date:20140331

On Mon, Mar 31, 2014 at 5:08 PM, Mark H Harris harrismh...@gmail.com wrote:
 Unicode in python3.x is (mostly) working correctly. Congratulations to all
 who worked on it, hat is off.  The problem with unicode is that it is just a
 specification. The consortium cannot force or code anything. They control
 the scripts and make the specifications. It is left to *everyone* else to
 implement. And not everyone is taking on that task with the same gusto, if
 you follow my meaning.

Considering that Pike's native double-quoted string type stored true
Unicode (not UTF-16, not eight-bit, the full Unicode range) back in
1998, you're quite correct in saying that some take on that task with
more enthusiasm than others. Of course, that exact same fact does tell
against your other and more important point, namely that people were
unable to speak non-English to each other until very recently. Good
luck.

ChrisA
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Re: Explanation of this Python language feature? [x for x in x for x in x] (to flatten a nested list)

2014-03-31 Thread Ben Finney

Mark, you are demonstrating a habit of making sweeping pronouncements
and assertions; and then, when those statements are challenged, you
act as though you never said them.

Here's a characteristic example:

Mark H Harris harrismh...@gmail.com writes:

 On 3/30/14 10:22 AM, Steven D'Aprano wrote:
  Mark H Harris harrismh...@gmail.com writes:
  I didn't really start using unicode until about 5 years ago; python
  has only really used it since python3. right?
 
  No. Python 2.2 introduced Unicode.

 I didn't ask when it was introduced, I asked when it became useful?

That's clearly not what you asked, in the material you quoted above; and
Steven's answer to your actual false assertion is entirely appropriate.

There are many other examples in this thread, but I'm not seeking to
catalogue them; merely to show an example of what I'm observing.

I hope you can see that this behaviour quickly leads many people to
quite reasonably disregard your assertions in general, and even to
ignore you altogether. Do you think you can tone down the rhetoric and
perhaps stand by the statements you actually make?

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  `\ —Henry L. Mencken |
_o__)  |
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Re: Explanation of this Python language feature? [x for x in x for x in x] (to flatten a nested list)

2014-03-31 Thread Rustom Mody

On Monday, March 31, 2014 12:23:55 PM UTC+5:30, Ben Finney wrote:
 Mark, you are demonstrating a habit of making sweeping pronouncements
 and assertions; and then, when those statements are challenged, you
 act as though you never said them.

 Here's a characteristic example:

 Mark H Harris writes:

  On 3/30/14 10:22 AM, Steven D'Aprano wrote:
   Mark H Harris  writes:
   I didn't really start using unicode until about 5 years ago; python
   has only really used it since python3. right?
   No. Python 2.2 introduced Unicode.
  I didn't ask when it was introduced, I asked when it became useful?

 That's clearly not what you asked, in the material you quoted above; and
 Steven's answer to your actual false assertion is entirely appropriate.

 There are many other examples in this thread, but I'm not seeking to
 catalogue them; merely to show an example of what I'm observing.

 I hope you can see that this behaviour quickly leads many people to
 quite reasonably disregard your assertions in general, and even to
 ignore you altogether. Do you think you can tone down the rhetoric and
 perhaps stand by the statements you actually make?

I wonder...
Is there some Unicode-corollary to Godwin's law? Something like:

Whenever people discuss unicode long enough they start talking rubbish.

Not very surprising given that unicode is related to human languages
and human languages willy-nilly are connected to politics.

It would be neat if we could stick to the 'uni(versal)' (aka math, music etc) 
aspect of unicode more and the 'needs localization' aspect less.
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Re: checking if two things do not equal None

2014-03-31 Thread Jeremy Sanders

contact.tri...@gmail.com wrote:

 if (a, b) != (None, None):
 or
 if a != None != b:
 
 Preference? Pros? Cons? Alternatives?

I couldn't see anyone else give this, but I like

if None not in (a, b):
 pass

Jeremy


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Re: OFF TOPIC Spanish in the USA [was Re: Explanation of this Python language feature?]

2014-03-31 Thread Mark Lawrence


On 31/03/2014 05:57, Mark H Harris wrote:

On 3/30/14 5:35 AM, Steven D'Aprano wrote:


Approximately 5% of the US population either do not speak English at all,
or speak it poorly. That includes approximately half a million ASL
speakers (American Sign Language, which is not a manual representation of
English but an independent language in it's own right), the majority of
whom are unable to speak or understand spoken English.


Steven, you have trolled us over to the left edge of outer left field
all the way back at the fence, dude, seriously--- and then you dropped
the ball. Geeeze... error.



Is it safe to assume that's a reference from a sport that essentially 
only gets played in the USA so you have a World Series?


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what you can do for our language.


Mark Lawrence

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Re: Explanation of this Python language feature? [x for x in x for x in x] (to flatten a nested list)

2014-03-31 Thread wxjmfauth

Unicode...

Interesting reading.

jmf
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Re: OFF TOPIC Spanish in the USA

2014-03-31 Thread Marko Rauhamaa

Mark H Harris harrismh...@gmail.com:

 The main point of the link is the status on English as an official
 language. 28 out of 50 states have legislated English as the official
 language; meaning, that you either speak and write English, or you're
 going to have a really tough time participating in culture, business,
 government, and recreation.

What does official language mean?

Finland has two official languages: Finnish and Swedish. It means you
are guaranteed to get state services in both languages. At municipal
level, you might get guarantees in one or both of the languages
depending on census data.

In California, OTOH, it's the other way around: English being official
means you are guaranteed *not* to get services in languages other than
English. If a government social worker speaks Spanish and the customer
only knows Spanish, the social worker is not legally allowed to use
Spanish to conduct their business. In Finland, no government worker is
disallowed from using any language they deem useful in their work.


Marko
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Re: Examples of modern GUI python programms

2014-03-31 Thread Sturla Molden

Metallicow metaliobovi...@gmail.com wrote:

 My opinion would be wxPython if not actually using for a mobile, or
 PySide if you are. Both of these have acceptable licenses if you want to
 go commercial also without having to pay for commercial library usage.


If you are to distribute a program using LGPL software on AppStore or
Gopgle Play, then remember that the user must be allowed to relink the
program with anpther version of the library. That is an LGPL requirement. I
don't see how this requirement can be satisfied in this case. Thus, LGPL on
AppStore or Google Play is probably put of the question. At least on iOS,
the user cannot change what you put in an App bundle. This excludes
wxPython and PySide. Thus, the only viable cross-platform choices are
commercial PyQt + commercial Qt or tkinter. In case of iOS, PyObjC is also
an option. py2app will also be useful for creating App bundles on iOS.

Sturla

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Re: Examples of modern GUI python programms

2014-03-31 Thread Metallicow

On Monday, March 31, 2014 3:48:33 AM UTC-5, Sturla Molden wrote:
 If you are to distribute a program using LGPL software on AppStore or
 Gopgle Play, then remember that the user must be allowed to relink the
 program with anpther version of the library. That is an LGPL requirement. I
 don't see how this requirement can be satisfied in this case. Thus, LGPL on
 AppStore or Google Play is probably put of the question. At least on iOS,
 the user cannot change what you put in an App bundle. This excludes
 wxPython and PySide. Thus, the only viable cross-platform choices are
 commercial PyQt + commercial Qt or tkinter. In case of iOS, PyObjC is also
 an option. py2app will also be useful for creating App bundles on iOS.
 
 Sturla

The OP didn't exactly detail what exactly was being looked for just
python on windows basically. So that part still hasn't been answered...
As far as wxPython, that is not LGPL, it is wxPython/wxWidgets which is fine 
for licensing your compiled app as however you want. 
Modifications to the library stuff for example is good in the fact with this 
that most all improvements(to the library-stuff) eventually work their way back 
in or have to be released GPL v2.

One would have to tool through the PySide agreement for their specifics, but as 
I recall it is exactly the same as Qt is, which makes sense. Riverbank/PyQt is 
not Qt, they are a separate entity, just to make that clear. The reason PySide 
was made was because Riverbank didn't want to license their bindings that same 
as Qt basically.

A lot depends on what you intend to do with the app and how many hoops you 
are willing to jump through license wise.

Just because a library is LGPL doesn't mean the authors code has to be 
depending on the circumstances. That just means usually you have to be able to 
provide the library code(and your mods to it) used.
If the author doesn't care about releasing his/her own source code, then just 
about any toolkit would be at the same level of python on windows for the 
most part.

It all depends on what the target for the app is. Windows desktop?, Windows 
Phone?, MSW XBox?, etc...
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Re: unicode as valid naming symbols

2014-03-31 Thread Antoon Pardon

On 27-03-14 17:22, Ian Kelly wrote:
 On Thu, Mar 27, 2014 at 9:28 AM, Mark H Harris harrismh...@gmail.com wrote:
 Do you think that the ability to write this would be an improvement?

 import ⌺
 ⌚ = ⌺.╩░
 ⑥ = 5*⌺.⋨⋩
 ❹ = ⑥ - 1
 ♅⚕⚛ = [⌺.✱✳**⌺.❇*❹{⠪|⌚.∣} for ⠪ in ⌺.⣚]
 ⌺.˘˜¨´՛՜(♅⚕⚛)

Steven, you're killing me here; argument by analogy does not work!
 [  -- 8 -- ]
 One of the things that Python is widely known for is its readability.
 Allowing symbols such as √ to denote identifiers may be quite
 expressive and appreciable to the person writing the code. However it
 damages readability considerably, as seen in Steven's example above.
 Personally I'm not interested in having to maintain another
 programmer's code that arbitrarily uses ⌚ as a timer function, ╩ as
 intersection or ░ as a matrix constructor.

I don't find Steven's example convincing. Sure it can be used in a way
that damages readability considerably however lots of things in python
can be abused in a way that damages readability considerably.

That you are not interested in having to maintain someone's code who
would use such symbols is irrelevant. IIRC people have used the exact
same kind of argument against decorators and the if-else operator.

It seems we are all consenting adults until someone doesn't like the
idea how it might influence his job. In that case it shouldn't be
allowed.

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Python IM server

2014-03-31 Thread Wesley

Hi all,
  I want to develop a instant message server, simply has user and group entity.

Is there any better existing open-source one?
Thus I can download and have a look.

Thanks.
Wesley
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Line of best fit

2014-03-31 Thread Jamie Mitchell

I am new to python so apologies for the ignorance with this question.

How would I apply a line of best fit to a plot?

My data are netCDF4 data files and this is essentially what I have done so far:

swh1=netCDF4.Dataset('filename','r')
hs1=swh1.variables['hs']

swh2=netCDF4.Dataset('filename'.'r')
hs2=swh2.variables['hs']

plt.plot(hs1,hs2,'.')

Cheers,

Jamie
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Re: OFF TOPIC Spanish in the USA

2014-03-31 Thread Ned Batchelder


On 3/31/14 4:39 AM, Marko Rauhamaa wrote:

Mark H Harris harrismh...@gmail.com:


The main point of the link is the status on English as an official
language. 28 out of 50 states have legislated English as the official
language; meaning, that you either speak and write English, or you're
going to have a really tough time participating in culture, business,
government, and recreation.


What does official language mean?

Finland has two official languages: Finnish and Swedish. It means you
are guaranteed to get state services in both languages. At municipal
level, you might get guarantees in one or both of the languages
depending on census data.

In California, OTOH, it's the other way around: English being official
means you are guaranteed *not* to get services in languages other than
English. If a government social worker speaks Spanish and the customer
only knows Spanish, the social worker is not legally allowed to use
Spanish to conduct their business. In Finland, no government worker is
disallowed from using any language they deem useful in their work.


Can I politely suggest that we just end this discussion?  The thread has 
been properly marked as OFF TOPIC, and it is now squarely in areas that 
are 1) politically contentious, 2) wildly subjective, 3) none of our 
areas of expertise.  No good can come from continuing.


--Ned.




Marko




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Re: Explanation of this Python language feature? [x for x in x for x in x] (to flatten a nested list)

2014-03-31 Thread Roy Smith

In article lhb0on$pcj$1...@speranza.aioe.org,
 Mark H Harris harrismh...@gmail.com wrote:

 On 3/30/14 10:22 AM, Steven D'Aprano wrote:
  In 1991, there was no wireless, no mobile computing, hardly any public
  Internet outside of the universities. It was before the Eternal
  September, and only a few years after the Great Renaming.
 
 I was using arpanet since the late 1970s.
 
  Python had just
  been released for the first time, and Windows 3.1 hadn't been (although
  3.0 had). There was no Netscape, no Mosaic graphical web browsers. Steve
  Jobs hadn't returned to Apple yet, Apple was still losing money and mind-
  share, and Google didn't even exist. It was a different era.
 
 Command line all the way babe... uuencode uudecode base64  whoohoo.

Remember when btoa/atob came out?  You got 32 bits of data in just 5 
characters.  Win!

Waiting for btou :-)

 Unicode in python3.x is (mostly) working correctly. Congratulations to 
 all who worked on it, hat is off.  The problem with unicode is that it 
 is just a specification. The consortium cannot force or code anything. 
 They control the scripts and make the specifications. It is left to 
 *everyone* else to implement.

My first introduction to unicode was a monster i18n makeover on a large 
C++ codebase.  For reasons I no longer remember, we ended up settling on 
utf-8 for native strings (with, of course, our own string class), but 
we were also using some library which was utf-16 internally (ICU4C, I 
think?).  So, we were constantly transcoding all over the place.  What a 
mess.
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Re: Line of best fit

2014-03-31 Thread Roy Smith

In article 0fb15100-15e8-46d6-a38f-b187c7012...@googlegroups.com,
 Jamie Mitchell jamiemitchell1...@gmail.com wrote:

 I am new to python so apologies for the ignorance with this question.
 
 How would I apply a line of best fit to a plot?

Python has nothing built-in which does that, but there are plenty of 
add-on modules which do those sorts of things.  One popular one is 
statsmodels (http://statsmodels.sourceforge.net/)

 plt.plot(hs1,hs2,'.')

Please tell us more about the environment you're working in.  I'm 
guessing from the fact that you're calling plt.plot(), that you've 
already got some add-on modules loaded.  Pandas, maybe?
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Re: OFF TOPIC Spanish in the USA [was Re: Explanation of this Python language feature?]

On Mon, Mar 31, 2014 at 11:41 PM, Dennis Lee Bieber
wlfr...@ix.netcom.com wrote:
 On Mon, 31 Mar 2014 16:44:56 +1100, Chris Angelico ros...@gmail.com
 declaimed the following:

official language, and pick up any government form - something fairly
important, like applying for a passport or something. How many

 Passport is a Federal form, not under State control.

Ehh, sorry, bad example then. (I'm not a Merkin, so I don't know what
you suffer under.) Pick something that is state-controlled instead.

ChrisA
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Re: Examples of modern GUI python programms

2014-03-31 Thread Jonathan Harden

On 31 Mar 2014 00:21, D. Xenakis gouzouna...@hotmail.com wrote:


... Snip ...

 What i need is to develop an android looking program (entirelly in
python) for windows, but dunno if this is possible (most propably is), and
which tool between those would help me most: tkinter - wxpython - pyqt -
pygtk .

 Any examples and suggestions are most welcome.

While I've not used it much Kivy could be useful if you want it to look
Android like, with the added benefit that you can build for android as well.
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Re: Line of best fit

2014-03-31 Thread Moritz Beber

None of these are in the standard library but why re-invent the wheel?

Using numpy:
http://docs.scipy.org/doc/numpy/reference/generated/numpy.polyfit.html

scipy:
http://docs.scipy.org/doc/scipy-0.13.0/reference/generated/scipy.stats.linregress.html

statsmodels:
http://statsmodels.sourceforge.net/devel/examples/notebooks/generated/ols.html


On Mon, Mar 31, 2014 at 1:29 PM, Jamie Mitchell jamiemitchell1...@gmail.com
 wrote:

 I am new to python so apologies for the ignorance with this question.

 How would I apply a line of best fit to a plot?

 My data are netCDF4 data files and this is essentially what I have done so
 far:

 swh1=netCDF4.Dataset('filename','r')
 hs1=swh1.variables['hs']

 swh2=netCDF4.Dataset('filename'.'r')
 hs2=swh2.variables['hs']

 plt.plot(hs1,hs2,'.')

 Cheers,

 Jamie
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Re: Python IM server

2014-03-31 Thread Lutz Horn


Hi,

  I want to develop a instant message server, simply has user and 
group entity.


Is there any better existing open-source one?


Take a look at XMPP[0]. There are some Python libraries[1].

[0] https://en.wikipedia.org/wiki/XMPP
[1] http://xmpp.org/xmpp-software/libraries/

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Re: Explanation of this Python language feature? [x for x in x for x in x] (to flatten a nested list)

2014-03-31 Thread Grant Edwards

On 2014-03-30, Rhodri James rho...@wildebst.org.uk wrote:
 On Sun, 30 Mar 2014 11:44:13 +0100, Steven D'Aprano  

 Among fans of the British writer Terry Pratchett, the usual term is
 Merkins. Including among Merkin fans.

 Many of whom even know what a merkin is, and use the term anyway.

As much as I'd rather not be called a Merkin, one can't really get mad
at Terry Pratchett fans...

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Code style query: multiple assignments in if/elif tree

Call this a code review request, if you like. I'm wondering how you'd
go about coding something like this.

Imagine you're in a train, and the brakes don't apply instantly. The
definition, in the interests of passenger comfort, is that the first
second of brake application has an acceleration of 0.2 m/s/s, the next
second has 0.425 m/s/s, and thereafter full effect of 0.85 m/s/s. You
have a state variable that says whether the brakes have just been
applied, have already been applied for at least two seconds, or
haven't yet been applied at all. Problem: Work out how far you'll go
before the brakes reach full power, and how fast you'll be going at
that point.

Here's how I currently have the code. The variable names are a tad
long, as this was also part of me teaching my brother Python.

# Already got the brakes fully on
if mode==Brake2: distance_to_full_braking_power, speed_full_brake =
0.0, curspeed
# The brakes went on one second ago, they're nearly full
elif mode==Brake1: distance_to_full_braking_power, speed_full_brake
= curspeed - 0.2125, curspeed - 0.425
# Brakes aren't on.
else: distance_to_full_braking_power, speed_full_brake = (curspeed -
0.1) + (curspeed - 0.4125), curspeed - 0.625
# If we hit the brakes now (or already have hit them), we'll go
another d meters and be going at s m/s before reaching full braking
power.

But I don't like the layout. I could change it to a single assignment
with expression-if, but that feels awkward too. How would you lay this
out?

(Note that the else case could have any of several modes in it, so I
can't so easily use a dict.)

ChrisA
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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Marko Rauhamaa

Chris Angelico ros...@gmail.com:

 Call this a code review request, if you like. I'm wondering how you'd
 go about coding something like this.

As a simple layout question, I'd do it like this:


if mode == Brake2:
# Already got the brakes fully on
distance_to_full_braking_power = 0.0
speed_full_brake = curspeed
elif mode == Brake1:
# The brakes went on one second ago, they're nearly full
distance_to_full_braking_power = curspeed - 0.2125
speed_full_brake = curspeed - 0.425
else:
# Brakes aren't on.
distance_to_full_braking_power = (curspeed - 0.1) + (curspeed - 0.4125)
speed_full_brake = curspeed - 0.625

# If we hit the brakes now (or already have hit them), we'll go another
# d meters and be going at s m/s before reaching full braking power.



Marko
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Re: Code style query: multiple assignments in if/elif tree

On Tue, Apr 1, 2014 at 2:40 AM, Marko Rauhamaa ma...@pacujo.net wrote:
 As a simple layout question, I'd do it like this:

 
 if mode == Brake2:
 # Already got the brakes fully on
 distance_to_full_braking_power = 0.0
 speed_full_brake = curspeed
 elif mode == Brake1:
 # The brakes went on one second ago, they're nearly full
 distance_to_full_braking_power = curspeed - 0.2125
 speed_full_brake = curspeed - 0.425
 else:
 # Brakes aren't on.
 distance_to_full_braking_power = (curspeed - 0.1) + (curspeed - 0.4125)
 speed_full_brake = curspeed - 0.625

 # If we hit the brakes now (or already have hit them), we'll go another
 # d meters and be going at s m/s before reaching full braking power.
 

No particular advantage over the current version - it doesn't simplify
it any, all you've done is break it across more lines.

(The unpacking may not be ideal; as I said, this was a vehicle for
teaching oddments of Python, so I used multiple assignment partly for
the sake of using it.)

Incidentally, if you want to see the code in context, it's here:

https://github.com/Rosuav/runningtime/blob/master/runningtime.py

ChrisA
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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Rustom Mody

On Monday, March 31, 2014 9:33:54 PM UTC+5:30, Chris Angelico wrote:
 On Tue, Apr 1, 2014 at 2:40 AM, Marko Rauhamaa wrote:
  As a simple layout question, I'd do it like this:
  
  if mode == Brake2:
  # Already got the brakes fully on
  distance_to_full_braking_power = 0.0
  speed_full_brake = curspeed
  elif mode == Brake1:
  # The brakes went on one second ago, they're nearly full
  distance_to_full_braking_power = curspeed - 0.2125
  speed_full_brake = curspeed - 0.425
  else:
  # Brakes aren't on.
  distance_to_full_braking_power = (curspeed - 0.1) + (curspeed - 0.4125)
  speed_full_brake = curspeed - 0.625
  # If we hit the brakes now (or already have hit them), we'll go another
  # d meters and be going at s m/s before reaching full braking power.
  

 No particular advantage over the current version - it doesn't simplify
 it any, all you've done is break it across more lines.

Not answering your original question but the above comment

Your version was sufficiently garbled indentation-wise (it may give you sweet
pleasure to know my 'client' is GG) that I gave up on reading it.

Marko's version was clear enough that it seems to match your spec
[Ive not really verified it word for word... Just sayin']

On the whole I prefer multiple assignments.
Maybe in this case use small variable names with
separate(d) explanatory comments??
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Re: Code style query: multiple assignments in if/elif tree

On Tue, Apr 1, 2014 at 3:20 AM, Rustom Mody rustompm...@gmail.com wrote:
 On the whole I prefer multiple assignments.
 Maybe in this case use small variable names with
 separate(d) explanatory comments??

Shorter variable names would certainly be the more normal, heh. I let
my brother do that part of the typing, picking names and so on. Better
for teaching to let the victi-- err, the student have the power to
choose. :)

ChrisA
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Re: checking if two things do not equal None

2014-03-31 Thread Abe

 I couldn't see anyone else give this, but I like
 if None not in (a, b):

I did.

 I am now considering:

 if None not in (a,b):
 or
 if (a is not None) and (b is not None):

However, I decided to just turn the two parameters into one (sequence), since 
they were logically grouped anyhow.


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Re: unicode as valid naming symbols

2014-03-31 Thread Ian Kelly

On Mon, Mar 31, 2014 at 3:55 AM, Antoon Pardon
antoon.par...@rece.vub.ac.be wrote:
 On 27-03-14 17:22, Ian Kelly wrote:
 On Thu, Mar 27, 2014 at 9:28 AM, Mark H Harris harrismh...@gmail.com wrote:
 Do you think that the ability to write this would be an improvement?

 import ⌺
 ⌚ = ⌺.╩░
 ⑥ = 5*⌺.⋨⋩
 ❹ = ⑥ - 1
 ♅⚕⚛ = [⌺.✱✳**⌺.❇*❹{⠪|⌚.∣} for ⠪ in ⌺.⣚]
 ⌺.˘˜¨´՛՜(♅⚕⚛)

Steven, you're killing me here; argument by analogy does not work!
 [  -- 8 -- ]
 One of the things that Python is widely known for is its readability.
 Allowing symbols such as √ to denote identifiers may be quite
 expressive and appreciable to the person writing the code. However it
 damages readability considerably, as seen in Steven's example above.
 Personally I'm not interested in having to maintain another
 programmer's code that arbitrarily uses ⌚ as a timer function, ╩ as
 intersection or ░ as a matrix constructor.

 I don't find Steven's example convincing. Sure it can be used in a way
 that damages readability considerably however lots of things in python
 can be abused in a way that damages readability considerably.

 That you are not interested in having to maintain someone's code who
 would use such symbols is irrelevant. IIRC people have used the exact
 same kind of argument against decorators and the if-else operator.

 It seems we are all consenting adults until someone doesn't like the
 idea how it might influence his job. In that case it shouldn't be
 allowed.

That was an exaggeration on my part.  It wouldn't affect my job, as I
wouldn't expect to ever actually have to maintain anything like the
above.  My greater point though is that it damages Python's
readability for no actual gain in my view.  There is nothing useful
you can do with a name that is the U+1F4A9 character that you can't do
just as easily with alphanumeric identifiers like pile_of_poo (or
куча_фекалий if one prefers; that's auto-translated, so don't blame me
if it's a poor translation). The kinds of symbols that we're talking
about here aren't part of any writing systems, and so to incorporate
them in *names* as if they were is an abuse of Unicode.

I don't think the comparisons to decorators and the if-else operator
are apt. First, because while those may degrade readability, they do
so in a constrained way.  A decorator application is just the @ symbol
and an identifier.  The if-else is just three expressions separated by
keywords.  In the case of arbitrary Unicode identifiers, we're talking
about approximately doubling the number of different characters (out
of a continuously growing set) that could be used, many of which are
easily confused with other characters. Of course the potential for
confusion already exists, but that's no justification for aggravating
it.

Second, at least in the case of decorators, while I don't dispute that
they can harm readability, I think that in the majority of cases they
actually help it.  That's because the @ syntax placed before a
function or class clearly denotes that the construct is being
decorated by something.  The alternative to the syntax is to place an
assignment like f = decorate(f) *after* the definition, where it is
much less prominent.  That the reader then potentially has to go
figure out what the decorator does is true regardless of whether the @
syntax is used or not.  I'm unable to imagine any case where an
arbitrary Unicode identifier would actually improve readability.

Finally, in my experience the consenting adults line is usually used
in the context of program or library design.  I don't believe it's
appropriate when discussing the design of the language itself, which
should be kept as clean as possible.  The logical conclusion of that
would be Lisp-like macros where every user ends up with their own
unique and incompatible version of the language, because we're all
consenting adults here, right?
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Re: unicode as valid naming symbols

2014-03-31 Thread Tim Chase

On 2014-03-31 11:40, Ian Kelly wrote:
 There is nothing useful
 you can do with a name that is the U+1F4A9 character that you can't
 do just as easily with alphanumeric identifiers like pile_of_poo (or
 куча_фекалий if one prefers; that's auto-translated, so don't blame
 me if it's a poor translation).  The kinds of symbols that we're
 talking about here aren't part of any writing systems, and so to
 incorporate them in *names* as if they were is an abuse of Unicode.

It does get more complex though, when you could have things like

 黄金屎 = \U0001f4a9

Like you, I don't expect to ever encounter something like this in the
wild, but they are indeed symbols used in a writing system. :-)

-tkc


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Re: unicode as valid naming symbols

2014-03-31 Thread Ian Kelly

On Mon, Mar 31, 2014 at 12:02 PM, Tim Chase
python.l...@tim.thechases.com wrote:
 On 2014-03-31 11:40, Ian Kelly wrote:
 There is nothing useful
 you can do with a name that is the U+1F4A9 character that you can't
 do just as easily with alphanumeric identifiers like pile_of_poo (or
 куча_фекалий if one prefers; that's auto-translated, so don't blame
 me if it's a poor translation).  The kinds of symbols that we're
 talking about here aren't part of any writing systems, and so to
 incorporate them in *names* as if they were is an abuse of Unicode.

 It does get more complex though, when you could have things like

  黄金屎 = \U0001f4a9

 Like you, I don't expect to ever encounter something like this in the
 wild, but they are indeed symbols used in a writing system. :-)

That's already a legal identifier, though.  The constituent ideographs
are categorized as Letter, Other, not symbols.
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Re: checking if two things do not equal None

2014-03-31 Thread Moritz Emanuel Beber



On 31/03/14 19:28, Abe wrote:

I couldn't see anyone else give this, but I like
if None not in (a, b):

I did.


I am now considering:
if None not in (a,b):
or
if (a is not None) and (b is not None):

That's just

if not (a is None or b is None):

but you seem to have found your way.

However, I decided to just turn the two parameters into one (sequence), since 
they were logically grouped anyhow.




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Re: unicode as valid naming symbols

2014-03-31 Thread Antoon Pardon

Op 31-03-14 19:40, Ian Kelly schreef:
 On Mon, Mar 31, 2014 at 3:55 AM, Antoon Pardon
 antoon.par...@rece.vub.ac.be wrote:
 On 27-03-14 17:22, Ian Kelly wrote:
 On Thu, Mar 27, 2014 at 9:28 AM, Mark H Harris harrismh...@gmail.com 
 wrote:
 Do you think that the ability to write this would be an improvement?

 import ⌺
 ⌚ = ⌺.╩░
 ⑥ = 5*⌺.⋨⋩
 ❹ = ⑥ - 1
 ♅⚕⚛ = [⌺.✱✳**⌺.❇*❹{⠪|⌚.∣} for ⠪ in ⌺.⣚]
 ⌺.˘˜¨´՛՜(♅⚕⚛)

Steven, you're killing me here; argument by analogy does not work!
 [  -- 8 -- ]
 One of the things that Python is widely known for is its readability.
 Allowing symbols such as √ to denote identifiers may be quite
 expressive and appreciable to the person writing the code. However it
 damages readability considerably, as seen in Steven's example above.
 Personally I'm not interested in having to maintain another
 programmer's code that arbitrarily uses ⌚ as a timer function, ╩ as
 intersection or ░ as a matrix constructor.

 I don't find Steven's example convincing. Sure it can be used in a way
 that damages readability considerably however lots of things in python
 can be abused in a way that damages readability considerably.

 That you are not interested in having to maintain someone's code who
 would use such symbols is irrelevant. IIRC people have used the exact
 same kind of argument against decorators and the if-else operator.

 It seems we are all consenting adults until someone doesn't like the
 idea how it might influence his job. In that case it shouldn't be
 allowed.
 
 That was an exaggeration on my part.  It wouldn't affect my job, as I
 wouldn't expect to ever actually have to maintain anything like the
 above.  My greater point though is that it damages Python's
 readability for no actual gain in my view.  There is nothing useful
 you can do with a name that is the U+1F4A9 character that you can't do
 just as easily with alphanumeric identifiers like pile_of_poo (or
 куча_фекалий if one prefers; that's auto-translated, so don't blame me
 if it's a poor translation). The kinds of symbols that we're talking
 about here aren't part of any writing systems, and so to incorporate
 them in *names* as if they were is an abuse of Unicode.

Your argument doesn't has much weight. First of all it can be used
for just restricting names to the ascii range. Second of all I
think a good chosen symbolic name can be more readable than a
name in a character set you are not familiar with. A good chosen
symbol will evoke a meaning with a lot of people. A name in a
character set you are not familiar with is just gibberish to
you.

 I don't think the comparisons to decorators and the if-else operator
 are apt.

I didn't make such a comparison. I just noted the arguments against
were similar.

 First, because while those may degrade readability, they do
 so in a constrained way.  A decorator application is just the @ symbol
 and an identifier.

And if abused, can totally change the working of your function. There
is no guarantee that the function returned, has any relation with the
original function. If that can't be a night mare for readability,
I don't know what is.

 The if-else is just three expressions separated by
 keywords.

Yes but if used unrestrained in arbitrary expressions will make those
expressions hard to understand.

 In the case of arbitrary Unicode identifiers, we're talking
 about approximately doubling the number of different characters (out
 of a continuously growing set) that could be used, many of which are
 easily confused with other characters. Of course the potential for
 confusion already exists, but that's no justification for aggravating
 it.

So what if we double the number of different characters? I don't care
about the number of them, I care about how meaningful they are. And
as you say confusion is already possible. A good programmer knows
how to deal with such a possible confusion, that the number of
cases increases, doesn't need to be a problem for those that care
about this.

 Second, at least in the case of decorators, while I don't dispute that
 they can harm readability, I think that in the majority of cases they
 actually help it.

But that is not a fair comparison now, is it. What you are doing here
is comparing actual use, to a worst case doom scenario.

-- 
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Re: unicode as valid naming symbols

2014-03-31 Thread Terry Reedy


On 3/31/2014 1:40 PM, Ian Kelly wrote:


Second, at least in the case of decorators, while I don't dispute that
they can harm readability, I think that in the majority of cases they
actually help it.  That's because the @ syntax placed before a
function or class clearly denotes that the construct is being
decorated by something.  The alternative to the syntax is to place an
assignment like f = decorate(f) *after* the definition, where it is
much less prominent.


Plus, it means writing and reading the name 3 times instead  of 1. This 
is not much of an issue for 'f', but it is for names like 
'modify_x07_with_qz46pt'. Names like this occur when interfacing to 
external systems that dictate the names needed (as when interfacing 
Python to Objective-C  on Macs).


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Re: Examples of modern GUI python programms

2014-03-31 Thread Sturla Molden

Metallicow metaliobovi...@gmail.com wrote:

 One would have to tool through the PySide agreement for their specifics,
 but as I recall it is exactly the same as Qt is, which makes sense. 

According to their web page, PySide is only LGPL. Qt is LGPL or commercial.


 Just because a library is LGPL doesn't mean the authors code has to be
 depending on the circumstances. That just means usually you have to be
 able to provide the library code(and your mods to it) used.

No, that would be MPL (Mozilla Public License). Many believe LGPL implies
the same freedom as MPL. It does not.

LGPL also means you also have to give the user a means to relink the
program with a different version of the library. That is a less known
restriction of LGPL. Usually this is done by providing the LGPL library as
a DLL. But a DLL is actually not sufficient, in case a different version of
the library breaks the application binary interface (ABI). In case of ABI
breakage, LGPL means the user be given access to the program source code to
recompile and relink the program. 

Because of the closed nature of app bundles on iOS, the user cannot do
anything with an .so or .dylib file. Thus, the DLL solution to LGPL
infestation is not possible on iOS, even if it were sufficient.

MPL is basically a version og LGPL that has removed the requirement to make
relinkage possible. That is e.g. why a library like Eigen is released as
MPL instead of LGPL.


Sturla

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Re: unicode as valid naming symbols

2014-03-31 Thread Terry Reedy


On 3/31/2014 3:31 PM, Antoon Pardon wrote:

Op 31-03-14 19:40, Ian Kelly schreef:



First, because while those may degrade readability, they do
so in a constrained way.  A decorator application is just the @ symbol
and an identifier.


And if abused, can totally change the working of your function. There
is no guarantee that the function returned, has any relation with the
original function. If that can't be a night mare for readability,
I don't know what is.


This is a matter of the wrapping function, not the decorator syntax 
abbreviation.


@twist_the_function_meaning
def f: return clear_expression

is no worse in this regard than the written out form

def f: return clear_expression
f = twist_the_function_meaning(f)

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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Rhodri James

On Mon, 31 Mar 2014 17:29:54 +0100, Chris Angelico ros...@gmail.com  
wrote:


On Tue, Apr 1, 2014 at 3:20 AM, Rustom Mody rustompm...@gmail.com  
wrote:

On the whole I prefer multiple assignments.
Maybe in this case use small variable names with
separate(d) explanatory comments??


Shorter variable names would certainly be the more normal, heh. I let
my brother do that part of the typing, picking names and so on. Better
for teaching to let the victi-- err, the student have the power to
choose. :)


Not just more normal, but more readable too.  The trouble with your  
original example was that the lines were too long (even ignoring the  
trouble line-wrapping caused in your post) to take in with only a couple  
of eye movements along the line.  That makes a really quite surprising  
difference to the comprehensibility of the whole thing.



--
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Re: unicode as valid naming symbols

2014-03-31 Thread Marko Rauhamaa

Terry Reedy tjre...@udel.edu:

 @twist_the_function_meaning
 def f: return clear_expression

 is no worse in this regard than the written out form

 def f: return clear_expression
 f = twist_the_function_meaning(f)

I don't remember feeling the need for either.

I have written wrappers of all sorts, but somehow that pattern just
feels alien to me so far.


Marko
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Re: Explanation of this Python language feature? [x for x in x for x in x] (to flatten a nested list)

2014-03-31 Thread Rhodri James

On Mon, 31 Mar 2014 07:08:24 +0100, Mark H Harris harrismh...@gmail.com  
wrote:



On 3/30/14 10:22 AM, Steven D'Aprano wrote:

In 1991, there was no wireless, no mobile computing, hardly any public
Internet outside of the universities. It was before the Eternal
September, and only a few years after the Great Renaming.


   I was using arpanet since the late 1970s.


I was using JANet since the early 80s, and I'm by no means the oldest
person here.  I should stop playing that card if I were you.


 I didn't really start using unicode
until about 5 years ago; python has only really used it since python3.
right?

 No. Python 2.2 introduced Unicode.

 I didn't ask when it was introduced, I asked when it became useful?


No you didn't.  You even quoted yourself as not saying it, just in
case you weren't clear about that.

And since you're so experienced, you should recognise this sound:

*plonk*

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Re: OFF TOPIC Spanish in the USA [was Re: Explanation of this Python language feature?]

2014-03-31 Thread Rhodri James

On Mon, 31 Mar 2014 06:23:46 +0100, Mark H Harris harrismh...@gmail.com  
wrote:


The main point of the link is the status on English as an official  
language.  28 out of 50 states have legislated English as the official  
language; meaning, that you either speak and write English, or you're  
going to have a really tough time participating in culture, business,  
government, and recreation.


That few?  I'm surprised.  Presumably the other states don't have any  
contention for the status of official language?


I'm also surprised that you aren't surprised that over half the states  
feel the need to specify an official language.  One might wonder why...


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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Ned Batchelder


On 3/31/14 12:03 PM, Chris Angelico wrote:

Incidentally, if you want to see the code in context, it's here:

https://github.com/Rosuav/runningtime/blob/master/runningtime.py

ChrisA


I know you didn't ask about these aspects, but they jumped out at me: 
tabs for indentation instead of spaces, and docstring-style comments in 
places that aren't docstrings.  These seem like unusual choices.


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Re: OFF TOPIC Spanish in the USA [was Re: Explanation of this Python language feature?]

2014-03-31 Thread Terry Reedy


On 3/31/2014 4:47 PM, Rhodri James wrote:

On Mon, 31 Mar 2014 06:23:46 +0100, Mark H Harris
harrismh...@gmail.com wrote:


The main point of the link is the status on English as an official
language.  28 out of 50 states have legislated English as the official
language; meaning, that you either speak and write English, or you're
going to have a really tough time participating in culture, business,
government, and recreation.


Perhaps the link was
https://en.wikipedia.org/wiki/Languages_of_the_United_States#Official_language_status


That few?  I'm surprised.  Presumably the other states don't have any
contention for the status of official language?


The modern 'English primary' movement, with its first state success in 
1981, was a reaction to the 'Spanish co-equal' movement of the 1970s. 
Without state-by-state data on the push for legislation, I see no clear 
pattern in the list of which states have such a law.



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Re: Code style query: multiple assignments in if/elif tree

On Tue, Apr 1, 2014 at 8:42 AM, Ned Batchelder n...@nedbatchelder.com wrote:
 On 3/31/14 12:03 PM, Chris Angelico wrote:

 Incidentally, if you want to see the code in context, it's here:

 https://github.com/Rosuav/runningtime/blob/master/runningtime.py

 ChrisA


 I know you didn't ask about these aspects, but they jumped out at me: tabs
 for indentation instead of spaces, and docstring-style comments in places
 that aren't docstrings.  These seem like unusual choices.

Tabs instead of spaces? They're plenty common enough, but I am *not*
getting into that debate now. The file's perfectly consistent - aside
from inside strings, all indentation is done with tabs, one per level.

How do you go about doing multi-line comments? I know I've seen other
code using triple-quoted strings for long comments before.

ChrisA
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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Ben Finney

Chris Angelico ros...@gmail.com writes:

 How do you go about doing multi-line comments? I know I've seen other
 code using triple-quoted strings for long comments before.

Just use a sequence of one-line comments::

# Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut a
# sapien tempor, suscipit orci sed, elementum nisl. Suspendisse at
# lacus ut diam dignissim lobortis ac vitae augue.
#
# Phasellus bibendum neque a justo vulputate, quis accumsan quam
# egestas. Etiam aliquet blandit ante sit amet cursus.

A decent code editor (e.g. Emacs, Vim) will allow manipulation of
a sequence of one-line comments in Python's comment style, and allow
treating it as a paragraphs for purposes such as re-wrapping the lines.

I agree with others that triple-quoted strings are best reserved for
string literals (including docstrings), not comments.

-- 
 \ “Alternative explanations are always welcome in science, if |
  `\   they are better and explain more. Alternative explanations that |
_o__) explain nothing are not welcome.” —Victor J. Stenger, 2001-11-05 |
Ben Finney

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Re: Code style query: multiple assignments in if/elif tree

On Tue, Apr 1, 2014 at 9:57 AM, Ben Finney ben+pyt...@benfinney.id.au wrote:
 Chris Angelico ros...@gmail.com writes:

 How do you go about doing multi-line comments? I know I've seen other
 code using triple-quoted strings for long comments before.

 Just use a sequence of one-line comments::

 # Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut a
 # sapien tempor, suscipit orci sed, elementum nisl. Suspendisse at
 # lacus ut diam dignissim lobortis ac vitae augue.
 #
 # Phasellus bibendum neque a justo vulputate, quis accumsan quam
 # egestas. Etiam aliquet blandit ante sit amet cursus.

 A decent code editor (e.g. Emacs, Vim) will allow manipulation of
 a sequence of one-line comments in Python's comment style, and allow
 treating it as a paragraphs for purposes such as re-wrapping the lines.

 I agree with others that triple-quoted strings are best reserved for
 string literals (including docstrings), not comments.

Fair enough. I can't remember where (or when!) it was that I learned
triple-quoted strings were appropriately abused as comments, so I've
just done a quick re-layout into hash comments.

ChrisA
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Re: Line of best fit

2014-03-31 Thread Sturla Molden

Roy Smith r...@panix.com wrote:

 Please tell us more about the environment you're working in.  I'm 
 guessing from the fact that you're calling plt.plot(), that you've 
 already got some add-on modules loaded.  Pandas, maybe?

Probably matplotlib.pyplot

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Re: unicode as valid naming symbols

2014-03-31 Thread Ian Kelly

On Mon, Mar 31, 2014 at 1:31 PM, Antoon Pardon
antoon.par...@rece.vub.ac.be wrote:
 Op 31-03-14 19:40, Ian Kelly schreef:
 That was an exaggeration on my part.  It wouldn't affect my job, as I
 wouldn't expect to ever actually have to maintain anything like the
 above.  My greater point though is that it damages Python's
 readability for no actual gain in my view.  There is nothing useful
 you can do with a name that is the U+1F4A9 character that you can't do
 just as easily with alphanumeric identifiers like pile_of_poo (or
 куча_фекалий if one prefers; that's auto-translated, so don't blame me
 if it's a poor translation). The kinds of symbols that we're talking
 about here aren't part of any writing systems, and so to incorporate
 them in *names* as if they were is an abuse of Unicode.

 Your argument doesn't has much weight. First of all it can be used
 for just restricting names to the ascii range.

I disagree.  Non-ASCII written names are useful to anybody who prefers
not to do all their programming in English.

 Second of all I
 think a good chosen symbolic name can be more readable than a
 name in a character set you are not familiar with. A good chosen
 symbol will evoke a meaning with a lot of people. A name in a
 character set you are not familiar with is just gibberish to
 you.

Well, this is the path taken by APL.  It has its supporters.  It's not
known for being readable.

 I don't think the comparisons to decorators and the if-else operator
 are apt.

 I didn't make such a comparison. I just noted the arguments against
 were similar.

That's the comparison to which I was referring.

 First, because while those may degrade readability, they do
 so in a constrained way.  A decorator application is just the @ symbol
 and an identifier.

 And if abused, can totally change the working of your function. There
 is no guarantee that the function returned, has any relation with the
 original function. If that can't be a night mare for readability,
 I don't know what is.

As Terry Reedy noted, this has nothing to do with the decorator
syntax, so it isn't much of an argument against having such syntax.

 The if-else is just three expressions separated by
 keywords.

 Yes but if used unrestrained in arbitrary expressions will make those
 expressions hard to understand.

I don't disagree.  I hardly ever use it myself, certainly only if it
can fit comfortably into one line, which is rare.  But it's still
quite limited in syntactic scope.

 In the case of arbitrary Unicode identifiers, we're talking
 about approximately doubling the number of different characters (out
 of a continuously growing set) that could be used, many of which are
 easily confused with other characters. Of course the potential for
 confusion already exists, but that's no justification for aggravating
 it.

 So what if we double the number of different characters? I don't care
 about the number of them, I care about how meaningful they are. And
 as you say confusion is already possible. A good programmer knows
 how to deal with such a possible confusion, that the number of
 cases increases, doesn't need to be a problem for those that care
 about this.

So tell me then, how would you deal with it?  In the case of script
identifiers, it's often not hard to discern from context whether a
particular character is e.g. a Latin h or a Cyrillic һ.  Assuming the
original author wasn't being intentionally obfuscatory, if the rest of
the identifier is Cyrillic then the character is probably also
Cyrillic.  If it's a one-character identifier, then hopefully the rest
of the module is consistent and you can guess from that.  If the
identifier in question is just one symbol though, then you have a lot
less context.


 Second, at least in the case of decorators, while I don't dispute that
 they can harm readability, I think that in the majority of cases they
 actually help it.

 But that is not a fair comparison now, is it. What you are doing here
 is comparing actual use, to a worst case doom scenario.

I contend that there is no scenario with arbitrary Unicode identifiers
where readability is improved.
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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Ethan Furman

On 03/31/2014 04:12 PM, Chris Angelico wrote:

On Tue, Apr 1, 2014 at 9:57 AM, Ben Finney ben+pyt...@benfinney.id.au wrote:

Chris Angelico ros...@gmail.com writes:

How do you go about doing multi-line comments? I know I've seen other
code using triple-quoted strings for long comments before.

Just use a sequence of one-line comments::

# Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut a
# sapien tempor, suscipit orci sed, elementum nisl. Suspendisse at
# lacus ut diam dignissim lobortis ac vitae augue.
#
# Phasellus bibendum neque a justo vulputate, quis accumsan quam
# egestas. Etiam aliquet blandit ante sit amet cursus.

A decent code editor (e.g. Emacs, Vim) will allow manipulation of
a sequence of one-line comments in Python's comment style, and allow
treating it as a paragraphs for purposes such as re-wrapping the lines.

I agree with others that triple-quoted strings are best reserved for
string literals (including docstrings), not comments.

Fair enough. I can't remember where (or when!) it was that I learned
triple-quoted strings were appropriately abused as comments, so I've
just done a quick re-layout into hash comments.

Personally, I use the sequence of one-line comments.

But, hey, Guido [1] himself likes the triple-quoted string as comment feature [2], so feel free to use it yourself if
you like.

--
~Ethan~

[1] https://mail.python.org/pipermail/python-dev/2013-March/124947.html
[2] https://mail.python.org/pipermail/python-ideas/2009-October/006204.html
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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Steven D'Aprano

On Tue, 01 Apr 2014 10:12:38 +1100, Chris Angelico wrote:
[...]
 I agree with others that triple-quoted strings are best reserved for
 string literals (including docstrings), not comments.
 
 Fair enough. I can't remember where (or when!) it was that I learned
 triple-quoted strings were appropriately abused as comments, so I've
 just done a quick re-layout into hash comments.

Probably here :-)

But note the emphasis on abused. The only time I would use triple-
quoted strings as comments is if I wanted to quickly comment out a 
section of code:

do_this()
do_that()
'''
def do_something_else():
Docstring
pass
do_something_else()
'''
do_more()
do_less()


sort of thing. (Note the cunning use of ''' instead of .) But I 
wouldn't leave it like that in production code.

It's *tempting* to use  to mark out a large block of text, and I 
wouldn't say that doing so was wrong, but it's a bit different, and 
programmers are very like cats: they don't like different.


-- 
Steven D'Aprano
http://import-that.dreamwidth.org/
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Re: Line of best fit

2014-03-31 Thread Steven D'Aprano

On Mon, 31 Mar 2014 04:29:15 -0700, Jamie Mitchell wrote:

 I am new to python so apologies for the ignorance with this question.
 
 How would I apply a line of best fit to a plot?

That depends on what software you are using to generate the plot. I see 
you have this line of code:

 plt.plot(hs1,hs2,'.')

but you haven't told us what plt is, where it comes from, or anything 
needed for us to answer your question.

So, start by telling us what plt is, and we may be able to tell you 
whether or not it supports lines of best fit.




-- 
Steven D'Aprano
http://import-that.dreamwidth.org/
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Re: Python IM server

2014-03-31 Thread Wesley

在 2014年3月31日星期一UTC+8下午8时37分32秒，Lutz Horn写道：
 Hi,
 
 
 
I want to develop a instant message server, simply has user and 
 
  group entity.
 
  
 
  Is there any better existing open-source one?
 
 
 
 Take a look at XMPP[0]. There are some Python libraries[1].
 
 
 
 [0] https://en.wikipedia.org/wiki/XMPP
 
 [1] http://xmpp.org/xmpp-software/libraries/
 
 
 
 -- 
 
 Opt out of global data surveillance programs like PRISM, XKeyscore and 
 
 Tempora.
 
 https://prism-break.org

I am looking at telepathy, empathy.
Currently instant message is urgent, but needs voice/video call in the future.

For instant message, I have user-to-user and user-to-group cases. 
Don't know if it suits well.
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Re: Examples of modern GUI python programms

2014-03-31 Thread Metallicow

On Monday, March 31, 2014 3:16:16 PM UTC-5, Sturla Molden wrote:
 
 According to their web page, PySide is only LGPL. Qt is LGPL or commercial.



Licensing

PySide has been published as a response to the lack of suitably licensed Qt 
bindings for Python. PySide is licensed under the LGPL version 2.1 license, 
allowing both Free/Open source software and proprietary software development.


Read the legal definition of/and proprietary, then go consult a lawyer. That is 
caught as an exception/addition to the LGPL in the wording.
I don't think anyone pressing the issue would get very far at all, unless there 
is a real good reason your own non-library source should be disclosed. Are 
there any legal precedents yet? If you didn't pay for it, or don't have a 
class action suit, or is of national security, then good luck. 

So, yes, PySide is acceptable also in certain situations you don't have to 
disclose own source. May need to consult with Qt personally on the matter if a 
Qt license is actually needed for your particular project, but in plain legal 
wording of the LGPL/Qts/PySides agreements, no, it is not but there are a few 
rules that have been layed out you will need to follow if you don't have a Qt 
license.

Anywho, here is some infos detailing a bit more commonly asked situations on 
their forums regarding PySide.
http://qt-project.org/wiki/About-PySide
http://qt-project.org/forums/viewthread/34770

If you do have a Qt license, then the rules change a bit more in your favor at 
levels of what you can ignore, that others can't legally.
A couple of our team members has a license to cover the stuff we do, so I don't 
worry about it much. The majority of it is open anyway, but pity those who 
expect everything for free. *I can hear it now* boo hoo pdf format is finally 
free and open after all these years of adobe's money*grubbin*making. geez...
Lesson is: Any software/hardware dev should be familiar with the licensing 
terms of the toolkits they intend to use. There are always hoops to jump 
through for Free-Types. Everyone needs to eat also, because as of this 
writing Money has yet to be abolished in this needy world of ours. And also 
it seems to fuel development in certain cases also.


I often find the writings on the GPL pages about stuff related similarly to 
sound like a Richard being a crybaby at times, even tho I do respect him for 
his views he tries to emboss on everyone to create a 
not-exactly-freeier-but-just-more-open overall software society. If everyone 
had a flat wallet, then this idea would work out nicely.
If I ever write a printer driver, I will make sure I license it GPL and 
personally send him a copy to inspect, believe me. Maybe when the next 
raspberry pi revision comes out he'll send 1000's of them out for free also to 
his supporters and developers also, but I somehow doubt it.
http://www.gnu.org/philosophy/proprietary.html

Anyhow, this should hopefully be enough infos for the OP to get a general idea 
of what toolkit would be needed for whatever project is in mind. 
As I say ,If not satisfied, contact sales. They are always reassuring to sound 
the least.
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Re: unicode as valid naming symbols

I personally believe that it becomes hard to have even a programming
language overcome cultural learning styles, and programmatic differences,
because of nurture vs nature.

We can all program something which results in a similar return value, but
overcoming the nurturing the internet provides, becomes an imperative.

I'll just offer a reference to avoid personal mistakes in explaining
something that relates to how programmers/computer scientists/electrical
engineers approach their end results, and why those end results may still
differ in the mentality of the individual, or group, outcome of developing
A.I. systems:

http://en.wikipedia.org/wiki/Ethnolinguistics

http://en.wikipedia.org/wiki/Cognitive_anthropology

http://en.wikipedia.org/wiki/Cognitive_science

The latter probably explains what I mean in more depth than the two
formers.


On Mon, Mar 31, 2014 at 8:47 PM, Ian Kelly ian.g.ke...@gmail.com wrote:

 On Mon, Mar 31, 2014 at 1:31 PM, Antoon Pardon
 antoon.par...@rece.vub.ac.be wrote:
  Op 31-03-14 19:40, Ian Kelly schreef:
  That was an exaggeration on my part.  It wouldn't affect my job, as I
  wouldn't expect to ever actually have to maintain anything like the
  above.  My greater point though is that it damages Python's
  readability for no actual gain in my view.  There is nothing useful
  you can do with a name that is the U+1F4A9 character that you can't do
  just as easily with alphanumeric identifiers like pile_of_poo (or
  куча_фекалий if one prefers; that's auto-translated, so don't blame me
  if it's a poor translation). The kinds of symbols that we're talking
  about here aren't part of any writing systems, and so to incorporate
  them in *names* as if they were is an abuse of Unicode.
 
  Your argument doesn't has much weight. First of all it can be used
  for just restricting names to the ascii range.

 I disagree.  Non-ASCII written names are useful to anybody who prefers
 not to do all their programming in English.

  Second of all I
  think a good chosen symbolic name can be more readable than a
  name in a character set you are not familiar with. A good chosen
  symbol will evoke a meaning with a lot of people. A name in a
  character set you are not familiar with is just gibberish to
  you.

 Well, this is the path taken by APL.  It has its supporters.  It's not
 known for being readable.

  I don't think the comparisons to decorators and the if-else operator
  are apt.
 
  I didn't make such a comparison. I just noted the arguments against
  were similar.

 That's the comparison to which I was referring.

  First, because while those may degrade readability, they do
  so in a constrained way.  A decorator application is just the @ symbol
  and an identifier.
 
  And if abused, can totally change the working of your function. There
  is no guarantee that the function returned, has any relation with the
  original function. If that can't be a night mare for readability,
  I don't know what is.

 As Terry Reedy noted, this has nothing to do with the decorator
 syntax, so it isn't much of an argument against having such syntax.

  The if-else is just three expressions separated by
  keywords.
 
  Yes but if used unrestrained in arbitrary expressions will make those
  expressions hard to understand.

 I don't disagree.  I hardly ever use it myself, certainly only if it
 can fit comfortably into one line, which is rare.  But it's still
 quite limited in syntactic scope.

  In the case of arbitrary Unicode identifiers, we're talking
  about approximately doubling the number of different characters (out
  of a continuously growing set) that could be used, many of which are
  easily confused with other characters. Of course the potential for
  confusion already exists, but that's no justification for aggravating
  it.
 
  So what if we double the number of different characters? I don't care
  about the number of them, I care about how meaningful they are. And
  as you say confusion is already possible. A good programmer knows
  how to deal with such a possible confusion, that the number of
  cases increases, doesn't need to be a problem for those that care
  about this.

 So tell me then, how would you deal with it?  In the case of script
 identifiers, it's often not hard to discern from context whether a
 particular character is e.g. a Latin h or a Cyrillic һ.  Assuming the
 original author wasn't being intentionally obfuscatory, if the rest of
 the identifier is Cyrillic then the character is probably also
 Cyrillic.  If it's a one-character identifier, then hopefully the rest
 of the module is consistent and you can guess from that.  If the
 identifier in question is just one symbol though, then you have a lot
 less context.

 
  Second, at least in the case of decorators, while I don't dispute that
  they can harm readability, I think that in the majority of cases they
  actually help it.
 
  But that is not a fair comparison now, is it. What you are doing here
  is comparing

Re: unicode as valid naming symbols

This brings us into a juxtaposition between how cultures have tried to
hybridize their mentalities, into more of an empathic means of
communication via a formulatic set of coding, and the philosophy thereof,
and, 3D renderings of what we visualize, and how we come to the
conclusions of these philosophies of what we want to accomplish within the
technological age we live within.

Maybe not the best way I could explain it, but it has a bunch of fancy
words in it.
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Re: Examples of modern GUI python programms

Caveat emptor(I have a copy of Latin For Idiots).

When you get through with refining, in whatever language, the open
source/proprietary app you're developing, is there anyway you can say for
sure how many people's work went into things under different licenses
accompanying what you may have copy and pasted into it, and neither can the
individuals who developed the systems they designed, and threw a license
on it?

*Standing on the shoulder's of giants can still be unsteady ground.*
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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Steven D'Aprano

On Tue, 01 Apr 2014 01:33:09 +1100, Chris Angelico wrote:

 Call this a code review request, if you like. I'm wondering how you'd go
 about coding something like this.

I wouldn't. I'd start off by analysing the problem, and putting it into 
the simplest format possible, and *then* start writing code if and only 
if needed. See below.

The first mistake of computational mathematics is to do the computation 
before the mathematics, and the Holy Grail is to avoid the computation 
altogether.

 
 Imagine you're in a train, and the brakes don't apply instantly. The
 definition, in the interests of passenger comfort, 

Ah, you're using comfort in the modern sense, i.e. what people used to 
call discomfort :-P

The scenario you describe has (effectively) infinite rate-of-change-of-
acceleration, often called jerk. (A jerk is a rapid change in 
acceleration.) Human comfort is (within reasonable limits) more affected 
by jerk than acceleration. The passengers will feel three quite 
distinctive jerks, one when the brakes are first applied (which is 
probably reasonable), then one at 1s, then again at 2s. That's not 
comfortable by any stretch of the imagination.


 is that the first
 second of brake application has an acceleration of 0.2 m/s/s, the next
 second has 0.425 m/s/s, and thereafter full effect of 0.85 m/s/s. 

In mathematics, this is called  hybrid function, and is usually written 
like this:

 g(t) for t  0
f(t) = { 42 for t == 0
 h(t) for t  0

or something similar. (The opening brace { ought to be large enough to 
cover all three lines, and there is no closing brace.)

In your case, you have three constant functions.


 You
 have a state variable that says whether the brakes have just been
 applied, have already been applied for at least two seconds, or haven't
 yet been applied at all. 

I wouldn't model it that way. Especially since you've missed at least one 
state :-) I'd model the acceleration as a function of time, otherwise you 
have to convert a time into a state. Nevertheless, if you insist, we can 
use a state variable instead:

  0 for state == BRAKES NOT APPLIED YET
accel = { 0.2 for state == BRAKES ON FOR BETWEEN 0 AND 1 SECOND
  0.425 for STATE == BRAKES ON FOR BETWEEN 1 AND 2 SECOND
  0.85 for state == BRAKES ON FOR MORE THAN 2 SECONDS

Implied, but not stated, is that once the train stops, acceleration also 
goes to zero -- the train does not start moving backwards.

Haskell has nifty pattern-matching syntax for this that looks quite close 
to the mathematical hybrid function syntax, but in Python, we're limited 
to explicitly using an if. If I were coding this, and I'm not, I'd wrap 
it in a function. One advantage of a state variable rather than a 
continuous time function is that we can do this:

def accel(state):
return {NO_BRAKING: 0.0,
LOW_BRAKING: 0.2,
MID_BRAKING: 0.425,
HIGH_BRAKING: 0.85}[state]


which is simple enough to skip using a function in the first place, and 
just use the dict lookup directly. But for a more general question you'll 
want acceleration as a function of time.

If you prefer if...elif over a dict, I'd still hide it in a function.


 Problem: Work out how far you'll go before the
 brakes reach full power, and how fast you'll be going at that point.

Given that problem, we actually only care about LOW_BRAKING and 
MID_BRAKING. The problem becomes quite simple:

At t=0, the train is travelling at u m/s and the brakes are applied with 
acceleration of 0.2m/s^2 for one second, then 0.425m/s^2 for an 
additional one second. What is the speed of the train after those two 
seconds, and the distance travelled.

This becomes a simple question for the four standard equations of motion:

(1) v = u + at
(2) s = 1/2(u + v)t
(3) s = ut + 1/2(at^2)
(4) v^2 = u^2 + 2as

Only (1) and (3) are needed.


The distance travelled in the first second is:

s1 = u - 0.1  m

and the speed of the train at that time becomes:

v = u - 0.2  m/s

Applying this for the second second gives:

s2 = (u - 0.2) - 0.2125  m

v = (u - 0.2) - 0.425  m/s

and the total distance:

s = s1 + s2


No programming required, just a calculator :-)

Given that solving the entire problem is barely five lines, writing code 
to do so is probably unnecessary.

The only thing I haven't done is check that the train isn't travelling so 
slowly that it comes to a complete halt within two seconds. I leave that 
as an exercise. (Hint: if the final speed is negative, the train came to 
a halt.)


 Here's how I currently have the code. The variable names are a tad long,
 as this was also part of me teaching my brother Python.

Whatever you used to post this, ate the indentation.

 # Already got the brakes fully on
 if mode==Brake2: distance_to_full_braking_power, speed_full_brake =
 0.0, curspeed
 # The brakes went on one second ago, they're nearly full elif
 mode==Brake1: distance_to_full_braking_power,

Re: Code style query: multiple assignments in if/elif tree

On Tue, Apr 1, 2014 at 3:26 PM, Steven D'Aprano st...@pearwood.info wrote:
 On Tue, 01 Apr 2014 01:33:09 +1100, Chris Angelico wrote:

 Call this a code review request, if you like. I'm wondering how you'd go
 about coding something like this.

 I wouldn't. I'd start off by analysing the problem, and putting it into
 the simplest format possible, and *then* start writing code if and only
 if needed. See below.

 The first mistake of computational mathematics is to do the computation
 before the mathematics, and the Holy Grail is to avoid the computation
 altogether.

Fair enough. :)

 Imagine you're in a train, and the brakes don't apply instantly. The
 definition, in the interests of passenger comfort,

 Ah, you're using comfort in the modern sense, i.e. what people used to
 call discomfort :-P

 The scenario you describe has (effectively) infinite rate-of-change-of-
 acceleration, often called jerk. (A jerk is a rapid change in
 acceleration.) Human comfort is (within reasonable limits) more affected
 by jerk than acceleration. The passengers will feel three quite
 distinctive jerks, one when the brakes are first applied (which is
 probably reasonable), then one at 1s, then again at 2s. That's not
 comfortable by any stretch of the imagination.

It actually is a smooth increase in deceleration, but I'm operating
the simulator on a 1s period, so it's actually an average across the
first second, and an average across the next second...

 is that the first
 second of brake application has an acceleration of 0.2 m/s/s, the next
 second has 0.425 m/s/s, and thereafter full effect of 0.85 m/s/s.

... so really, it's seeking upward from 0 to 0.85 according to some
curve, the details of which I'm not familiar with, but in terms of 1s
average accelerations, it's those figures. Actually even 1s resolution
is more than we need; the overall purpose is to get a calculated time
in minutes, so calculating to sub-second resolution (when, in reality,
this is trying to predict what a human will do) is massive overkill.

 You
 have a state variable that says whether the brakes have just been
 applied, have already been applied for at least two seconds, or haven't
 yet been applied at all.

 I wouldn't model it that way. Especially since you've missed at least one
 state :-) I'd model the acceleration as a function of time, otherwise you
 have to convert a time into a state. Nevertheless, if you insist, we can
 use a state variable instead:

   0 for state == BRAKES NOT APPLIED YET
 accel = { 0.2 for state == BRAKES ON FOR BETWEEN 0 AND 1 SECOND
   0.425 for STATE == BRAKES ON FOR BETWEEN 1 AND 2 SECOND
   0.85 for state == BRAKES ON FOR MORE THAN 2 SECONDS

 Implied, but not stated, is that once the train stops, acceleration also
 goes to zero -- the train does not start moving backwards.

Just been applied is poorly named; that's the state where the brakes
have been applied for 1 second so far. The other state (brakes not
applied yet) could be looking at powering (which follows a similar
curve in the opposite direction) or cruising (which has acceleration
of 0.0 m/s/s).

 Haskell has nifty pattern-matching syntax for this that looks quite close
 to the mathematical hybrid function syntax, but in Python, we're limited
 to explicitly using an if. If I were coding this, and I'm not, I'd wrap
 it in a function. One advantage of a state variable rather than a
 continuous time function is that we can do this:

 def accel(state):
 return {NO_BRAKING: 0.0,
 LOW_BRAKING: 0.2,
 MID_BRAKING: 0.425,
 HIGH_BRAKING: 0.85}[state]

That could be done, but with .get() to allow a default. I may well do that.

 Problem: Work out how far you'll go before the
 brakes reach full power, and how fast you'll be going at that point.

 Given that problem, we actually only care about LOW_BRAKING and
 MID_BRAKING. The problem becomes quite simple:

Right. The other state is zero distance and zero loss of speed.

 At t=0, the train is travelling at u m/s and the brakes are applied with
 acceleration of 0.2m/s^2 for one second, then 0.425m/s^2 for an
 additional one second. What is the speed of the train after those two
 seconds, and the distance travelled.

 This becomes a simple question for the four standard equations of motion:

 (1) v = u + at
 (2) s = 1/2(u + v)t
 (3) s = ut + 1/2(at^2)
 (4) v^2 = u^2 + 2as

 Only (1) and (3) are needed.

Okay, what's u here? Heh.

 The distance travelled in the first second is:

 s1 = u - 0.1  m

 and the speed of the train at that time becomes:

 v = u - 0.2  m/s

 Applying this for the second second gives:

 s2 = (u - 0.2) - 0.2125  m

 v = (u - 0.2) - 0.425  m/s

 and the total distance:

 s = s1 + s2


 No programming required, just a calculator :-)

 Given that solving the entire problem is barely five lines, writing code
 to do so is probably unnecessary.

This is one small part of a larger piece of code (which, in this

Re: Python IM server

2014-03-31 Thread Miki Tebeka

   I want to develop a instant message server, simply has user and group 
 entity.
 Is there any better existing open-source one?
 Thus I can download and have a look.
You can take a look at Twisted Words 
(https://twistedmatrix.com/trac/wiki/TwistedWords).
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Re: Examples of modern GUI python programms

2014-03-31 Thread CM

On Sunday, March 30, 2014 7:16:07 PM UTC-4, D. Xenakis wrote:
 Id like to ask.. do you know any modern looking GUI examples of windows 
 software written in python? Something like this maybe: 
 http://techreport.com/r.x/asus-x79deluxe/software-oc.jpg (or hopefully 
 something like this android look: 
 http://chromloop.com/wp-content/uploads/2013/07/Skype-4.0-Android-screenshot.jpg).
 
 What i need is to develop an android looking program (entirelly in python) 
 for windows, but dunno if this is possible (most propably is), and which tool 
 between those would help me most: tkinter - wxpython - pyqt - pygtk .
 

I just know wxPython, so I'll discuss that.  I'm pretty sure you could achieve 
either of those with wxPython, but it isn't really set up to look like that 
(modern looking in your words) by default. wxPython is set up to look 
*native* for each platform it runs on. On WinXP, for example, toolbars and 
buttons generally have system gray backgrounds, but some widgets can be 
changed, some can't.  There are custom widgets that are more flexible though 
are not native.  

You could cleverly simulate these sorts of looks with creative use of 
library-included custom widgets, a few of your own custom widgets possibly, 
black backgrounds, drawing on a DC directly to the screen, image backgrounds, 
and a few other things (basically creating your own skin). The harder one is 
probably the first one you linked--the other, Skype on Android, is mostly just 
big fluffy images. Probably the first 90% of that is pretty easy and the last 
10% might be somewhat difficult, but not too bad.

It would be fun to try.
 
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Re: Python IM server

hint:
Tkinter
server db
update the tkinter apps, with the new data, after moving a line down


On Tue, Apr 1, 2014 at 1:06 AM, Miki Tebeka miki.teb...@gmail.com wrote:

I want to develop a instant message server, simply has user and group
 entity.
  Is there any better existing open-source one?
  Thus I can download and have a look.
 You can take a look at Twisted Words (
 https://twistedmatrix.com/trac/wiki/TwistedWords).
 --
 https://mail.python.org/mailman/listinfo/python-list




-- 
Best Regards,
David Hutto
*CEO:* *http://www.hitwebdevelopment.com http://www.hitwebdevelopment.com*
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Re: Code style query: multiple assignments in if/elif tree

2014-03-31 Thread Rustom Mody

On Tue, Apr 1, 2014 at 3:26 PM, Steven D'Aprano  wrote:

 Haskell has nifty pattern-matching syntax for this that looks quite close
 to the mathematical hybrid function syntax, but in Python, we're limited
 to explicitly using an if. If I were coding this, and I'm not, I'd wrap
 it in a function. One advantage of a state variable rather than a
 continuous time function is that we can do this:
 def accel(state):
 return {NO_BRAKING: 0.0,
 LOW_BRAKING: 0.2,
 MID_BRAKING: 0.425,
 HIGH_BRAKING: 0.85}[state]

Neat
I would put the dict in a variable. And those _BRAKINGs are GALLing me!

breaking = {NO:0.0, LOW:0.2, MID:0.425:, HIGH:0.85}
def accel(state): return breaking[state]

Irony
In using Haskell, I often wish for dicts especially python's nifty
dict-literals
/Irony

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[issue21104] Read from file aborted

2014-03-31 Thread Alex Grinko


Changes by Alex Grinko nitrog...@gmail.com:


--
resolution:  - works for me
status: open - closed

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[issue21108] Add examples for importlib in doc

2014-03-31 Thread Ned Deily


Changes by Ned Deily n...@acm.org:


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[issue1191964] asynchronous Subprocess

2014-03-31 Thread Glenn Linderman


Changes by Glenn Linderman v+pyt...@g.nevcal.com:


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[issue21085] compile error Python3.3 on Cygwin

2014-03-31 Thread dellair jie


dellair jie added the comment:

Yes, my pleasure. 

After configure on Cygwin, there is pyconfig.h generated, variables are as 
following:
/* #undef HAVE_SIGTIMEDWAIT */
/* #define HAVE_SIGWAITINFO 1 */

The error disappeared once changed HAVE_SIGWAITINFO to undef.
However, it encountered another issue mentioned here:
http://bugs.python.org/issue13756

The patches provided seem only for 3.2.2, not sure if it is ok to apply them 
directly on 3.3.2?

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[issue21109] tarfile: Traversal attack vulnerability

2014-03-31 Thread Daniel Garcia


New submission from Daniel Garcia:

The application does not validate the filenames inside the tar archive, 
allowing to extract files in arbitrary path. An attacker can craft a tar file 
to override files.

I've view this vulnerability in libtar:
http://lwn.net/Vulnerabilities/587141/
I've checked that python tarfile doesn't validate the filenames so python 
tarfile is vulnerable to this attack.

--
components: Library (Lib)
files: prevent-tar-traversal-attack.diff
keywords: patch
messages: 215222
nosy: Daniel.Garcia
priority: normal
severity: normal
status: open
title: tarfile: Traversal attack vulnerability
type: security
versions: Python 3.5
Added file: http://bugs.python.org/file34676/prevent-tar-traversal-attack.diff

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[issue21109] tarfile: Traversal attack vulnerability

2014-03-31 Thread Daniel Garcia


Daniel Garcia added the comment:

The solution in the patch is based on the gnutar solution to this, removing the 
prefix when extracting and adding.

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[issue21109] tarfile: Traversal attack vulnerability

2014-03-31 Thread Ned Deily


Ned Deily added the comment:

Setting as release blocker pending evaluation.

--
keywords: +security_issue
nosy: +benjamin.peterson, georg.brandl, larry, lars.gustaebel, ned.deily
priority: normal - release blocker
stage:  - test needed
versions: +Python 2.7, Python 3.1, Python 3.2, Python 3.3, Python 3.4

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[issue21109] tarfile: Traversal attack vulnerability

2014-03-31 Thread Christian Heimes


Christian Heimes added the comment:

It's a known and well-documented behavior of the tar module:

https://docs.python.org/2.7/library/tarfile.html#tarfile.TarFile.extractall

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[issue21109] tarfile: Traversal attack vulnerability

2014-03-31 Thread STINNER Victor


STINNER Victor added the comment:

 It's a known and well-documented behavior of the tar module

Would it possible to disable this behaviour by default, and only enable ti 
explicitly? The tar command line program has for example the -P / 
--absolute-paths option.

--
nosy: +haypo

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[issue21110] Slowdown and high memory usage when adding a new module in embedded Python 3.4 on 64bit Windows

2014-03-31 Thread MrValdez


New submission from MrValdez:

The example in the Extending Embedded Python 
(https://docs.python.org/3/extending/embedding.html#extending-embedded-python) 
takes up a lot of memory and slow downs the computer. I am using Windows 7 
64bit, Python 3.4 64bit and gcc (rubenvb-4.8.0) 4.8.0.

Solution:

Apparently, you need to add this to your C program:

#define HAVE_SSIZE_T

I found the solution at 
(https://forums.embarcadero.com/message.jspa?messageID=581594). The page said 
that when adding the above, this ensures that the type Py_ssize_t becomes 
__int64 instead of int.


Expected: 

The programmer should not see a simple program (that came from the main 
documentation, no less) causing slowdowns and high memory usage. The 64bit 
version of the Python installer was downloaded so the programmer should, at 
least, not need to know that they need this flag. 

Can the Python.h in the 64 bit builds automatically set the flag? Or, if this 
isn't feasible, add a note to the documentation that this flag exist.

--
components: Windows
messages: 215227
nosy: MrValdez
priority: normal
severity: normal
status: open
title: Slowdown and high memory usage when adding a new module in embedded 
Python 3.4 on 64bit Windows
type: performance
versions: Python 3.4

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[issue21110] Slowdown and high memory usage when adding a new module in embedded Python 3.4 on 64bit Windows

2014-03-31 Thread STINNER Victor


Changes by STINNER Victor victor.stin...@gmail.com:


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[issue20968] mock.MagicMock does not mock truediv

2014-03-31 Thread Johannes Baiter


Johannes Baiter added the comment:

Sorry for commenting so late, I submitted a version of the patch with unit 
tests roughly two weeks ago, I just forgot to mention it in a comment. Hereby 
fixed :-)

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[issue21082] os.makedirs(exist_ok=True) is not thread-safe: umask is set temporary to 0, serious security problem


Serhiy Storchaka added the comment:

See also issue19930. Behaviors of os.makedirs() and pathlib.Path.mkdir() are 
different. pathlib.Path.mkdir() (as the mkdir command) creates parent 
directories with default mode, and os.makedirs() - with specified mode.

--
nosy: +serhiy.storchaka

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[issue21044] tarfile does not handle file .name being an int


Serhiy Storchaka added the comment:

Does tarfile work with bytes file names?

I think a test should explicitly test file objects with str, bytes and int name 
and file objects without name in all write modes (w, w:gz, w|gz, etc).

--
nosy: +serhiy.storchaka

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[issue21044] tarfile does not handle file .name being an int


Changes by Serhiy Storchaka storch...@gmail.com:


--
stage: patch review - test needed

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[issue17846] Building Python on Windows - Supplementary info

2014-03-31 Thread Kathleen Weaver


Kathleen Weaver added the comment:

Patch from comments on March 29

--
Added file: http://bugs.python.org/file34677/win.patch

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[issue21085] compile error Python3.3 on Cygwin

2014-03-31 Thread dellair jie


dellair jie added the comment:

Applied the patch 0001-CYGWIN-issue13756-Python-make-fail-on-cygwin.patch in 
case: http://bugs.python.org/issue13756

The build failed with parser module:
building 'parser' extension
gcc -Wno-unused-result -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes 
-I./Include -I. -IInclude -I/cygdrive/c/temp/Python-3.3.2/Include 
-I/cygdrive/c/temp/Python-3.3.2 -c 
/cygdrive/c/temp/Python-3.3.2/Modules/parsermodule.c -o 
build/temp.cygwin-1.7.17-i686-3.3/cygdrive/c/temp/Python-3.3.2/Modules/parsermodule.o
gcc -shared -Wl,--enable-auto-image-base 
build/temp.cygwin-1.7.17-i686-3.3/cygdrive/c/temp/Python-3.3.2/Modules/parsermodule.o
 -L. -L/usr/local/lib -lpython3.3m -o 
build/lib.cygwin-1.7.17-i686-3.3/parser.dll
build/temp.cygwin-1.7.17-i686-3.3/cygdrive/c/temp/Python-3.3.2/Modules/parsermodule.o:
 In function `parser_sizeof':
/cygdrive/c/temp/Python-3.3.2/Modules/parsermodule.c:371: undefined reference 
to `__PyNode_SizeOf'
collect2: ld returned 1 exit status

Could anyone shed some lights please?

Br,
Li

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[issue17846] Building Python on Windows - Supplementary info

2014-03-31 Thread Kathleen Weaver


Kathleen Weaver added the comment:

New readme.txt patch

--
Added file: http://bugs.python.org/file34678/winreadme.patch

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[issue19655] Replace the ASDL parser carried with CPython

2014-03-31 Thread Eli Bendersky


Eli Bendersky added the comment:

Attaching patch that implements this. To make it easier, the patch only 
replaces the ASDL parser - not touching anything else and leaving the output 
intact.

With this patch applied, when the Makefile is rerun it regenerates the actual 
AST code in:

  Include/Python-ast.h
  Python/Python-ast.c

However, as the new parser generates exactly the same files, the code above is 
identical to the originals (hg diff shows nothing). In practice this means that 
no one building Python should notice this change, unless she's playing with the 
ASDL input file itself. The Makefile will not even regenerate these files 
unless the parser or the ASDL file were modified.

I have some additional ideas - to be delayed for subsequent patches:

1. The existing Spark-based parser didn't have tests, but my parser does. I'll 
do something similar to test_tools.py, as Benjamin suggested (to test the 
parser only in source builds).
2. The code of asdl_c.py could be modernized and be made even cleaner.
3. The same is true of the generated C code for the AST.

--
keywords: +patch
Added file: http://bugs.python.org/file34679/new-asdl-parser.issue19655.1.patch

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[issue20375] ElementTree: Document handling processing instructions

2014-03-31 Thread Eli Bendersky


Eli Bendersky added the comment:

The patch appears to contain code (tests) along with the documentation. Is this 
intended? This issue is not tagged properly if it is.

I'd suggest to split them to separate patches.

--
versions: +Python 3.5 -Python 2.7, Python 3.3, Python 3.4

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[issue21109] tarfile: Traversal attack vulnerability