Re: urllib2 - iteration over non-sequence

[Gabriel Genellina]

En Sun, 10 Jun 2007 02:54:47 -0300, Erik Max Francis <[EMAIL PROTECTED]>  
escribió:

> Gary Herron wrote:
>
>> Certainly there's are cases where xreadlines or read(bytecount) are
>> reasonable, but only if the total pages size is *very* large.  But for
>> most web pages, you guys are just nit-picking (or showing off) to
>> suggest that the full read implemented by readlines is wasteful.
>> Moreover, the original problem was with sockets -- which don't have
>> xreadlines.  That seems to be a method on regular file objects.
>>
> There is absolutely no reason to read the entire file into memory (which
> is what you're doing) before processing it.  This is a good example of
> the principle of there is one obvious right way to do it -- and it isn't
> to read the whole thing in first for no reason whatsoever other than to
> avoid an `x`.

The problem is -and you appear not to have noticed that- that the object  
returned by urlopen does NOT have a xreadlines() method; and even if it  
had, a lot of pages don't contain any '\n' so using xreadlines would read  
the whole page in memory anyway.

Python 2.2 (the version that the OP is using) did include a xreadlines  
module (now defunct) but on this case it is painfully slow -  
perhaps it tries to read the source one character at a time.

So the best way would be to use (as Paul Rubin already said):

for line in iter(lambda: f.read(4096), ''): print line

-- 
Gabriel Genellina

-- 
http://mail.python.org/mailman/listinfo/python-list

Re: DAO and Access97 WHERE clause fails

[stefaan]

> I should point out that I don't do DAO (or ADO) -- and if I had to
> code Python to access JET, I'd probably hijack a copy of mxODBC in order
> to get a "sane" SQL interface.

I have successfully used the dejavu object-relational mapper (http://
projects.amor.org/docs/dejavu/1.5.0RC1/) to access MS ACCESS databases
recently.

Bestregards,
Stefaan.

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Re: PyGTK : a NEW simple way to code an app

[James T. Dennis]

manatlan <[EMAIL PROTECTED]> wrote:
> I was a fan of "SimpleGladeApp/tepache way" to build a pygtk app.
> I've build a new efficient/dynamic way to build a pygtk app ...

> Here is an example :
> =
> class Fen(GladeApp):
>"""
>Window win
>.title="Hello"
>@delete_event
>VBox
>HBox
>Label jo
>.label="kokotte"
>entry myEntry
>.text="kuku"
>gtkBuTTon b2
>.label="33"
>@clicked
>Label jo
>.label="koko"
>Button b
>.label="3"
>@clicked
>"""
>def init(self,m):
>self.jo.set_text(m)
>pass
>def on_b_clicked(self,*a):
>self.quit(3)
>def on_b2_clicked(self,*a):
>self.quit(33)
>def on_win_delete_event(self,*args):
>self.quit(4)

> f=Fen("koko2")
> print f.loop()
> =

> How it works :

> in fact, the __doc__ is converted as a "glade file"
> the tree of object is indented (like python way)
> you can see some common pygtk widget ...
> line starting with a dot is an property of the parent object.
> line starting with a @ is a declaration of a event of the parent
> object.
> widgets are not case sensitive, and can start with "Gtk". If a second
> word is provided it will be used as an "id", otherwise an unique id
> will be build according the type of widget.
> the window is created with glade, widgets are provided as attributs of
> the instance, and signals are autoconnected on method
> "on_[widgetId]_[event](self,*args)" (if a signal is missing in your
> class, it warns you at run time) 

> It will not replace the use of glade-3 for complex widget ... but I
> think it's an easy way to code very easily/quickly a simple pygtk
> window/form.
> I think it could be really useful/handly for beginners too.

> for people which are involved in pygtk/python/gui ... i'd like to hear
> your comments/ideas ...

> Rq:
> i don't provide the code now, but it will be released in next version
> of "GladeApp" ( http://manatlan.infogami.com/GladeApp )
> it works already, but i need to make "packing properties available"
> too ...

 I'd be a little leery of overloading the __doc__ strings in this
 way.  (They are overloaded enough when used for doctest strings ...
 but those can serve a legitimate documentary purpose and other doctests
 can be stored separately).

 Perhaps it would make sense to standardize on a defined member name
 such as: GTK__Glade.  The rest of your code could remain the same.

 Are there any other Python projects using other "magically introspected
 strings" approaches?  I thought I saw something being used by some 
 "programming by contract" or some AOP (aspect oriented programming) tools
 that might be using something like this.


-- 
Jim Dennis,
Starshine: Signed, Sealed, Delivered

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Re: Third-party libs in version control

[Marc 'BlackJack' Rintsch]

In <[EMAIL PROTECTED]>, Marcus wrote:

> I'm new to developing large subversion-controlled projects. This one
> will involve a few third-party libraries like wxWidgets, and perhaps
> Twisted. Ordinarily you could just install these into your system and
> they'll end up globally (in Python's Lib/site-packages directory). Is it
> proper practice to instead install the libraries into a separate [vendor
> branch] of the repository and reference that instead?
> 
> I've read about vendor branches, and I'm under the impression that
> you're supposed to do that /instead/ of installing the libraries
> globally into Python's subdirectories... is that correct?

I think that's not the "normal" way.  Vendor branches are useful if you
want *exactly* one version if a third party product.  That might be
important if their API is a rapidly moving target or newer versions
changed much, or have critical bugs.  Another use case is modifying the
external sources.  Then it's of course a good idea to put the vanilla
sources under version control to be able to merge updates from the vendor
into the modified branch.

Do you ship all that third party stuff with your project?

Last but not least I'm using subversion nearly exclusively for source
code IOW not for compiled code.  Checking in an installed wxWidgets or
wxPython alongside some source code "feels" a little strange to me.  Pure
Python code might be okay but if there are external dependencies one can't
checkout on another computer and expect everything to work there.

Ciao,
Marc 'BlackJack' Rintsch
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Re: urllib2 - iteration over non-sequence

[Erik Max Francis]

Paul Rubin wrote:

> If you know in advance that the page you're retrieving will be
> reasonable in size, then using readlines is fine.  If you don't know
> in advance what you're retrieving (e.g. you're working on a crawler)
> you have to assume that you'll hit some very large pages with
> difficult construction.

And that's before you even mention the point that, depending on the 
application, it could easily open yourself up to a DOS attack.

There's premature optimization, and then there's premature completely 
obvious and pointless waste.  This falls in the latter category.

Besides, someone was asking for/needing an older equivalent to iterating 
over a file.  That's obviously .xreadlines, not .readlines.

-- 
Erik Max Francis && [EMAIL PROTECTED] && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
   The more violent the love, the more violent the anger.
-- _Burmese Proverbs_ (tr. Hla Pe)
-- 
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Re: urllib2 - iteration over non-sequence

[Erik Max Francis]

Gary Herron wrote:

> Certainly there's are cases where xreadlines or read(bytecount) are
> reasonable, but only if the total pages size is *very* large.  But for
> most web pages, you guys are just nit-picking (or showing off) to
> suggest that the full read implemented by readlines is wasteful. 
> Moreover, the original problem was with sockets -- which don't have
> xreadlines.  That seems to be a method on regular file objects.
> 
>  For simplicity, I'd still suggest my original use of readlines.   If
> and when you find you are downloading web pages with sizes that are
> putting a serious strain on your memory footprint, then one of the other
> suggestions might be indicated.

It isn't nitpicking to point out that you're making something that will 
consume vastly more amounts of memory than it could possibly need.  And 
insisting that pages aren't _always_ huge is just a silly cop-out; of 
course pages get very large.

There is absolutely no reason to read the entire file into memory (which 
is what you're doing) before processing it.  This is a good example of 
the principle of there is one obvious right way to do it -- and it isn't 
to read the whole thing in first for no reason whatsoever other than to 
avoid an `x`.

-- 
Erik Max Francis && [EMAIL PROTECTED] && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
   The more violent the love, the more violent the anger.
-- _Burmese Proverbs_ (tr. Hla Pe)
-- 
http://mail.python.org/mailman/listinfo/python-list

Re: 4 byte integer

[James T. Dennis]

Paul D Ainsworth <[EMAIL PROTECTED]> wrote:
> Greetings everyone. I'm a relative newcomer to python and I have a technical 
> problem.

> I want to split a 32 bit / 4 byte unsigned integer into 4 separate byte 
> variables according to the following logic: -

> bit numbers 0..7 byte 1
> bit numbers 8..15 byte 2
> bit numbers 16..23 byte 3
> bit numbers 24..31 byte 4

> Each of these byte variables to contain integer data from 0 to 255 (or 0 to 
> FF in hex mode)

> I had thought that struct.unpack with an input message format of 'I' would 
> be the way to do it, but its reporting an error that it doesn't want to 
> accept an integer.

> Please can anyone advise?

 Would something like this work?

def word2bytes(n):
"""Given an positive integer n, return a tuple of 4 bytes from 
   n's least significant 32-bits
"""
r = []
n &= 0xL
for i in range(4):
r.append(n & 0xFF)
n >>= 8
r.reverse()
return tuple(r)

 





-- 
Jim Dennis,
Starshine: Signed, Sealed, Delivered

-- 
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Re: Bug/Weak Implementation? popen* routines can't handle simultaneous read/write?

[Nick Craig-Wood]

dmoore <[EMAIL PROTECTED]> wrote:
>  On Jun 8, 12:30 pm, Nick Craig-Wood <[EMAIL PROTECTED]> wrote:
> > Windows has a really strange idea of non-blocking IO - it uses
> > something called overlapped io.  You or in the FILE_FLAG_OVERLAPPED
> > flag when you create the file/pipe.  You then pass in overlap buffers
> > for reading writing.
> >
> 
>  the wx guys appear to do it differently (unless FILE_FLAG_OVERLAPPED
>  is implicit in the calls they make)
> 
>  take a look at:
>  
> http://cvs.wxwidgets.org/viewcvs.cgi/wxWidgets/src/msw/utilsexc.cpp?rev=1.88&content-type=text/vnd.viewcvs-markup
> 
>  a reasonably well-documented wxExecute function handles all the messy
>  win32 api calls and wraps the process in a wxProcess object and the
>  streams in wxInputStream / wxOutputStream (also see the wxExecuteDDE
>  function)

You are right, named pipes seem to have a non blocking mode.

Here is the lowdown from
http://msdn2.microsoft.com/en-US/library/aa365605.aspx

  Both pipe clients and pipe servers can change a pipe handle's wait
  mode by specifying either PIPE_WAIT or PIPE_NOWAIT in a call to the
  SetNamedPipeHandleState function.

  Note The nonblocking-wait mode is supported for compatibility with
  Microsoft® LAN Manager version 2.0. This mode should not be used to
  achieve overlapped input and output (I/O) with named
  pipes. Overlapped I/O should be used instead, because it enables
  time-consuming operations to run in the background after the
  function returns. For more information about overlapped I/O, see
  Synchronous and Overlapped Input and Output.

So it has a nonblocking mode but you shouldn't use it!

-- 
Nick Craig-Wood <[EMAIL PROTECTED]> -- http://www.craig-wood.com/nick
-- 
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Re: urllib2 - iteration over non-sequence

[Paul Rubin]

Gary Herron <[EMAIL PROTECTED]> writes:
>  For simplicity, I'd still suggest my original use of readlines.   If
> and when you find you are downloading web pages with sizes that are
> putting a serious strain on your memory footprint, then one of the other
> suggestions might be indicated.

If you know in advance that the page you're retrieving will be
reasonable in size, then using readlines is fine.  If you don't know
in advance what you're retrieving (e.g. you're working on a crawler)
you have to assume that you'll hit some very large pages with
difficult construction.


-- 
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Re: read xml file from compressed file using gzip

[flebber]

On Jun 10, 3:45 am, Stefan Behnel <[EMAIL PROTECTED]> wrote:
> flebber wrote:
> > I was working at creating a simple program that would read the content
> > of a playlist file( in this case *.k3b") and write it out . the
> > compressed "*.k3b" file has two file and the one I was trying to read
> > was maindata.xml
>
> The k3b format is a ZIP archive. Use the zipfile library:
>
> file:///usr/share/doc/python2.5-doc/html/lib/module-zipfile.html
>
> Stefan

Thanks for all the help, have been using the docs at python.org and
the magnus t Hetland book. Is there any docs tha re a little more
practical or expressive as most of the module documentation is very
confusing for a beginner and doesn't provide much in the way of
examples on how to use the modules.

Not criticizing the docs as they are probably very good for
experienced programmers.

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Re: MI5 Persecution: Goldfish and Piranha 29/9/95 (5104)

[Mike]

And this is here because ???


<[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
|I just thought I'd let you know what I've been reading into 
the
| "Crusader" spam. I don't want to post this to usenet 
because somebody
| might try to tie that in to my posts in some way (someone 
already has, in
| uk.misc).
|
| First of all, I'd like to ask you to believe that my phone 
line in my
| apartment is bugged, and has been for many months. I have 
moved a couple
| of times this year, but "they" have faithfully been on my 
trail.
|
| Anyway, let's suppose my phone line is bugged. Now, when I 
talk to my
| internet service provider, it's over a SLIP (now PPP) 
connection. So if
| you wanted to bug what was said, either you'd listen in 
over the line and
| have to decode the transmission, or you could go to the 
service provider
| (more difficult) and ask them to decode a particular 
user's connection.
|
| OK, so now they're listening to everything I do over my 
SLIP/PPP
| connection. A couple of months ago I was messing around 
with faking
| articles through nntp servers and through anonymous 
remailers. I chose a
| nice inconspicuous newsgroup for my little tests, 
something no-one would
| ever notice. Guess which newsgroup I chose??? Yes, 
_FISH_!!! or
| rec.aquaria to be precise
|
| And guess what articles I tried to post? Goldfish, Koi 
carp and, you'll
| never guess... PIRANHA!!! The goldfish article and the Koi 
went through,
| but the piranha didn';t appear.
|
| by now you probably think this is too silly for words. But 
if you look in
| the papers a few eeks ago you will find John Major, Tonny 
Blair and Paddy
| Ashdown sharing a "private joke" about Major's sunburnt 
goldfish. We
| haven't had anything about Koi yet (they must be too 
dull ). Now, sent by
| someone who clearly knew what they were doing (they chose 
an Italian
| backbone site for their launch point) we have many 
thousands of messages
| to people all over the globe. All about piranha, and with 
the punchline
| "that gives you something to think about, doesn't it?"
|
| The way it works is that they're trying to kill two birds 
with one stone
| again. I don't knoiw why they should be against these 
national alliance
| people, but my interpretation is that they simultaneously 
try to
| discredit them, and stem the flow of Corley articles.
|
| 
=
|
| In article <[EMAIL PROTECTED]>,
| Mike Corley <[EMAIL PROTECTED]> wrote:
| >
| >John J Smith ([EMAIL PROTECTED]) wrote:
| >
| >: b) we do know who you are. Or are you someone else we 
don't know about?
| >: You are currently known as "That bloody persistant net 
nutter, who's
| >: expanding from uk.misc to the rest of the world".
| >
| >I think the point I was trying to make is that I could 
tell you things
| >from my personal life, at home and at work, which would 
add credibility
| >to my story. But if I named people, then (a) they would 
object violently
| >to being included in this shenanigans, and (b) I would be 
revealing my
| >identity which would be bad for my personal life and my 
work life. Of
| >course some people in my personal life, and at work, do 
know who "mike
| >corley" is. But at least we're observing a studied 
silence for now.
|
| :People can always be called "MR X", to save them being 
named.
| :
| :I'm completely perplexed as to what you mean by b). 
Revealing identity?
| :To who? And why would this be bad for any part of your 
life when you
| :already have a less than respectful reputation here?
|
| I'll just enumerate one or two things that I can still 
remember. Sometime
| around August/Sept 1992 I was living in a house in Oxford, 
and coming out
| of the house was physically attacked by someone - not 
punched, just grabbed
| by the coat, with some verbals thrown in for good measure. 
That was something
| the people at work shouldn't have known about... but soon 
after a couple of
| people were talking right in front of me about, "yeah, I 
heard he was
| attacked".
|
| Again, one I went for a walk in some woods outside Oxford. 
The next day,
| at work, someone said "you know he went to the forest 
yesterday".
|
| I don't want to put details on usenet of what happened 
because to do so
| would be to risk it happening again. If you put ideas in 
peoples' heads
| then you can find them reflecting back at you, and I don't 
want that.
| Also I can't remember that much from three years ago. From 
november 1992
| I started taking "major tranquilizers" and just blotted 
the whole thing
| from my mind.
|
| >This is a feature time and time again, that the security 
services
| >(presumed) get at you by manipulating other people around 
you to get at
| >you. If you have their contacts, manpower, resources and 
technology then
| >you can do that sort of thing.
|
| :But why? Are you a threat?
|
| They pretend they "have" to get at me. After the first few 
weeks they had
| to find a reason to spy and abuse. Yo

Re: The Concepts and Confusions of Prefix, Infix, Postfix and Fully Functional Notations

[Twisted]

On Jun 9, 8:21 pm, "BCB" <[EMAIL PROTECTED]> wrote:
> "Paul McGuire" <[EMAIL PROTECTED]> wrote in message
>
> news:[EMAIL PROTECTED]
>
> > On Jun 9, 6:49 am, Lew <[EMAIL PROTECTED]> wrote:
> >> > In particular, Perl code looks more like line
> >> > noise than like code from any known programming language. ;))
>
> >> Hmm - I know of APL and SNOBOL.
>
> >> --
> >> Lew
>
> > TECO editor commands.  I don't have direct experience with TECO, but
> > I've heard that a common diversion was to type random characters on
> > the command line, and see what the editor would do.
>
> > -- Paul
>
> J
>
> http://www.jsoftware.com/

Oh come on! Toy languages (such as any set of editor commands) and
joke languages (ala Intercal) don't count, even if they are
technically Turing-complete. ;)

Nor does anything that was designed for the every-character-at-a-
premium punch-card era, particularly if it is, or rhymes with,
"COBOL".

Those have excuses, like it's a joke or it's a constrained
environment. Perl, unfortunately, has no such excuses. If there were
such a thing as "embedded Perl", I'd have to hesitate here, but since
there isn't...

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Re: urllib2 - iteration over non-sequence

[Gary Herron]

Paul Rubin wrote:
> Erik Max Francis <[EMAIL PROTECTED]> writes:
>   
>> This is really wasteful, as there's no point in reading in the whole
>> file before iterating over it.  To get the same effect as file
>> iteration in later versions, use the .xreadlines method::
>>
>>  for line in aFile.xreadlines():
>>  ...
>> 
>
> Ehhh, a heck of a lot of web pages don't have any newlines, so you end
> up getting the whole file anyway, with that method.  Something like
>
>for line in iter(lambda: aFile.read(4096), ''): ...
>
> may be best.
>   
Certainly there's are cases where xreadlines or read(bytecount) are
reasonable, but only if the total pages size is *very* large.  But for
most web pages, you guys are just nit-picking (or showing off) to
suggest that the full read implemented by readlines is wasteful. 
Moreover, the original problem was with sockets -- which don't have
xreadlines.  That seems to be a method on regular file objects.

 For simplicity, I'd still suggest my original use of readlines.   If
and when you find you are downloading web pages with sizes that are
putting a serious strain on your memory footprint, then one of the other
suggestions might be indicated.

Gary Herron




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Re: Seattle Python Interest Group meeting 7 PM Thursday

[James Thiele]

On Jun 9, 8:35 pm, James Thiele <[EMAIL PROTECTED]> wrote:
> Seattle Python Interest Group meeting 7 PM Thursday 14 June 2007.
>
> Seehttp://www,seapig.orgfor location and directions.

Ooops!
http://www.seapig.org

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Seattle Python Interest Group meeting 7 PM Thursday

[James Thiele]

Seattle Python Interest Group meeting 7 PM Thursday 14 June 2007.

See http://www,seapig.org for location and directions.

-- 
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Third-party libs in version control

[Marcus]

Good evening,

I'm new to developing large subversion-controlled projects. This one
will involve a few third-party libraries like wxWidgets, and perhaps
Twisted. Ordinarily you could just install these into your system and
they'll end up globally (in Python's Lib/site-packages directory). Is it
proper practice to instead install the libraries into a separate [vendor
branch] of the repository and reference that instead?

I've read about vendor branches, and I'm under the impression that
you're supposed to do that /instead/ of installing the libraries
globally into Python's subdirectories... is that correct?

Marcus
-- 
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Re: Are there any python jobs worked at home from the internet?

[Gabriel Genellina]

En Sat, 09 Jun 2007 22:53:08 -0300, boyeestudio <[EMAIL PROTECTED]>  
escribió:

> Are there any python jobs worked at home from the internet?
> I want to find a part time job.
> Please give a clue to this for me.

I know of http://www.rentacoder.com/ but I've never actually used it.

-- 
Gabriel Genellina

-- 
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Re: How to get existing frames in non-current thread?

[Gabriel Genellina]

En Sat, 09 Jun 2007 21:40:40 -0300, Fabio Zadrozny <[EMAIL PROTECTED]>  
escribió:

> Is there some way to get all the frames for any given thread? -- in a way
> that does not require a compiled extension.

For the current (calling) thread, you can use sys._getframe()
For other threads, you can use sys._current_frames()
Frames have a f_back attribute pointing to the previous one, that you can  
use to navigate them.

Quoting 
sys._current_frames: Return a dictionary mapping each thread's identifier  
to the topmost stack frame currently active in that thread at the time the  
function is called. Note that functions in the traceback module can build  
the call stack given such a frame.
This is most useful for debugging deadlock: this function does not require  
the deadlocked threads' cooperation, and such threads' call stacks are  
frozen for as long as they remain deadlocked. The frame returned for a  
non-deadlocked thread may bear no relationship to that thread's current  
activity by the time calling code examines the frame.
This function should be used for internal and specialized purposes only.  
New in version 2.5.

-- 
Gabriel Genellina

-- 
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Re: urllib2 - iteration over non-sequence

[Paul Rubin]

Erik Max Francis <[EMAIL PROTECTED]> writes:
> This is really wasteful, as there's no point in reading in the whole
> file before iterating over it.  To get the same effect as file
> iteration in later versions, use the .xreadlines method::
> 
>   for line in aFile.xreadlines():
>   ...

Ehhh, a heck of a lot of web pages don't have any newlines, so you end
up getting the whole file anyway, with that method.  Something like

   for line in iter(lambda: aFile.read(4096), ''): ...

may be best.
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Are there any python jobs worked at home from the internet?

[boyeestudio]

Hi,all buddies.
Are there any python jobs worked at home from the internet?
I want to find a part time job.
Please give a clue to this for me.
Thanks a lot!
-- 
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Re: urllib2 - iteration over non-sequence

[Erik Max Francis]

Gary Herron wrote:

> So... You must explicitly read the contents of the file-like object
> yourself, and loop through the lines you self.  However, fear not --
> it's easy.   The socket._fileobject object provides a method "readlines"
> that reads the *entire* contents of the object, and returns a list of
> lines.  And you can iterate through that list of lines.  Like this:
> 
> import urllib2 
> url = urllib2.urlopen('http://www.google.com')
> for line in url.readlines():
>   print line
> url.close()

This is really wasteful, as there's no point in reading in the whole 
file before iterating over it.  To get the same effect as file iteration 
  in later versions, use the .xreadlines method::

for line in aFile.xreadlines():
...

-- 
Erik Max Francis && [EMAIL PROTECTED] && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
   If you flee from terror, then terror continues to chase you.
-- Benjamin Netanyahu
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Re: VIM editor question

[BartlebyScrivener]

On Jun 9, 1:23 pm, "Jerry Van Brimmer" <[EMAIL PROTECTED]> wrote:
> On 6/9/07, BartlebyScrivener <[EMAIL PROTECTED]> wrote:
>
> > No! That's completely wrong.
>
> No, it's not *completely* wrong. Yes, I should have mentioned the
> bg=dark entry, but that doesn't make it *completely* wrong. you're
> just showing your preference for the moria colorscheme, which is fine,
> but don't say my suggestion is *completely* wrong.
>

Er, I was kidding. Point being, it's totally customizable.

I guess I should have included a smiley face for your literal-minded
self.

rd

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Re: pyexe "format"

[John Machin]

On Jun 10, 11:25 am, John Machin <[EMAIL PROTECTED]> wrote:
> On Jun 10, 10:38 am, hg <[EMAIL PROTECTED]> wrote:
>
> > hg wrote:
> > > Hi,
>
> > > Is there a clean way to figure out that a .exe was actually generated by
> > > pyexe ?
>
> > > hg
>
> > I should gave writtent "definite" instead of "clean"
>
> > hg
>
> Reminds me of the story about a teacher trying to correct a student
> who was using rather dialectal English:
>You have went and putten "putten" when you should of putten "put"!
> :-)
>
> You should of looken at this:
>
> http://www.py2exe.org/index.cgi/WhereAmI
>
> HTH,
> John

I presumed that you were really asking: "How can Python code tell
whether it is being run in a py2exe-generated exe, or by the Python
interpreter?".

Alternatively, "How can a human inspect an exe and determine whether
it was generated by py2exe?": (1) I don't know (2) Why do you care?

Cheers,
John

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Re: pyexe "format"

[John Machin]

On Jun 10, 10:38 am, hg <[EMAIL PROTECTED]> wrote:
> hg wrote:
> > Hi,
>
> > Is there a clean way to figure out that a .exe was actually generated by
> > pyexe ?
>
> > hg
>
> I should gave writtent "definite" instead of "clean"
>
> hg

Reminds me of the story about a teacher trying to correct a student
who was using rather dialectal English:
   You have went and putten "putten" when you should of putten "put"!
:-)

You should of looken at this:

http://www.py2exe.org/index.cgi/WhereAmI

HTH,
John

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RE: Hooking exceptions outside of call stack

[Warren Stringer]

Josiah Carlson wrote:
>  >>> foo = type(foo)(foo.func_code, d, foo.func_name, foo.func_defaults,
> foo.func_closure)

Wow! I've never seen that, before. Is there documentation for `type(n)(...)`
somewhere? I did find a very useful "Decorator for Binding Constants, by
Raymond Hettinger", that uses this technique.

The calls are made from embedded classes that are constructed on the fly:

  class a(object): ...
class b(object): ...
   class c(object): ...

for `a.b[c]=1`, a.__getattr__('b') is called but 'c' need to be resolved as
an object before a.b.__getitem__(c) is called. Could a.b.__init__ set
globals so that 'c' gets resolved? Is this global namespace the same as the
`globals()` namespace? 

Cheers,

\~/

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Re: Python's "only one way to do it" philosophy isn't good?

[James Stroud]

Kay Schluehr wrote:
> On Jun 9, 12:16 pm, James Stroud <[EMAIL PROTECTED]> wrote:
>> Terry Reedy wrote:
>>> In Python, you have a choice of recursion (normal or tail)
>> Please explain this. I remember reading on this newsgroup that an
>> advantage of ruby (wrt python) is that ruby has tail recursion, implying
>> that python does not.
> 
> Proof by rumour?

"Proof" if you define "proof" by asking for clarification about a vague 
recollection of an even more vague posting. I think now I'll prove 
Fermat's Last Theorem by hailing a cab.
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How to get existing frames in non-current thread?

[Fabio Zadrozny]

Hi,

Is there some way to get all the frames for any given thread? -- in a way
that does not require a compiled extension.

Thanks,

Fabio
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Re: pyexe "format"

[hg]

hg wrote:

> Hi,
> 
> Is there a clean way to figure out that a .exe was actually generated by
> pyexe ?
> 
> hg

I should gave writtent "definite" instead of "clean"

hg

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pyexe "format"

[hg]

Hi,

Is there a clean way to figure out that a .exe was actually generated by
pyexe ?

hg


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RE: Ableton Live Python API is out!

[Warren Stringer]

Alia Khouri Write
> I have been waiting for this ages and it's finally happened! Python
> meet Live, Live meet Python!

Wow. This is very cool; thanks for the announcement!
 
> I rushed to update  http://wiki.python.org/moin/PythonInMusic but lo

Thanks for this link, as well. Very useful.  


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Re: The Concepts and Confusions of Prefix, Infix, Postfix and Fully Functional Notations

[BCB]

"Paul McGuire" <[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
> On Jun 9, 6:49 am, Lew <[EMAIL PROTECTED]> wrote:
>> > In particular, Perl code looks more like line
>> > noise than like code from any known programming language. ;))
>>
>> Hmm - I know of APL and SNOBOL.
>>
>> --
>> Lew
>
> TECO editor commands.  I don't have direct experience with TECO, but
> I've heard that a common diversion was to type random characters on
> the command line, and see what the editor would do.
>
> -- Paul
>

J

http://www.jsoftware.com/ 


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Re: Python's "only one way to do it" philosophy isn't good?

[Steven D'Aprano]

On Sat, 09 Jun 2007 22:52:32 +, Josiah Carlson wrote:

> the only thing that optimization 
> currently does in Python at present is to discard docstrings

Python, or at least CPython, does more optimizations than that. Aside from
run-time optimizations like interned strings etc., there are a small
number of compiler-time optimizations done.

Running Python with the -O (optimize) flag tells Python to ignore
assert statements. Using -OO additionally removes docstrings.

Regardless of the flag, in function (and class?) definitions like the
following:

def function(args):
"Doc string"
x = 1 
s = "this is a string constant"
"and this string is treated as a comment"
return s*x

The string-comment is ignored by the compiler just like "real" comments.
(The same doesn't necessarily hold for other data types.)


Some dead code is also optimized away:

>>> def function():
... if 0:
... print "dead code"
... return 2
...
>>> dis.dis(function)
  4   0 LOAD_CONST   1 (2)
  3 RETURN_VALUE


Lastly, in recent versions (starting with 2.5 I believe) Python includes a
peephole optimizer that implements simple constant folding: 

# Python 2.4.3
>>> dis.dis(lambda: 1+2)
  1   0 LOAD_CONST   1 (1)
  3 LOAD_CONST   2 (2)
  6 BINARY_ADD
  7 RETURN_VALUE

# Python 2.5
>>> dis.dis(lambda: 1+2)
  1   0 LOAD_CONST   2 (3)
  3 RETURN_VALUE


The above all holds for CPython. Other Pythons may implement other
optimizations.



-- 
Steven.

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Ableton Live Python API is out!

[Alia Khouri]

I have been waiting for this ages and it's finally happened! Python
meet Live, Live meet Python!

There's now a wonderful (public) bridge between (arguably) the most
exciting and innovative and easy-to-use realtime software sequencer
and (arguably) the most exciting and innovative and easy-to-use
computer programming language out there. I know the love will flow
both ways (btw, they're having problems with the mac os x port, hint,
hint... )

I rushed to update  http://wiki.python.org/moin/PythonInMusic but lo
and behold someone beat me to it. I love it when that happens
especially since I kicked off the earliest version of that page back
in the day ;-)

Some important links:

Ableton Live is at http://www.ableton.com

The forum thread announcing the api is at :
http://www.ableton.com/forum/viewtopic.php?t=66118&postdays=0&postorder=asc&start=0

And last but not least the Live python SDK sits at http://www.liveapi.org/

Enjoy!

Alia K

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Re: Python's "only one way to do it" philosophy isn't good?

[Steven D'Aprano]

On Sat, 09 Jun 2007 22:42:17 +0100, Alexander Schmolck wrote:

>> As for why tail calls are not optimized out, it was decided that being able
>> to have the stack traces (with variable information, etc.) was more useful
>> than offering tail call optimization
> 
> I don't buy this. 

Do you mean you don't believe the decision was made, or you don't agree
with the decision?


> What's more important, making code not fail arbitrarily (and
> thus making approaches to certain problems feasible that otherwise
> wouldn't be) or making it a be a bit easier to debug code that will fail
> arbitrarily? Why not only do tail-call optimization in .pyo files and
> get the best of both worlds?

Are you volunteering? If you are, I'm sure your suggestion will be
welcomed gratefully.

 
>> (do what I say).
> 
> Where did you say run out of memory and fail? More importantly how do
> you say "don't run out of memory and fail"?

If we can live with a certain amount of "arbitrary failures" in simple
arithmetic, then the world won't end if tail recursion isn't optimized
away by the compiler. You can always hand-optimize it yourself.

dont_run_out_of_memory_and_fail = 10**(10**100)  # please?


-- 
Steven.

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Re: Multiple python interpreters within the same process

[Graham Dumpleton]

On Jun 10, 9:07 am, Josiah Carlson <[EMAIL PROTECTED]>
wrote:
> André wrote:
> > On Jun 9, 5:00 pm, "Marcin Kalicinski" <[EMAIL PROTECTED]> wrote:
> >> How do I use multiple Python interpreters within the same process?
>
> >> I know there's a function Py_NewInterpreter. However, how do I use 
> >> functions
> >> like Py_RunString etc. with it? They don't take any arguments that would
> >> tell on which interpreter to run the string...?
>
> >> Marcin
>
> > You may want to look at the code 
> > modulehttp://docs.python.org/lib/module-code.html
>
> That's completely unrelated.
>
> To answer Marcin's question, from what I understand, running multiple
> Python interpreters is not supported.  There are various issues with
> object sharing and refcounts, etc., and are unlikely to be fixed soon if
> ever.

I really don't know why people keep propagating this myth that you
can't run multiple Python interpreters. :-(

The Python C API has supported multiple Python interpreter instances
within a single process for a long time. If you write your C program
correctly there isn't a problem. The only real limitation is that
different Python interpreter instances can't use different versions of
a C extension module as they when loaded are shared across all Python
interpreter instances.

C extension modules can also cause other problems as well, but this
isn't the fault of Python but of the module writers. Specifically, if
a C extension module is written to only use the simplified API for GIL
locking it can only be used with the first Python interpreter instance
created. If they use the wider GIL locking API properly then there is
no problem with using it in other Python interpreter instances.
Another issue although one which you aren't likely to come across
unless you are doing really tricky stuff, is where a C extension
module was written so as to assume that once it is loaded into a
Python interpreter instance, that that interpreter will not be
destroyed. From what I have seen Pyrex generated C extension modules
possibly have this latter problem and will cause a process to crash if
a Python interpreter instance is destroyed and then a new one created
in its place.

As proof that all this stuff can work, have a look at mod_python and
mod_wsgi. Both make use of multiple Python interpreter instances in a
single process. The mod_wsgi documentation even points out the above
problems with C extension modules in latter sections of:

  http://code.google.com/p/modwsgi/wiki/ApplicationIssues

Graham

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Re: urllib2 - iteration over non-sequence

[Gary Herron]

[EMAIL PROTECTED] wrote:
> Thanks for the reply Larry but I am still having trouble.  If i
> understand you correctly, your are just suggesting that i add an http://
> in front of the address?  However when i run this:
>
>   
 import urllib2
 site = urllib2.urlopen('http://www.google.com')
 for line in site:
  print line
 
>
> I am still getting the message:
>
> TypeError: iteration over non-sequence
>   File "", line 1
> TypeError: iteration over non-sequence
>   
Newer version of Python are willing to implement an iterator that
*reads* the contents of a file object and supplies the lines to you
one-by-one in a loop.  However, you explicitly said the version of
Python you are using, and that predates generators/iterators. 

So... You must explicitly read the contents of the file-like object
yourself, and loop through the lines you self.  However, fear not --
it's easy.   The socket._fileobject object provides a method "readlines"
that reads the *entire* contents of the object, and returns a list of
lines.  And you can iterate through that list of lines.  Like this:

import urllib2 
url = urllib2.urlopen('http://www.google.com')
for line in url.readlines():
  print line
url.close()


Gary Herron

 




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Re: Multiple python interpreters within the same process

[Josiah Carlson]

André wrote:
> On Jun 9, 5:00 pm, "Marcin Kalicinski" <[EMAIL PROTECTED]> wrote:
>> How do I use multiple Python interpreters within the same process?
>>
>> I know there's a function Py_NewInterpreter. However, how do I use functions
>> like Py_RunString etc. with it? They don't take any arguments that would
>> tell on which interpreter to run the string...?
>>
>> Marcin
> 
> You may want to look at the code module 
> http://docs.python.org/lib/module-code.html

That's completely unrelated.

To answer Marcin's question, from what I understand, running multiple 
Python interpreters is not supported.  There are various issues with 
object sharing and refcounts, etc., and are unlikely to be fixed soon if 
ever.

  - Josiah
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Re: Hooking exceptions outside of call stack

[Josiah Carlson]

Warren Stringer wrote:
> Am still trying to hook a NameError exception and continue to run. After a
> few more hours of searching the web and pouring over Martelli's book, the
> closest I've come is:
[snip]
> Is there a way of intervening as `exec cmd in globals, locals` attempts to
> translate 'c' into an object? I thought that trapping a NameError might
> work. But now, I'm not so sure.

You can always muck around with the function's globals (if the operation 
is happening inside some function...)

 >>> def foo():
... print a
...
 >>> d = {'a':1}
 >>>
 >>> foo = type(foo)(foo.func_code, d, foo.func_name, foo.func_defaults,
foo.func_closure)
 >>> a
Traceback (most recent call last):
   File "", line 1, in ?
NameError: name 'a' is not defined
 >>> foo()
1
 >>>

With a little work, you can 'merge' your namespace-like object with the 
module globals that normally exist for a function.

However, I would say again, you shouldn't be doing this kind of thing in 
production code.

  - Josiah
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Re: interating over single element array

[Basilisk96]

Thank you both for clearing that up.
-Basilisk96

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Re: Python for embedded systems with memory constraints

[MRAB]

On Jun 9, 1:33 pm, vishnu <[EMAIL PROTECTED]> wrote:
> Hi,
> Thanks Cameron for your suggestions.
> In fact I am using custom memory sub-allocator where I preallocate a
> pool of memory during initialization of my application and ensure that
> Python doesn't make any system mallocs later . With this arrangement,
> python seems to run out of preallocated memory (of 10MB) after running
> few simple scripts due to huge external fragmentation. My memory
> sub-allocator got a good design which uses the best-fit algorithm and
> coaelescing the adjacent blocks during each free call.
> If anybody out there used their own memory manager and ran Python
> without fragmentation , could provide some inputs on this.
>
>From what I remember, the best-fit algorithm isn't a good idea because
unless the free block was exactly the right size you'd tend to get
left with lots of small fragments. (Suppose that the best fit was a
free block only 4 bytes bigger than what you want; what can you do
with a free block of 4 bytes?)

A worst-fit algorithm would leave larger free blocks which are more
useful subsequently, but I think that the recommendation was next-fit
(ie use the first free block that's big enough, starting from where
you found the last one).

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Re: urllib2 - iteration over non-sequence

[rplobue]

Thanks for the reply Larry but I am still having trouble.  If i
understand you correctly, your are just suggesting that i add an http://
in front of the address?  However when i run this:

>>> import urllib2
>>> site = urllib2.urlopen('http://www.google.com')
>>> for line in site:
>>>  print line

I am still getting the message:

TypeError: iteration over non-sequence
  File "", line 1
TypeError: iteration over non-sequence

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Re: Python's "only one way to do it" philosophy isn't good?

[Josiah Carlson]

Alexander Schmolck wrote:
> Josiah Carlson <[EMAIL PROTECTED]> writes:
> 
>> James Stroud wrote:
>>> Terry Reedy wrote:
 In Python, you have a choice of recursion (normal or tail)
>>> Please explain this. I remember reading on this newsgroup that an advantage
>>> of ruby (wrt python) is that ruby has tail recursion, implying that python
>>> does not. Does python have fully optimized tail recursion as described in
>>> the tail recursion Wikipedia entry? Under what circumstances can one count
>>> on the python interpreter recognizing the possibility for optimized tail
>>> recursion?
>> Note that Terry said that you could do normal or tail recursion, he didn't
>> claim that either were optimized.  
> 
> Well yeah, but without the implication how do the two words "or tail" add to
> the information content of the sentence?

Normal and tail recursion are different, based upon whether or not one 
can technically considered to be done with the stack frame.

def normal(arg):
 if arg == 1:
 return 1
 return arg * normal(arg-1)

def tail(arg, default=1):
 if arg == 1:
 return arg * default
 return tail(arg-1, default*arg)


>> As for why tail calls are not optimized out, it was decided that being able
>> to have the stack traces (with variable information, etc.) was more useful
>> than offering tail call optimization
> 
> I don't buy this. What's more important, making code not fail arbitrarily (and
> thus making approaches to certain problems feasible that otherwise wouldn't
> be) or making it a be a bit easier to debug code that will fail arbitrarily?
> Why not only do tail-call optimization in .pyo files and get the best of both
> worlds?

I didn't make the decisions, I'm just reporting what was decided upon.

Personally, I have never found the lack of tail call optimization an 
issue for two reasons.  The first is because I typically write such 
programs in an iterative fashion.  And generally for recursion for which 
tail call optimization doesn't work (the vast majority of recursive 
algorithms I use), I typically write the algorithm recursively first, 
verify its correctness, then convert it into an iterative version with 
explicit stack.  I find it is good practice, and would be necessary 
regardless of whether Python did tail call optimization or not.


>> (do what I say).
> 
> Where did you say run out of memory and fail? More importantly how do you say
> "don't run out of memory and fail"?

By virtue of Python's underlying implementation, Python "does what I 
say", it doesn't "do what I mean".  While I may not have explicitly 
stated "run out of stack space", the underlying implementation *has* 
limited stack space.  You are stating that when you write a tail 
recursive program, you want Python to optimize it away by destroying the 
stack frames.  And that's fine.  There are tail-call optimization 
decorators available, and if you dig into sourceforge, there should even 
be a full patch to make such things available in a previous Python.

However, Python is not Lisp and is not partially defined by infinite 
recursion (see sys.setrecursionlimit() ).  Instead, it is limited by the 
C call stack (in CPython), and makes guarantees regarding what will 
always be available during debugging (the only thing that optimization 
currently does in Python at present is to discard docstrings).  If you 
want to change what is available for debugging (to make things like tail 
call optimization possible), you are free to write and submit a PEP.

In the mean time, you may need to do some source conversion.


  - Josiah
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Re: urllib2 - iteration over non-sequence

[Larry Bates]

[EMAIL PROTECTED] wrote:
> im trying to get urllib2 to work on my server which runs python
> 2.2.1.  When i run the following code:
> 
> 
> import urllib2
> for line in urllib2.urlopen('www.google.com'):
>   print line
> 
> 
> i will always get the error:
> Traceback (most recent call last):
>   File "", line 1, in ?
> TypeError: iteration over non-sequence
> 
> 
> Anyone have any answers?
> 

I ran your code:

>>> import urllib2
>>> urllib2.urlopen('www.google.com')
Traceback (most recent call last):
  File "", line 1, in 
  File "C:\Python25\lib\urllib2.py", line 121, in urlopen
return _opener.open(url, data)
  File "C:\Python25\lib\urllib2.py", line 366, in open
protocol = req.get_type()
  File "C:\Python25\lib\urllib2.py", line 241, in get_type
raise ValueError, "unknown url type: %s" % self.__original
ValueError: unknown url type: www.google.com

Note the traceback.

you need to call it with type in front of the url:

>>> import urllib2
>>> urllib2.urlopen('http://www.google.com')
>

Python's interactive mode is very useful for tracking down this type
of problem.

-Larry
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RE: Hooking exceptions outside of call stack

[Warren Stringer]

> Yes.  Python doesn't have restartable exceptions.  Perhaps you would like
> to take a look at CL or Smalltalk?
> 
> Jean-Paul

Hmmm, I wonder if anyone suggest to Philippe Petit, as stepped out 110
stories off the ground, that perhaps he would like to take a look at a
different tightrope? 

Oddly enough, you suggestion regarding "restartable exceptions" turn up a
solution:
http://www.chneukirchen.org/blog/archive/2005/03/restartable-exceptions.html


Oops, wrong language.

\~/

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urllib2 - iteration over non-sequence

[rplobue]

im trying to get urllib2 to work on my server which runs python
2.2.1.  When i run the following code:


import urllib2
for line in urllib2.urlopen('www.google.com'):
  print line


i will always get the error:
Traceback (most recent call last):
  File "", line 1, in ?
TypeError: iteration over non-sequence


Anyone have any answers?

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Re: Python's "only one way to do it" philosophy isn't good?

[Alexander Schmolck]

Josiah Carlson <[EMAIL PROTECTED]> writes:

> James Stroud wrote:
>> Terry Reedy wrote:
>>> In Python, you have a choice of recursion (normal or tail)
>>
>> Please explain this. I remember reading on this newsgroup that an advantage
>> of ruby (wrt python) is that ruby has tail recursion, implying that python
>> does not. Does python have fully optimized tail recursion as described in
>> the tail recursion Wikipedia entry? Under what circumstances can one count
>> on the python interpreter recognizing the possibility for optimized tail
>> recursion?
>
> Note that Terry said that you could do normal or tail recursion, he didn't
> claim that either were optimized.  

Well yeah, but without the implication how do the two words "or tail" add to
the information content of the sentence?

> As for why tail calls are not optimized out, it was decided that being able
> to have the stack traces (with variable information, etc.) was more useful
> than offering tail call optimization

I don't buy this. What's more important, making code not fail arbitrarily (and
thus making approaches to certain problems feasible that otherwise wouldn't
be) or making it a be a bit easier to debug code that will fail arbitrarily?
Why not only do tail-call optimization in .pyo files and get the best of both
worlds?

> (do what I say).

Where did you say run out of memory and fail? More importantly how do you say
"don't run out of memory and fail"?

'as
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RE: Hooking exceptions outside of call stack

[Jean-Paul Calderone]

On Sat, 9 Jun 2007 13:52:19 -0700, Warren Stringer <[EMAIL PROTECTED]> wrote:
>Am still trying to hook a NameError exception and continue to run. After a
>few more hours of searching the web and pouring over Martelli's book, the
>closest I've come is:
>
 import sys
 def new_exit(arg=0):
>... print 'new_exit called'
>... #old_exit(arg)
>...
 def hook(type, value, tb):
>... print 'hook called with', type
>... return
>...
 sys.excepthook = hook
 old_exit = sys.exit
 sys.exit = new_exit
 a[b]=1 # would like to get new_exit called
>hook called with exceptions.NameError

 def test():
>... sys.exit()
>...
 test()
>new_exit called
>
>The interactive session is different from running in the IDE (am using
>ActiveState's Visual Python) which exits just after the `a[b]=1` without
>calling hook.
>
>Am I missing something? Perhaps this is the wrong approach? I want Python to
>check a specific set of locals first, before checking globals. For instance:
>

Yes.  Python doesn't have restartable exceptions.  Perhaps you would like to
take a look at CL or Smalltalk?

Jean-Paul
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RE: Hooking exceptions outside of call stack

[Warren Stringer]

Am still trying to hook a NameError exception and continue to run. After a
few more hours of searching the web and pouring over Martelli's book, the
closest I've come is:

>>> import sys
>>> def new_exit(arg=0):
... print 'new_exit called'
... #old_exit(arg)
...
>>> def hook(type, value, tb):
... print 'hook called with', type
... return
...
>>> sys.excepthook = hook
>>> old_exit = sys.exit
>>> sys.exit = new_exit
>>> a[b]=1 # would like to get new_exit called
hook called with exceptions.NameError
>>>
>>> def test():
... sys.exit()
...
>>> test()
new_exit called

The interactive session is different from running in the IDE (am using
ActiveState's Visual Python) which exits just after the `a[b]=1` without
calling hook.  

Am I missing something? Perhaps this is the wrong approach? I want Python to
check a specific set of locals first, before checking globals. For instance:


a.b[c]  

will call: 

a.__getattr__('b')  

but an exception is thrown before: 

a.b.__getitem__(c) 

Is there a way of intervening as `exec cmd in globals, locals` attempts to
translate 'c' into an object? I thought that trapping a NameError might
work. But now, I'm not so sure.

Many thanks,

\~/

> Here is what I would like to do:
> 
> #
> a = Tr3()  # implements domain specific language
> a.b = 1# this works, Tr3 overrides __getattr__
> a.__dict__['b'] = 2# just so you know that b is local
> a[b] = 3   # I want to resolve locally, but get:
> 
> Traceback (most recent call last): ...
> exec cmd in globals, locals ...
> NameError: global name 'b' is not defined
> #
> 
> So far, I've tried capturing exceptions in __getattr__, __setitem__, and
> __setattr__, with no luck. I do NOT want to put `a[b]=3` inside a
> try...except block because I want to enable a command line `>>>a[b]=3`
> 
> Is there a way to hook a NameError exception outside of the call stack?
> Perhaps, inside Tr3.__init__ ? Is there a way of putting back unhandled
> NameError exceptions, so that they unwind the stack normally?
> 
> This is intended for production code.


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Re: Where can I suggest an enchantment for Python Zip lib?

[Larry Bates]

durumdara wrote:
> Hi Larry!
> 
>> durumdara wrote:
>> You can easily find out roughly how many bytes are in your .ZIP archive
>> by using following:
>>
>> zipbytes=Zobj.fp.tell()
>>
> 
> The main problem is not this.
> I want to write a backup software, and I want to:
> - see the progress in the processing of the actual file
> - abort the progress if I need it
> If I compress small files, I don't have problems.
> But with larger files (10-20 MB) I get problems, because the zipfile's
> method is uninterruptable.
> Only one way I have to control this: if I modify the ZipFile module.
> 
> dd
> 
> On Jun 7, 8:26 pm, Larry Bates <[EMAIL PROTECTED]> wrote:

On my 3 year old 3Ghz Pentium III it takes about 8 seconds to zip 20Mb file.
So what is the problem?  Not updating the process for 8-10 seconds
should be just fine for most applications.

-Larry
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Re: Hooking exceptions outside of call stack

[Josiah Carlson]

Warren Stringer wrote:
> Here is what I would like to do:
> 
> #
> a = Tr3()  # implements domain specific language
> a.b = 1# this works, Tr3 overrides __getattr__
> a.__dict__['b'] = 2# just so you know that b is local
> a[b] = 3   # I want to resolve locally, but get:
> 
> Traceback (most recent call last): ...
> exec cmd in globals, locals ...
> NameError: global name 'b' is not defined
> #

Note that your a[b]=3 is the same as '__ = b;a[__]=3'  You get that 
exception because b is not a bound name in the namespace you are 
currently using.  In order to get what you want, you will either need to 
use a['b'] = 3, a.b = 3, or a method that I refuse to describe to you.

> This is intended for production code.

The reason I refuse to describe to you the method that could 'solve' 
your particular problem is because it would be very difficult to 
differentiate between what you *want* to happen, and actual errors, 
which would make production code *very* difficult to get right.

As an alternative to a['b'], you could use a[Z.b], for an object Z:

 class Z:
 def __getattr__(self, a):
 return a

 Z = Z()

Which will have much less potential for destroying the maintainability 
and testability of your production code than hooking any trace function.


  - Josiah
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Re: Python's "only one way to do it" philosophy isn't good?

[Josiah Carlson]

James Stroud wrote:
> Terry Reedy wrote:
>> In Python, you have a choice of recursion (normal or tail)
> 
> Please explain this. I remember reading on this newsgroup that an 
> advantage of ruby (wrt python) is that ruby has tail recursion, implying 
> that python does not. Does python have fully optimized tail recursion as 
> described in the tail recursion Wikipedia entry? Under what 
> circumstances can one count on the python interpreter recognizing the 
> possibility for optimized tail recursion?

Note that Terry said that you could do normal or tail recursion, he 
didn't claim that either were optimized.  As for why tail calls are not 
optimized out, it was decided that being able to have the stack traces 
(with variable information, etc.) was more useful than offering tail 
call optimization (do what I say).

  - Josiah
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Re: Multiple python interpreters within the same process

[André]

On Jun 9, 5:00 pm, "Marcin Kalicinski" <[EMAIL PROTECTED]> wrote:
> How do I use multiple Python interpreters within the same process?
>
> I know there's a function Py_NewInterpreter. However, how do I use functions
> like Py_RunString etc. with it? They don't take any arguments that would
> tell on which interpreter to run the string...?
>
> Marcin

You may want to look at the code module 
http://docs.python.org/lib/module-code.html

André

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Multiple python interpreters within the same process

[Marcin Kalicinski]

How do I use multiple Python interpreters within the same process?

I know there's a function Py_NewInterpreter. However, how do I use functions 
like Py_RunString etc. with it? They don't take any arguments that would 
tell on which interpreter to run the string...?

Marcin


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Re: running python scripts via crontab

[davelist]

On Jun 9, 2007, at 9:10 AM, Mr SZ wrote:

> Hello all,
> I wrote a simple python script to send mail via smtp to my gmail  
> acc.I can run it as python /home/phil/Desktop/smtp.py but when I  
> add the same to my crontab as
>
> * * * * * /usr/bin/python2.5 /home/phil/Desktop/smtp.py
>
> ,it doesn't run.I checked the process by using top command and  
> python did start a thread but died soon.
>
> I need some help here.
>
> The python script uses tls-lite lib to use tls over smtp.
>

One possible issue is that I believe the crontab entries to not run  
with the same environment that your normal user login does.

If you set any environment variables in your .bashrc or .bash_profile  
file, try including those lines at the top of your crontab file.

Here's the first line in my crontab file (this is on OS X, but the  
issue is likely the same on Linux).

PATH=/opt/local/bin:/sw/bin:/sw/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/ 
usr/X11R6/bin:/Users/dreed/bin

And are you really wanting to run the script every single minute (or  
is that just for testing)?

Dave



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Re: The Concepts and Confusions of Prefix, Infix, Postfix and Fully Functional Notations

[Paul McGuire]

On Jun 9, 6:49 am, Lew <[EMAIL PROTECTED]> wrote:
> > In particular, Perl code looks more like line
> > noise than like code from any known programming language. ;))
>
> Hmm - I know of APL and SNOBOL.
>
> --
> Lew

TECO editor commands.  I don't have direct experience with TECO, but
I've heard that a common diversion was to type random characters on
the command line, and see what the editor would do.

-- Paul

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Re: Where can I suggest an enchantment for Python Zip lib?

[Paul McGuire]

Hogwarts.

Sorry, I couldn't resist either.

I'm sure you meant to say "enhancement" - an "enchantment" is a magic
spell, often used to lull an unsuspecting victim into some sort of
compliance or trance.  Actually, if you have an *enchantment* for
Python, I'm sure several people on this list would be interested. :)

But yes, *enhancement* requests can be posted on the SF feature
request list.  You may need to more clearly define what kind of data
these zlib callbacks would receive, and under what conditions they
would be called.

-- Paul

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Re: VIM editor question

[Jerry Van Brimmer]

On 6/9/07, BartlebyScrivener <[EMAIL PROTECTED]> wrote:
> On Jun 9, 1:14 am, "Jerry VanBrimmer" <[EMAIL PROTECTED]> wrote:
>
> > In your vim configuration file enter:
> >
> > colorscheme 
> >
> > Example:
> >
> > colorscheme elflord
> >
> > Restart  vim.
>
> No! That's completely wrong.

No, it's not *completely* wrong. Yes, I should have mentioned the
bg=dark entry, but that doesn't make it *completely* wrong. you're
just showing your preference for the moria colorscheme, which is fine,
but don't say my suggestion is *completely* wrong.

Cheers & Good Day.
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Re: Python's "only one way to do it" philosophy isn't good?

[John Nagle]

Bjoern Schliessmann wrote:
> Gabriel Genellina wrote:
> 
> 
>>For what I can
>>remember of my first love (Physics): if you have a small ball
>>moving inside a spherical cup, it would be almost crazy to use
>>cartesian orthogonal coordinates and Newton's laws to solve it -
>>the "obvious" way would be to use spherical coordinates and the
>>Lagrangian formulation (or at least I hope so

 Having actually solved that problem in simulation, I can report
that it's easier in Cartesian coordinates.  I used to use this as
a test of Falling Bodies, one of the first physics engines that
really worked on the hard cases.

 Spherical coordinates seem attractive until you have to deal
with friction between the ball and cup.  The ball is rotating, too,
and may be slipping with respect to the cup.  Then the simple
Physics 101 approach isn't so simple any more.

John Nagle
Animats
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Re: Gzip - gunzip using zlib

[Stefan Behnel]

flebber wrote:
> Hi Can anyone show me a working example of how to use gzip to
> decompress a file. I have read the docs at python.org and had many
> goes at it but just can't get it to work.

According to your other post, you are trying to open a ZIP archive using gzip.
Use the zipfile module instead.

Stefan
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Re: read xml file from compressed file using gzip

[Stefan Behnel]

flebber wrote:
> I was working at creating a simple program that would read the content
> of a playlist file( in this case *.k3b") and write it out . the
> compressed "*.k3b" file has two file and the one I was trying to read
> was maindata.xml

The k3b format is a ZIP archive. Use the zipfile library:

file:///usr/share/doc/python2.5-doc/html/lib/module-zipfile.html

Stefan
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Re: Repository - file scanner

[Gabriel Genellina]

En Sat, 09 Jun 2007 12:30:49 -0300, <[EMAIL PROTECTED]> escribió:

> On Jun 8, 2:33 pm, HMS Surprise <[EMAIL PROTECTED]> wrote:

>> Could someone point my muddled head at a/the python repository. I know
>> that one exists but cannot find it again. In particular I am looking
>> for a standalone search tool that given a path searches files for a
>> text string.
>
> Are you looking for
>
> A.) a Python script to search for file names that match a given text
> string?
> B.) a script to search for a given text string within a text file?
> C.) a Python repository, as in the SVN/CVS area?

D.) The Python Package Index perhaps? http://www.python.org/pypi

-- 
Gabriel Genellina

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Re: How Can I Increase the Speed of a Large Number of Date Conversions

[Terry Reedy]

"vdicarlo" <[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
| Many thanks for the lucid and helpful suggestions. Since my date range
| was only a few years, I used Some Other Guy's suggestion above, which
| the forum is saying will be deleted in five days, to make a dictionary
| of the whole range of dates when the script starts. It was so fast it
| wasn't even worth saving in a file. Made the script a LOT faster. I
| guess two thousand function calls must be faster than 200 million?
| Like maybe a hundred thousand times faster?

Any function called repeatedly with the same input is a candidate for a 
lookup table.  This is a fairly extreme example.

|| I also benefitted from studying the other suggestons. I had actually
| implemented an on the fly dictionary caching scheme for one of my
| other calculations. I don't know why it didn't occur to me to do it
| with the dates, except I think I must be assuming, as a newbie
| Pythonista, that the less I do and the more I let the libraries do the
| better off I will be.
|
| Thanks for putting me straight. As someone I know said to me when I
| told him I wanted to learn Python, "the power of Python is in the
| dictionaries".
|
| Funny how long it's taking me to learn that.

Well, look at how many of us also did not quite see the now obvious answer.

Even Python's list.sort() only fairly recently gained the optional 'key' 
parameter, which implements the decorate-sort-undecorate pattern and which 
often obsoletes the original compare-function parameter because it saves 
time by calculating (and saving) the key only once per item instead of once 
each comparison.

>>> import this
The Zen of Python, by Tim Peters
[snip]
Namespaces are one honking great idea -- let's do more of those!

I include lookup dictionaries in this admonition.

tjr



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Re: interating over single element array

[Terry Reedy]

"Basilisk96" <[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
| "Terry Reedy" <[EMAIL PROTECTED]> wrote:
| > Any what if 'filelist' is any iterable other than a string or list? 
Your
| > code is broken, and unnecessarily so.  So I would call the parameter
| > 'files' and test for isinstance(files, str) #or basestring.  And wrap 
if it
| > is.
|
| Can you give an example of such an iterable (other than a tuple)?

Tuple was the first thing I thought of, and one will break the list test. 
The next would be an iterator that walks a file hierarchy spitting out the 
names of non-directory files, or all files with a certain extension, or all 
files with a certain owner, or timestamp characteristic.

| I'd certainly like to fix my 'fix' to work for a more general case.

As I said, I think it as simple as changing 'not list' to 'is string'.

tjr




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Re: launching default browser

[alf]

Laurent Pointal wrote:

> 
> Via webbrowser module
> 
> http://docs.python.org/lib/module-webbrowser.html
> 
thx a lot. Just again Python positively surprises me.



> (note: its in top five in google search for Python + launch + browser...)

so now it will be in top four :-).
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Re: Python's "only one way to do it" philosophy isn't good?

[Terry Reedy]

"Cousin Stanley" <[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
| > In scheme, I believe you just have recursion.

I was referring to the original mimimalist core language developed by Guy 
and Sussman and as I remember it being used in the original edition of SICP 
(see Wikipedia).  I also remember statements explaining (truthfully) that 
builtin iteration is not needed because it can be defined in terms of tail 
recursion, which in Scheme is required to be optimized to be just as space 
efficient.

I see in Wikipedia that Scheme has do loops (all versions?), but I do not 
know if that was original or added.  If the former, it was de-emphasized. 
Hence my belief, even if mistaken.

| Cousin TJR 
|
|  I'm a total scheme rookie starting only about 3 days ago
|  and one of the mechanisms I went looking for was a technique
|  for iteration 
|
|  Found in the scheme docs about iteration supplied
|  via the  reduce  package 

Right.  An add-on library package, not part of the core;-)

In Python, modules can add functions (and classes, etc), but not statement 
syntax, so adding while statements defined in terms of recursion is not 
possible.

Scheme is quite elegant and worth learning at least the basics of.  My only 
point was that Sussman is an odd person to be criticizing (somewhat 
mistakingly) Python for being minimalist.

tjr



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Re: DAO and Access97 WHERE clause fails

[v.davis2]

Hello all.
Thanks for the help! John pointed out to me the flaw in my code:
Change:
   sSQL3 = 'SELECT * FROM T_Index2DirName WHERE iIndex = hsDB'
to:
   sSQL3 = 'SELECT * FROM T_Index2DirName WHERE iIndex = %ld' % hsDB
That did the trick. I had looked at the statement so often that it was 
*obviously* correct.
John also pointed me to the DAO help file that I had not been able to find.
Dennis also pointed out the correction, but went on to educate me much more 
on what I was trying to do.
BTW, I had searched extensivly on line for the answer before posting, but 
was missing the obvious, stupid coding error.
Thanks to all for getting me back on track!
--Vic


"v.davis2" <[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
> Hi all,
>
> I am attempting to use Access97 as the database to hold the results of a 
> python script. I seem to be able to make simple SELECT clauses work (like 
> SELECT * FROM TableName), but have not been able to figure out how to add 
> a WHERE clause to that (e.g., SELECT * FROM TableName WHERE myFieldName = 
> 34) This fails complaining that the wrong number of parameters are 
> present.
> I haved tried DAO36 and I have tried the ADO version with the same 
> results. Therefore I have to conclude it is my screwup!
> Help in the forum or via email would sure be appreciated! 
> ([EMAIL PROTECTED])
>
> Here is the skeleton code:
>
> import win32com.client
> daoEngine = win32com.client.Dispatch('DAO.DBEngine.35')
> sDBname = 'vpyAnalyzeDirectorySize.mdb'
> sDB = 'c:\\documents and settings\\vic\\my 
> documents\\tools\\python25\\_myscripts\\'+sDBname
> daoDB = daoEngine.OpenDatabase(sDB)
>
> sSQL1 = 'SELECT * FROM T_Index2DirName'
> daoRS = daoDB.OpenRecordset(sSQL1) # this works FINE and I can 
> play with the record set
>
> #
>
> hsDB = hash(sDB)
> sSQL3 = 'SELECT * FROM T_Index2DirName WHERE iIndex = hsDB'   # names are 
> all correct in mdb file
> daoRStest = daoDB.OpenRecordset(sSQL3) # this FAILS, even though the 
> record is there
>
> daoRS.Close()
>
>
> Traceback (most recent call last):
>  File "C:\Documents and Settings\Vic\My 
> Documents\Tools\python25\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py",
>  
> line 310, in RunScript
>exec codeObject in __main__.__dict__
>  File "C:\Documents and Settings\Vic\My 
> Documents\Tools\python25\_MyScripts\TestForPosting01.py", line 14, in 
> 
>daoRStest = daoDB.OpenRecordset(sSQL3) # this FAILS, even though 
> record is there
>  File "C:\Documents and Settings\Vic\My 
> Documents\Tools\python25\lib\site-packages\win32com\gen_py\00025E01---C000-0046x0x5x0.py",
>  
> line 523, in OpenRecordset
>, Type, Options, LockEdit)
> com_error: (-2147352567, 'Exception occurred.', (0, 'DAO.Database', 'Too 
> few parameters. Expected 1.', 'jeterr35.hlp', 5003061, -2146825227), None)
> 


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Re: piping data stream through GPG

[robert]

robert wrote:
> I played around trying to encrypt/decrypt data through GPG on the fly 
> (or worse - by using a file) (on Windows first - later to try on Linux too)
> 
> Using os.popen3 like
> 
>  >>> i,o,e=os.popen3('gpg -e -r Robert')
>  >>> # i.write('y\n')
>  >>> i.write('wefwef')
>  >>> i.close()
>  >>> # e.read(1)
>  >>> o.read(1)
> 
> hangs on o.read or e.read.
> 
> So its quite dark. Just a totally non-existing userid (-r) will result 
> significantly different like
> 
>  >>> i.write('wefwef')
> Traceback (most recent call last):
>   File "", line 1, in ?
> IOError: [Errno 22] Invalid argument
> 
> 
> GPG asks confirmation stuff (and pwd upon -d or -c) on the command line.
> How to get all this the right way?
> 
> 

I basically can handle it now by a os.popen3 cmd like
'gpg -e -r Robert --batch --always-trust',
'gpg -d -r Robert --batch --always-trust --passphrase-fd 0'

and by using a thread for feeding the child_stdin stream 
(necessary for files of significant length / more than buffers)


Robert
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Hooking exceptions outside of call stack

[Warren Stringer]

Here is what I would like to do:

#
a = Tr3()  # implements domain specific language
a.b = 1# this works, Tr3 overrides __getattr__
a.__dict__['b'] = 2# just so you know that b is local
a[b] = 3   # I want to resolve locally, but get:

Traceback (most recent call last): ...
exec cmd in globals, locals ...
NameError: global name 'b' is not defined
#

So far, I've tried capturing exceptions in __getattr__, __setitem__, and
__setattr__, with no luck. I do NOT want to put `a[b]=3` inside a
try...except block because I want to enable a command line `>>>a[b]=3` 

Is there a way to hook a NameError exception outside of the call stack?
Perhaps, inside Tr3.__init__ ? Is there a way of putting back unhandled
NameError exceptions, so that they unwind the stack normally?

This is intended for production code.

Many thanks!

Warren

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Re: Python's "only one way to do it" philosophy isn't good?

[Terry Reedy]

"James Stroud" <[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
| Terry Reedy wrote:
| > In Python, you have a choice of recursion (normal or tail)
|
| Please explain this.

I am working on a paper for Python Papers that will.  It was inspired by 
the question 'why doesn't Python do tail-recursion optimization'.

tjr



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Re: How Can I Increase the Speed of a Large Number of Date Conversions

[vdicarlo]

Many thanks for the lucid and helpful suggestions. Since my date range
was only a few years, I used Some Other Guy's suggestion above, which
the forum is saying will be deleted in five days, to make a dictionary
of the whole range of dates when the script starts. It was so fast it
wasn't even worth saving in a file. Made the script a LOT faster. I
guess two thousand function calls must be faster than 200 million?
Like maybe a hundred thousand times faster?

I also benefitted from studying the other suggestons. I had actually
implemented an on the fly dictionary caching scheme for one of my
other calculations. I don't know why it didn't occur to me to do it
with the dates, except I think I must be assuming, as a newbie
Pythonista, that the less I do and the more I let the libraries do the
better off I will be.

Thanks for putting me straight. As someone I know said to me when I
told him I wanted to learn Python, "the power of Python is in the
dictionaries".

Funny how long it's taking me to learn that.

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Re: Repository - file scanner

[kyosohma]

On Jun 8, 2:33 pm, HMS Surprise <[EMAIL PROTECTED]> wrote:
> Greetings,
>
> Could someone point my muddled head at a/the python repository. I know
> that one exists but cannot find it again. In particular I am looking
> for a standalone search tool that given a path searches files for a
> text string.
>
> Thanks,
>
> jvh

Search for text in a file, from O'Reilly's "Learning Python" book:
http://www.oreilly.com/catalog/lpython/chapter/ch09.html

Search for files given a path (or paths) and some text to search for:
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/52224
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/189973
http://www.python.org/search/hypermail/python-1994q2/0116.html

The Python repository (I think): http://svn.python.org/

Mike

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Re: Repository - file scanner

[kyosohma]

On Jun 8, 2:33 pm, HMS Surprise <[EMAIL PROTECTED]> wrote:
> Greetings,
>
> Could someone point my muddled head at a/the python repository. I know
> that one exists but cannot find it again. In particular I am looking
> for a standalone search tool that given a path searches files for a
> text string.
>
> Thanks,
>
> jvh

Are you looking for

A.) a Python script to search for file names that match a given text
string?
B.) a script to search for a given text string within a text file?
C.) a Python repository, as in the SVN/CVS area?



Here's a couple scripts for finding files given a path:

http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/52224
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/189973

And here's an interesting article on creating a Python "Find" utility:
http://www.python.org/search/hypermail/python-1994q2/0116.html

This link has a chapter from "Learning Python" by O'Reilly that talks
about looking for words within files:
http://www.oreilly.com/catalog/lpython/chapter/ch09.html

The "repository" is here: http://svn.python.org/

Enjoy!

Mike

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Re: VIM editor question

[BartlebyScrivener]

On Jun 9, 9:56 am, "Joe Riopel" <[EMAIL PROTECTED]> wrote:
> I use vim on both Windows and UNIX/Linux, and found this vimrc 
> file.http://darksmile.net/software/.vimrc.html
>
> It's pretty good and has good comments. You might want to take a look
> at that and customize it.
>
> Plus this is 
> great:http://www.usf.uni-osnabrueck.de/infoservice/doc/localhtml/vim/if_pyt...

This one also good, especially for those of us who sometimes wrap
text:

http://www.cs.cornell.edu/~djm/ubuntu/vimrc.txt

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Re: Tkinter custom drawing

[Xavier Bérard]

Thank you this is nice code. I never thought of using the move_pending
method..

Still it doesn't answer my question (which I ensure is very unclear).
But do not worry, I found some way to get throught my dilemma and I
can live easily with it. Thanks for your help.

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Re: VIM editor question

[Joe Riopel]

I use vim on both Windows and UNIX/Linux, and found this vimrc file.
http://darksmile.net/software/.vimrc.html

It's pretty good and has good comments. You might want to take a look
at that and customize it.

Plus this is great:
http://www.usf.uni-osnabrueck.de/infoservice/doc/localhtml/vim/if_python.html
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Tackling setup.py - A bug??

[Alexander Petrov]

Hi,

I've successfully compiled p4python with modified setup.py
the key to success was to split extra_compile_args's argument '-arch'
into 2 args.

below is fixed part:

[code]
 ext_modules=[Extension("P4Client", [ "P4Clientmodule.cc"
],
include_dirs=[ os.path.join( p4_api_dir,
"include", "p4" ) ],
library_dirs=[ os.path.join( p4_api_dir,
"lib" ) ],
libraries=["client", "rpc", "supp"],#
P4API libs
extra_compile_args=["-DCASE_INSENSITIVE",
"-fpascal-strings",
"-isysroot",
"/Developer/SDKs/MacOSX10.4u.sdk",
"-DOS_MACOSX",
"-DOS_MACOSX104"
, "-arch", "ppc"
,"-D%s" % p4_api_ver],
extra_link_args=[
"-Wl,-syslibroot,/Developer/SDKs/MacOSX10.4u.sdk"
  , "-arch", "ppc"
, "-framework", "System"
, "-framework", "CoreFoundation"
, "-framework", "Carbon"
],
)]
[/code]

hope it will help


--- Original Message: ---
And this followed by an setup.py install seemed to work just fine.  Ok
so now I need to backport these options into setup.py.  Here is what I
came up with..

elif os.name == "posix":
setup(name=NAME,
 version=VERSION,
 description=DESCRIPTION,
 author=AUTHOR,
 author_email=AUTHOR_EMAIL,
 maintainer=MAINTAINER,
 maintainer_email=MAINTAINER_EMAIL,
 license=LICENSE,
 url=URL,
 keywords=KEYWORDS,
 classifiers = filter(None, classifiers.split("\n")),
 long_description = "\n".join(doclines[2:]),
 py_modules=PY_MODULES,
 ext_modules=[Extension("P4Client", ["P4Clientmodule.cc"],
include_dirs=[p4_api_dir],
library_dirs=[p4_api_dir],
libraries=["client", "rpc", "supp"],#
P4API libs
extra_compile_args=["-DCASE_INSENSITIVE",
"-fpascal-strings",
"-isysroot/Developer/
SDKs/MacOSX10.4u.sdk",
"-DOS_MACOSX", "-
DOS_MACOSX104",
"-DOS_MACOSXPPC", "-
DOS_MACOSX104PPC" ,"-D%s" % p4_api_ver],
extra_link_args=[ "-Wl,-syslibroot,/
Developer/SDKs/MacOSX10.4u.sdk", "-arch ppc", "-framework Carbon" ],
)])

But low and behold it didn't work...  In the course of debugging I
found that the compile works.  The linking appears to be a problem.
In the link stage I see the command which is being run looks very
similar to my command

g++ -bundle -undefined dynamic_lookup build/temp.macosx-10.3-ppc-2.5/
P4Clientmodule.o \
-Lp4api6.1 -lclient -lrpc -lsupp -o build/lib.macosx-10.3-ppc-2.5/
P4Client.so \
 -Wl,-syslibroot,/Developer/SDKs/MacOSX10.4u.sdk -arch ppc -framework
Carbon

Not quite the same but close enough.  HERE is where the bug shows
up
If I rerun this same EXACT command at the command line - followed by a
setup.py install it works.

Can someone with a larger python brain than mine please help me figure
this out?  It's bugging the crap out fo me...
-- 
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http://zowers.googlepages.com/mailto:[EMAIL PROTECTED]
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Re: Where can I suggest an enchantment for Python Zip lib?

[Aahz]

In article <[EMAIL PROTECTED]>,
durumdara  <[EMAIL PROTECTED]> wrote:
>
> [...]

Click your heels together three times and say, "Abracadabra!"


(Sorry, couldn't resist.)
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Re: piping data stream through GPG

[robert]

robert wrote:
> I played around trying to encrypt/decrypt data through GPG on the fly 
> (or worse - by using a file) (on Windows first - later to try on Linux too)
> 
> Using os.popen3 like
> 
>  >>> i,o,e=os.popen3('gpg -e -r Robert')
>  >>> # i.write('y\n')
>  >>> i.write('wefwef')
>  >>> i.close()
>  >>> # e.read(1)
>  >>> o.read(1)
> 
> hangs on o.read or e.read.
> 
> So its quite dark. Just a totally non-existing userid (-r) will result 
> significantly different like
> 
>  >>> i.write('wefwef')
> Traceback (most recent call last):
>   File "", line 1, in ?
> IOError: [Errno 22] Invalid argument
> 
> 
> GPG asks confirmation stuff (and pwd upon -d or -c) on the command line.
> How to get all this the right way?
> 
> 

now tryed around like

 >>> i,o,e=os.popen3('gpg  --status-fd 2 --passphrase-fd 0 -e -r 
Robert','b')
 >>> i.write('y\r')
 >>> i.write('wefwef')
 >>> i.close()
 >>> # e.read(1)
 >>> o.read(1)


still just hanging... never any output (status or honey)

Robert
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piping data stream through GPG

[robert]

I played around trying to encrypt/decrypt data through GPG on the 
fly (or worse - by using a file) (on Windows first - later to try 
on Linux too)

Using os.popen3 like

 >>> i,o,e=os.popen3('gpg -e -r Robert')
 >>> # i.write('y\n')
 >>> i.write('wefwef')
 >>> i.close()
 >>> # e.read(1)
 >>> o.read(1)

hangs on o.read or e.read.

So its quite dark. Just a totally non-existing userid (-r) will 
result significantly different like

 >>> i.write('wefwef')
Traceback (most recent call last):
   File "", line 1, in ?
IOError: [Errno 22] Invalid argument


GPG asks confirmation stuff (and pwd upon -d or -c) on the command 
line.
How to get all this the right way?


Robert



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running python scripts via crontab

[Mr SZ]

Hello all,
 I wrote a simple python script to send mail via smtp to my gmail acc.I can run 
it as python /home/phil/Desktop/smtp.py but when I add the same to my crontab as

  * * * * * /usr/bin/python2.5 /home/phil/Desktop/smtp.py

 ,it doesn't run.I checked the process by using top command and python did 
start a thread but died soon.
 
 I need some help here.
 
The python script uses tls-lite lib to use tls over smtp.


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-
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Re: interating over single element array

[Marc 'BlackJack' Rintsch]

In <[EMAIL PROTECTED]>, Basilisk96
wrote:

> "Terry Reedy" <[EMAIL PROTECTED]> wrote:
>> Any what if 'filelist' is any iterable other than a string or list?  Your
>> code is broken, and unnecessarily so.  So I would call the parameter
>> 'files' and test for isinstance(files, str) #or basestring.  And wrap if it
>> is.
> 
> Can you give an example of such an iterable (other than a tuple)? I'd
> certainly like to fix my 'fix' to work for a more general case.

def iter_filenames(filename):
lines = open(filename, 'r')
for line in lines:
yield line.rstrip()
lines.close()

filenames = iter_filenames('files.txt')

Now `filenames` is an iterable over strings representing file names but
it's not a `list`.  And it's easy to come up with iterables over strings
that produce the data themselves, for example by attaching a counter to a
basename, or extracting the names from XML files, fetching them from a
database etc.

Ciao,
Marc 'BlackJack' Rintsch
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Re: VIM editor question

[BartlebyScrivener]

On Jun 9, 1:14 am, "Jerry VanBrimmer" <[EMAIL PROTECTED]> wrote:

> In your vim configuration file enter:
>
> colorscheme 
>
> Example:
>
> colorscheme elflord
>
> Restart  vim.

No! That's completely wrong.

It should be:

colorscheme moria
set bg=dark

http://www.vim.org/scripts/script.php?script_id=1464



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Re: Python for embedded systems with memory constraints

[vishnu]

Hi,
Thanks Cameron for your suggestions.
In fact I am using custom memory sub-allocator where I preallocate a
pool of memory during initialization of my application and ensure that
Python doesn't make any system mallocs later . With this arrangement,
python seems to run out of preallocated memory (of 10MB) after running
few simple scripts due to huge external fragmentation. My memory
sub-allocator got a good design which uses the best-fit algorithm and
coaelescing the adjacent blocks during each free call.
If anybody out there used their own memory manager and ran Python
without fragmentation , could provide some inputs on this.

Thanks in advance.

On 6/7/07, Cameron Laird <[EMAIL PROTECTED]> wrote:
> In article <[EMAIL PROTECTED]>,
> vishnu  <[EMAIL PROTECTED]> wrote:
> >Hi there,
> >
> >I am embedding python 2.5 on embedded system running on RTOS where I
> >had strict memory constraints.
> >As python is a huge malloc intensive application, I observed huge
> >memory fragmentation in my system which is leading to out of memory
> >after running few scripts.
> >So I decided to re-initialise the python with out restarting the whole 
> >python.
> >I tried to use Py_Finalise() after completion of each script , then
> >call Py_Initialise as is done in below link.
> >http://mail.python.org/pipermail/python-list/2001-November/114253.html
> >Which in every loop it causes a leak of 10K and after some iterations
> >it leaks of 200K etc. After few more runs this crashes. I read some
> >where this leak was solved in 2.5, but with 2.5 also I am having
> >problems
> >And also I found Py_Finalise does not completely cleanup the memory,
> >So how do I re-initialise my memory pool?
> >
> >Does anybody faced this problem earlier and got any solution hack to
> >run the python for a embedded system within own managed memory pool of
> >say 10MB?
> >
> >Any help/ideas are greatly appreciated!. Thanks in advance.
>
> Your report is interesting and important--and surprising!  I thought
> Python memory allocation is "cleaner" than you seem to be observing.
>
> I hope one of the core Python maintainers can address this.  I haven't
> worked at this level recently enough to speculate on why it's happen-
> ing, nor will I soon be in a position to volunteer to research it on
> my own (although I'd eagerly contract to do so on a modestly paid
> basis).
>
> Depending on your schedule and technology, there are lots of technical
> fixes that might apply:
> A.  quick-starting Python variations that encourage you
> to manage memory on a whole-process level;
> B.  use of one of the many Python variants (even PyPy?)
> that might give you a more favorable memory profile;
> C.  switch to Lua or Tcl as more easily embeddable
> alternative languages;
> D.  custom memory allocator;
> ...
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>
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Re: interating over single element array

[Basilisk96]

"Terry Reedy" <[EMAIL PROTECTED]> wrote:
> Any what if 'filelist' is any iterable other than a string or list?  Your
> code is broken, and unnecessarily so.  So I would call the parameter
> 'files' and test for isinstance(files, str) #or basestring.  And wrap if it
> is.

Can you give an example of such an iterable (other than a tuple)? I'd
certainly like to fix my 'fix' to work for a more general case.

Regards,
-Basilisk96

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Re: how to convert a bitmap file to an array ?

[Steve Holden]

stef wrote:
> Stefan Sonnenberg-Carstens wrote:
>> stef schrieb:
>>> hello
>>>
>>> I can find all kind of procedures to convert an array to a bitmap
>>> (wxPython, PIL),
>>> but I can't find the reverse,
>>> either
>>>- convert a bitmap to an array
>>> or
>>>   - read a bitmap file to an array
>>>
>>> thanks,
>>> Stef Mientki
>>>   
>> Take a look at the "struct" module.
>> There you fill find pack/unpack, which can do what you need.
> thanks Stefan,
> 
> but using struct, I need to know how a bitmap file is build,
> I don't know that (and I rather don't want to know that ;-)
> 
> Any better solutions (I'm a spoiled Delphi user ;-)
> 
I can offer the code below, but I can't guarantee you won't need to play 
with it. You can almost certainly ignire the fonty bits!

def _setupContext(memory, font=None, color=None):
 if font:
 memory.SetFont(font)
 else:
 memory.SetFont(wx.NullFont)
 if color:
 memory.SetTextForeground(wx.Colour(*color))

def write( text, bitmap, pos=(0,0), font=None, color=None):
 """Simple write into a bitmap doesn't do any checking."""
 memory = wx.MemoryDC()
 _setupContext(memory, font, color)
 memory.SelectObject(bitmap)
 width, height = memory.GetTextExtent(text)
 try:
 memory.DrawText(text, pos[0],pos[1],)
 finally:
 memory.SelectObject(wx.NullBitmap)
 return width

def bitmapToPil(bitmap):
 return imageToPil(bitmapToImage(bitmap))

def bitmapToImage(bitmap):
 return wx.ImageFromBitmap(bitmap)


def pilToBitmap(pil):
 return imageToBitmap(pilToImage(pil))

def pilToImage(pil):
 image = wx.EmptyImage(pil.size[0], pil.size[1])
 image.SetData(pil.convert('RGB').tostring())
 return image

def imageToPil(image):
 pil = Image.new('RGB', (image.GetWidth(), image.GetHeight()))
 pil.fromstring(image.GetData())
 return pil

def imageToBitmap(image):
 return image.ConvertToBitmap()


regards
  Steve
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Skype: holdenweb  http://del.icio.us/steve.holden
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Re: The Concepts and Confusions of Prefix, Infix, Postfix and Fully Functional Notations

[Lew]

Twisted wrote:
> On Jun 8, 7:30 pm, "Jürgen Exner" <[EMAIL PROTECTED]> wrote:
>> [EMAIL PROTECTED] wrote:
>>
>> [nothing relevant to Perl]
> 
> Perl?? Perl is even less relevant to Java than the original post,
> which admittedly has some connection to pretty much all programming
> languages. (Perl, on the other hand, has no connection to any known
> programming language. ;) In particular, Perl code looks more like line
> noise than like code from any known programming language. ;))

Hmm - I know of APL and SNOBOL.

-- 
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Re: Python's "only one way to do it" philosophy isn't good?

[Kay Schluehr]

On Jun 9, 12:16 pm, James Stroud <[EMAIL PROTECTED]> wrote:
> Terry Reedy wrote:
> > In Python, you have a choice of recursion (normal or tail)
>
> Please explain this. I remember reading on this newsgroup that an
> advantage of ruby (wrt python) is that ruby has tail recursion, implying
> that python does not.

Proof by rumour? You can use first class continuations in Ruby to
eliminate tail calls in and define higher order function wrappers
( like Python decorators ). But I wouldn't call this "fully
optimized".

> Does python have fully optimized tail recursion as
> described in the tail recursion Wikipedia entry?

No.

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Re: Working with fixed format text db's

[Lloyd Zusman]

Frank Millman <[EMAIL PROTECTED]> writes:

> On Jun 8, 5:50 pm, Neil Cerutti <[EMAIL PROTECTED]> wrote:
>> Many of the file formats I have to work with are so-called
>> fixed-format records, where every line in the file is a record,
>> and every field in a record takes up a specific amount of space.
>>
>> [ ... ]
>
> We already have '%-12s' to space fill for a length of 12, but it is
> not truly fixed-length, as if the value has a length greater than 12
> you need it to be truncated, and this construction will not do that.

In this case, we can use '%-12.12s'.

-- 
 Lloyd Zusman
 [EMAIL PROTECTED]
 God bless you.

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Re: Python's "only one way to do it" philosophy isn't good?

[Bjoern Schliessmann]

Gabriel Genellina wrote:

> For what I can
> remember of my first love (Physics): if you have a small ball
> moving inside a spherical cup, it would be almost crazy to use
> cartesian orthogonal coordinates and Newton's laws to solve it -
> the "obvious" way would be to use spherical coordinates and the
> Lagrangian formulation (or at least I hope so

Yep, that's right.

> - surely knowledgeable people will find more "obviously" which is
> the right way).

No, this case is IMHO almost classical. Movement with planar
constraints can be solved quite easy using Lagrange.

> All classical mechanics formulations may be equivalent, but 
> in certain cases one is much more suited that the others.

Or: Lagrange is the only obvious way to describe movement with
constraints.

Regards,


Björn

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Re: Python's "only one way to do it" philosophy isn't good?

[Cousin Stanley]

> 
> In scheme, I believe you just have recursion. 
> 

Cousin TJR 

  I'm a total scheme rookie starting only about 3 days ago
  and one of the mechanisms I went looking for was a technique
  for iteration  

  Found in the scheme docs about iteration supplied
  via the  reduce  package 

"Iterate and reduce are extensions of named-let 
 for writing loops that walk down one or more sequences
 such as the elements of a list or vector, the characters
 read from a port, or arithmetic series  "

  The following scheme session illustrates a trivial example 

  > , open reduce
  >
  > ( define ( list_loop this_list )
( iterate loop
( ( list* this_item this_list ) )   ; iterate expression
( ( new_list '( ) ) )   ; state   expression
  ( loop ( cons ( * 2 this_item ) new_list ) )  ; bodyexpression
  ( reverse new_list ) ) )  ; final   expression
  ; no values returned
  > 
  > ( define L '( 1 2 3 4 5 ) )
  ; no values returned
  >
  ( define result_i ( list_loop L ) )
  ; no values returned
  >
  > result_i
  '(2 4 6 8 10)
  >

  However, just as in Python the  map  function
  might be both easier to code and more readable
  in many cases 

  > ( define ( x2 n ) ( * 2 n ) )
  ; no values returned
  >
  > ( define result_m ( map x2 L ) )
  ; no values returned
  >
  > result_m
  '(2 4 6 8 10)

  Note  

No  lambdas  in my scheme code either  ;-)
 

-- 
Stanley C. Kitching
Human Being
Phoenix, Arizona


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Re: Python's "only one way to do it" philosophy isn't good?

[James Stroud]

Terry Reedy wrote:
> In Python, you have a choice of recursion (normal or tail)

Please explain this. I remember reading on this newsgroup that an 
advantage of ruby (wrt python) is that ruby has tail recursion, implying 
that python does not. Does python have fully optimized tail recursion as 
described in the tail recursion Wikipedia entry? Under what 
circumstances can one count on the python interpreter recognizing the 
possibility for optimized tail recursion?

James


=

Disclaimer: Mention of more than one programming language in post does 
not imply author's desire to begin language v. language holy battle. The 
author does not program in [some or all of the other languages mentioned 
aside from the language topical to the newsgroup] and has no opinions on 
the merits or shortcomings of said language or languages.

=
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Re: python-ldap for Python 2.5 on Windows?

[Michael Ströder]

Waldemar Osuch wrote:
> On Jun 8, 6:36 am, Benedict Verheyen <[EMAIL PROTECTED]>
> wrote:
>> Hi,
>>
>> i found python-ldap for version Python 2.4.
>> Is there i place i can find a version for 2.5?
>>
>> If not, how can i build it myself for Windows?
>>
> 
> I have managed to build it for myself using MinGW:
> http://www.osuch.org-a.googlepages.com/python-ldap-2.3.win32-py2.5.exe

I'd appreciate if someone would provide Win32 builds of python-ldap on a
regular basis. Or at least a description what to do. I could add it to
python-ldap's web site.

Ciao, Michael.
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Ang roskilde billet

[andre lerche]

Hej

Jeg er interesseret i at købe din billet, jeg bor selv på amager, så vi kan
gøre en hurtig handel.

Mvh

André
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Re: Case-Insensitive Sorting of Multi-Dimensional Lists

[Peter Otten]

Ben Finney wrote:

> mosscliffe <[EMAIL PROTECTED]> writes:
> 
>> I have tried the following, for a one dimensional list and it works,
>> but I can not get my head around this lambda. How would this be
>> written, without the lamda ?
>>
>> mylist = ['Fred','bill','PAUL','albert']
>>
>> mylist.sort(key=lambda el: el.lower())
> 
> Here's a hint:
> 
> >>> "FoO".lower()
> 'foo'
> >>> str.lower("FoO")
> 'foo'

But be aware that you lose both the ability to override and duck-typing:

>>> print r # derived from str
Upper East Side
>>> print s # unicode
München
>>> r.lower(), str.lower(r)
('Lower East Side', 'upper east side')
>>> s.lower(), str.lower(s)
Traceback (most recent call last):
  File "", line 1, in 
TypeError: descriptor 'lower' requires a 'str' object but received a
'unicode'

Peter
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Re: Working with fixed format text db's

[John Machin]

On Jun 9, 5:48 am, Mark Carter <[EMAIL PROTECTED]> wrote:
> Neil Cerutti wrote:
> > The underlying problem, of course, is the archaic flat-file
> > format with fixed-width data fields. Even the Department of
> > Education has moved on to XML for most of it's data files,
>
> :(
>
> I'm writing a small app, and was wondering the best way to store data.
> Currently the fields are separated by spaces. I was toying with the idea
> of using sqlite, yaml or json, but I think I've settled on CSV. Dull,
> but it's easy to parse for humans and computers.

Yup, humans find that parsing stuff like the following is quite easy:

"Jack ""The Ripper"" Jones","""Eltsac Ruo"", 123 Smith St",,Paris TX
12345

Cheers,
John

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Re: Working with fixed format text db's

[Frank Millman]

On Jun 8, 5:50 pm, Neil Cerutti <[EMAIL PROTECTED]> wrote:
> Many of the file formats I have to work with are so-called
> fixed-format records, where every line in the file is a record,
> and every field in a record takes up a specific amount of space.
>
> For example, one of my older Python programs contains the
> following to create a fixed-format text record for a batch of new
> students:
>
> new = file("new.dat", "w")
> if not new:
> print "Error. Could not open file new.dat for writing."
> raw_input("Press Return To Exit.")
> sys.exit(1)
>
> for s in freshmen:
> new.write(s.ssn.ljust(9))
> new.write(s.id.ljust(10))
> new.write(s.last[:16].ljust(16))
> new.write(s.first[:11].ljust(11))
> new.write(' '.ljust(10)) # Phone Number
> new.write(' '.ljust(1254)) # Empty 'filler' space.
> new.write('2813  ')
> new.write(s.major.ljust(5))
>

I have to do this occasionally, and also find it cumbersome.

I toyed with the idea of posting a feature request for a new 'fixed
length' string formatting operator, with optional parameters for left/
right-justified and space/zero-filled.

We already have '%-12s' to space fill for a length of 12, but it is
not truly fixed-length, as if the value has a length greater than 12
you need it to be truncated, and this construction will not do that.

Assume we have a new flag '!n', which defaults to left-justified and
space-filled, but allows an optional 'r' and '0' to override the
defaults.

Then the above example could be written as

format = '%!9s%!10s%!16s%!11s%!10s%!1254s%!6s%!5s'
for s in freshmen:
new.write (format %
   (s.ssn,s.id,s.last,s.first,
' ',' ','2813',s.major))

I never felt strongly enough about it to propose it, but I thought I
would mention it.

Frank Millman

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Re: interating over single element array

[Terry Reedy]

"Basilisk96" <[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
| On Jun 8, 11:54 am, "T. Crane" <[EMAIL PROTECTED]> wrote:
| You can also do this (if tuples are okay in your case):
|
| a = 1,
|
| The comma turns 'a' into a tuple (1,) which is both iterable and has a
| length of 1.
|
| I have run into this issue before with a function that took a list of
| filenames (strings), and needed to iterate over the list to operate on
| the input files. For the case when the input would be a single file, I
| needed to turn the input string into an iterable such that the 'for'
| loop would not iterate on the filename characters (a rather
| undesirable gotcha, you understand :-) ). So I solved my problem like
| this:
|
|  def loadfiles(filelist):
|if not isinstance(filelist, list):
|  filelist = filelist,

Any what if 'filelist' is any iterable other than a string or list?  Your 
code is broken, and unnecessarily so.  So I would call the parameter 
'files' and test for isinstance(files, str) #or basestring.  And wrap if it 
is.

|for filename in filelist:
|  f = open(filename,'r')
|  #do interesting stuff with file, etc...
|
| ..and it's been working very well.
|
| Cheers,
| -Basilisk96
|
| -- 
| http://mail.python.org/mailman/listinfo/python-list
| 



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Re: Python's "only one way to do it" philosophy isn't good?

[Terry Reedy]

"WaterWalk" <[EMAIL PROTECTED]> wrote in message 
news:[EMAIL PROTECTED]
| I've just read an article "Building Robust System" by Gerald Jay
| Sussman. The article is here:
| 
http://swiss.csail.mit.edu/classes/symbolic/spring07/readings/robust-systems.pdf
|
| In it there is a footprint which says:
| "Indeed, one often hears arguments against building exibility into an
| engineered sys-
| tem. For example, in the philosophy of the computer language Python it
| is claimed:

For him to imply that Python is anti-flexibility is wrong.  Very wrong.. 
He should look in a mirror.  See below.

| \There should be one|and preferably only one|obvious way to do
| it."[25] Science does
| not usually proceed this way: In classical mechanics, for example, one
| can construct equa-
| tions of motion using Newtonian vectoral mechanics, or using a
| Lagrangian or Hamiltonian
| variational formulation.[30] In the cases where all three approaches
| are applicable they are
| equivalent, but each has its advantages in particular contexts."

And in those contexts, one would hope that the method with advantages is 
somehow the obvious way to do it.  Otherwise beginners might become like 
Buriden's ass.

So I dispute that science is as different as he claims.  And I do not see 
any real value in the statement in that I do not see it saying anything 
useful to the reader, at least not in this snippet.

| I'm not sure how reasonable this statement is and personally I like
| Python's simplicity, power and elegance. So I put it here and hope to
| see some inspiring comments.

How much has Mr. Sussman actually programmed in Python and what actual 
problems did he find with the *implementation* of the philosophy?  Without 
something concrete, the complaint is rather bogus.

But here is what I find funny (and a bit maddening):  G. J. Sussman is one 
of the inventers of the Lisp dialect Scheme, a minimalist language that for 
some things has only one way to do it, let alone one obvious way.  Scheme 
would be like physics with only one of the three ways.  After all, if they 
are equivalent, only one is needed.

For example, consider scanning the items in a collection.  In Python, you 
have a choice of recursion (normal or tail), while loops, and for 
statements.  For statements are usually the obvious way, but the other two 
are available for personal taste and for specially situations such as 
walking a tree (where one might use recursion to write the generator that 
can then be used by for loops.  In scheme, I believe you just have 
recursion.  Since iteration and recursion are equivalent, why have both?

Terry Jan Reedy



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Re: PythonS?

[Paddy]

On Jun 9, 3:51 am, Michel Claveau
<[EMAIL PROTECTED]> wrote:
> Hi!
>
> Python, Iron-Python, Jython, StackLess-Python, Monty-Python,
> Movable-Python, etc.
>
> Shouldn't add a "S" to the end of "Python"?
>
> See:http://www.jfwilliam.com/Sites/1473/Python.jpg
>
> The fact of adding a "S" could constitute a PEP.
> for classification, I propose:   PEP'S
>
> --
> @-salutations
>
> Michel Claveau

I'd vote for a more serpentine Python
:-)

- Paddy.

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