recommending http://docs.python.org/lib/module-wsgiref.html, too. I did read the documentation, but the documentation does not seem to reflect reality, e.g.: wsgiref.util Traceback (most recent call last): File stdin, line 1, in module AttributeError: 'module' object has no attribute 'util' IDLE 1.2 import wsgiref.util wsgiref.util module 'wsgiref.util' from '\Python25\lib\wsgiref\util.pyc' Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Interesting list Validity (True/False)
wrote in news:[EMAIL PROTECTED] in comp.lang.python: [] == [] True ['-o'] == [] False ['-o'] == False False To test wether something is true use if. To test wether something is false use if not. The python values True and False are for when you need to *store* a boolean value (for later testing). I you want to to see if an arbitry expression would test as true or false at the interactive prompt use bool(): bool([]) False bool(['-o']) True There is *never* any need to write things like: expression == True or: expression == False Once you stop doing this things will become much simpler. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: tkinter get widget option value
wrote in news:[EMAIL PROTECTED] in comp.lang.python: If I have a button widget w = Button(root, text = Button, state = 'disabled') How can I get the value of option 'state' from the widget 'w'. I want something like -- print w.state to print out 'disabled' print w.cget( state ) Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Error when using Custom Exception defined in a different python module.
wrote in news:[EMAIL PROTECTED] in comp.lang.python: Hi, I am hitting this error consistently and don't know why it's happening. I would like to define all exceptions for my project in one file and use them across the project. Here's a sample - exceptions.py - from exceptions import * raise MyException(Raise custom error) When the above is run, I get the following error - NameError: global name 'MyException' is not defined When you get this kind of error, goto a python prompt (type python at a command prompt, or click on IDLE) and try this: import exceptions help( exceptions ) I got this response (clipped): Help on built-in module exceptions: NAME exceptions - Python's standard exception class hierarchy. Another common module name to avoid is test. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: How do I use the config parser?
wrote in news:[EMAIL PROTECTED] in comp.lang.python: Hi, I need a specific example. I have seen the docs, but I don't all the stuffs there. from ConfigParser import ConfigParser Now I want to know how to read a section, a section attribute's value, and to write thoses back after reading. ConfigParser is derived from RawConfigParser, so you need to look at RawConfigParser's docs here: http://docs.python.org/lib/RawConfigParser-objects.html Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Why does not my wx.html.HtmlWindow work?
[EMAIL PROTECTED] wrote in news:[EMAIL PROTECTED] in comp.lang.python: Below are my source code: import wx import wx.html class MyHtmlFrame(wx.Frame): def __init__(self, parent, title): wx.Frame.__init__(self, parent, -1, title, size=(600,400)) html = wx.html.HtmlWindow (self) if gtk2 in wx.PlatformInfo: html.SetStandardFonts() html.LoadPage( http://www.pythonthreads.com/articles/python/incorporating-into -wxpython-part-1.html) app = wx.PySimpleApp() frm = MyHtmlFrame(None, Simple HTML Browser) frm.Show() app.MainLoop() It is just an example in the book wxPython in action. But every time when I try to get it run, my CPU is fully occupied, and there is no frame that comes into existence. Why? I think your problem is that you call LoadPage before app.MainLoop() is called, IOW you need to call LoadPage in an event handler: import wx import wx.html class MyHtmlFrame(wx.Frame): HOME = http://www.google.co.uk; def __init__(self, parent, title): wx.Frame.__init__(self, parent, -1, title, size=(600,400)) self.html = wx.html.HtmlWindow (self) if gtk2 in wx.PlatformInfo: self.html.SetStandardFonts() self.done_show = False wx.EVT_IDLE( self, self.OnShow ) self.html.SetPage( a href='%s'Loading .../a % self.HOME ) def OnShow( self, event ): if self.done_show: return self.done_show = True self.html.LoadPage( self.HOME ) app = wx.PySimpleApp() frm = MyHtmlFrame(None, Simple HTML Browser) frm.Show() app.MainLoop() Note: the URL you loading takes ages to show, which is why I use: http://www.google.co.uk above. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: where to find wx package
siggi wrote in news:[EMAIL PROTECTED] in comp.lang.python: Hi all, a newbie question: I have a program gui03A.py using wxPython, importing it such: from wxPython.wx import * The program works, but I get the warning message: gui03A.py:4: DeprecationWarning: The wxPython compatibility package is no longer automatically generated or activly maintained. Please switch to the wx package as soon as possible. However, after extensive searching on www.python.org and Googling the web, I do not find any package with wx as its only name. Where can I get the wx package (for win32 XP)? The wx package talked about above is also part of WxPython, so you have already got it. To import it use: import wx You will need to translate all (well most) identifiers in your programme from wxBlah to wx.Blah so: class MyFrame( wxFrame ): pass becomes class MyFrame( wx.Frame ): pass Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: method names in __slots__ ??
John Machin wrote in news:1167008799.074885.250770@ 73g2000cwn.googlegroups.com in comp.lang.python: Given a = Adder(), a.tally = 0 gets AttributeError: 'Adder' object attribute 'tally' is read-only a.notinslots = 1 gets AttributeError: 'Adder' object attribute 'notinslots' is read-only So is there some magic class-fu going down here, or is this just a waste of memory space in the instances? Haven't you, with your 2 examples above, answered your own question ? Clearly from your example it doesn't make any difference if you add a class attribute to the slots, one way or another its as if you hadn't put it in there in the first place. This will give the same error, which shows its about class attributes and not just methods: class Adder(object): __slots__ = [ 'class_name' ] class_name = 3 a = Adder() a.class_name = 2 It would seem that the interpreter removes any names it finds as class attribute names from the list it finds in __slots__ before it creates the instance. Of course if my guessing above isn't good enough, we could look at the documentation: http://docs.python.org/ref/slots.html#l2h-218 __slots__ are implemented at the class level by creating descriptors (3.4.2) for each variable name. As a result, class attributes cannot be used to set default values for instance variables defined by __slots__; otherwise, the class attribute would overwrite the descriptor assignment. So its that the __slots__ assignment makes the descriptors and then the subsiquent method defenitions and class attribute bindings remove them. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: method names in __slots__ ??
John Machin wrote in news:[EMAIL PROTECTED] in comp.lang.python: Rob Williscroft wrote: John Machin wrote in news:1167008799.074885.250770@ 73g2000cwn.googlegroups.com in comp.lang.python: Given a = Adder(), a.tally = 0 gets AttributeError: 'Adder' object attribute 'tally' is read-only a.notinslots = 1 gets AttributeError: 'Adder' object attribute 'notinslots' is read-only So is there some magic class-fu going down here, or is this just a waste of memory space in the instances? Haven't you, with your 2 examples above, answered your own question ? No. Clearly from your example it doesn't make any difference if you add a class attribute to the slots, one way or another its as if you hadn't put it in there in the first place. Clearly? Not so. It takes up memory. A list of 1 million Adder instances takes up about 68 Mb (Python 2.5 on Windows XP). With the method names removed from the __slots__, it takes only about 44 Mb. [For comparison: with no __slots__ at all, it takes about 180 Mb] 68 - 44 = 24 24 / 4 = 6 So thats 6 pointers for 5 methods, probably 5 pointers and and 4 bytes round up to the nearest allocation unit. So the slots in the instance are staying arround, even though they are no longer accesable (see below). [snip] It would seem that the interpreter removes any names it finds as class attribute names from the list it finds in __slots__ before it creates the instance. It doesn't seem so to me. If it did that, the memory usage would not increase. It was a guess, and an incorrect guess, but thats why I quoted the docs below. Of course if my guessing above isn't good enough, we could look at the documentation: http://docs.python.org/ref/slots.html#l2h-218 __slots__ are implemented at the class level by creating descriptors (3.4.2) for each variable name. As a result, class attributes cannot be used to set default values for instance variables defined by __slots__; otherwise, the class attribute would overwrite the descriptor assignment. I have read that, before I posted. Asides: (1) It would be useful if it stated the empirically determined fact that the result is that the class attribute is thusly made read-only. (2) The second sentence is not a model of clarity. In any case I can't see how the paragraph gives any support for your next statement: So its that the __slots__ assignment makes the descriptors and then the subsiquent method defenitions and class attribute bindings remove them. Errrmmm ... if the descriptors are removed, how is it that the behaviour is read-only? The descriptors are part of the class object, they are removed when the class attributes are rebound, further rebinding of the class attributes will work fine: Adder.tally = 0 They are not assignable in the instance as the class descriptors that would have forwarded the assignment to the instances slots have been replaced. The memory usage is higher because the slots in the instance are still there even though the descriptors that would allow them to be assigned have been removed. Rob. -- http://www.victim-prime.dsl.pipex.com/ -- http://mail.python.org/mailman/listinfo/python-list
