Re: Help with some python homework...

[David]

On 1 February 2014 14:17, David bouncingc...@gmail.com wrote:

 Scott's message quoted above did not reach me, only Chris's quote of
 it, so I say: Scott once you begin a discussion on a mailing list like
 this one, please make sure that every reply you make goes to
 python-list@python.org and not to the individual. That way we can
 all participate in the discussion, that is best for everyone
 especially you.

Please disregard the above paragraph Scott. Because 8 messages from
you were just delivered to me, including that one, all via  the list,
some were 5 hours old. Sorry for any confusion I caused due to that
delay.
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Re: __init__ is the initialiser

[Ethan Furman]

On 01/31/2014 09:51 PM, Steven D'Aprano wrote:

On Sat, 01 Feb 2014 15:35:17 +1100, Chris Angelico wrote:


The two methods could have been done as a single method, __construct__,
in which you get passed a cls instead of a self, and you call
self=super().__construct__() and then initialize stuff.


That would be called __new__ in Python. There's no *need* to use __init__
for anything (except old-style classic classes in Python 2).


While there may not be a /need/ for two, having two is quite handy.  Having __new__ take care of the nuts and bolts (or 
foundation, as Terry put it), and being able to further customize with __init__ (where the kitchen goes, how many 
bedrooms, to follow along with Terry) is quite useful.  One of my favorite Enum recipes uses that pattern to have some 
basic behavior, with some other behavior that is easily overridable/extendable [1].


--
~Ethan~

[1] http://stackoverflow.com/q/19330460/208880
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Re: Python shell wont open idle or an exisiting py file

[Terry Reedy]

On 2/1/2014 2:26 AM, Chris Angelico wrote:

On Sat, Feb 1, 2014 at 4:46 PM, Terry Reedy tjre...@udel.edu wrote:

On 1/31/2014 10:36 PM, Chris Angelico wrote:


On Sat, Feb 1, 2014 at 1:54 PM, MRAB pyt...@mrabarnett.plus.com wrote:


I think that some years ago I heard about a variation on UTF-8
(Microsoft?) where codepoint U+ is encoded as 0xC0 0x80 so that the
null byte can be used as the string terminator.

I had a look on Wikipedia found this:

http://en.wikipedia.org/wiki/Null-terminated_string



Yeah, it's a common abuse of UTF-8. It's a violation of spec, but an
understandable one. However, I don't understand why the first part -
why should \0 become U+ but (presumably) the \a later on
(...cs\accel...) doesn't become U+0007, etc?



Because only  \0 has a special meaning in a C string,


I should have added 'to C itself', as the string terminator.


and Tk is written in C and uses C strings.


Eh? I've used \a in C programs (not often but I have used it).

It's possible that \0 is the only one that actually bombs anything
(because of C0 80 representation).


\0 can bomb C byte processing by terminating it sooner than it should. 
Its unexpected replacement bombs utf-8 decoding.


 But since \7 and \a both represent

0x07 in a C string, I would expect there to be other problems, if it's
interpreting it as source. Ah well! Weird weird.


While other control codes may have special meaning to a terminal or 
other device, to do not have special meaning to the operation of C 
string functions themselves (except possible for a 'getline' function 
looking for n -- but I do not remember is the C stdlib has any such 
functions).


I am speaking from my memory of C. I have not looked at the Tk C code to 
see just what it did where to create the exception. I am just happy that 
Serhiy was able to fixed tkinter without causing another test to fail.


--
Terry Jan Reedy

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Re: Python shell wont open idle or an exisiting py file

[Chris Angelico]

On Sat, Feb 1, 2014 at 7:51 PM, Terry Reedy tjre...@udel.edu wrote:
 I should have added 'to C itself', as the string terminator.

Oh, right. Yes, in that sense \0 is special. It's still wrong that an
incoming text string gets interpreted as code, but that's probably
just a consequence of the jump from Python to Tcl.

ChrisA
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Re: fseek In Compressed Files

[Dave Angel]

 Ayushi Dalmia ayushidalmia2...@gmail.com Wrote in message:

 
 The size of this file will be 10 GB. The version of Python I am using is 
 2.7.2. Yes, performance is an important issue. 
 

Then the only viable option is to extract the entire file and
 write it to a temp location. Perhaps as you extract it, you could
 also build a list of offsets,  so the seeking by line number can
 be efficient. 
-- 
DaveA

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C++ to python for LED Matrix

[Liam Knott]

Hey folks,

So the last week or so I've been searching this site for information on how to 
control and program a LED Matrix (or a number of them) for a project. A few 
Topics have caught my eye, with me originally having in mind using a Maxim 
MAX7221 to control the matrix, but none more than Klaas's: 
http://www.raspberrypi.org/phpBB3/viewtopic.php?t=41713.
This was almost perfect for me, until I saw the code was in C++ and from the 
title all I know is Python. So after checking the code out and trying to figure 
how this language works I just couldn't break it down and Unfortunately I don't 
have a lot of time to learn C++ ( would be great if I could but I don't have 
that luxury right now).
So if anyone is willing to check Klaas's topic and code and convert it into 
python that would be awesome, even if someone would explain how the code is 
working that would be great, oh and don't be scared to comment on ways of going 
about this project.

Note: Hoping I could achieve something like this but with the Pi: 
http://www.youtube.com/watch?v=FzHT-L-7jIA

Cheers!

Lknott :-D
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piping with subprocess

[Rick Dooling]

I spent half a day trying to convert this bash script (on Mac)

textutil -convert html $1 -stdout | pandoc -f html -t markdown -o $2

into Python using subprocess pipes.

It works if I save the above into a shell script called convert.sh and then do

subprocess.check_call([convert.sh, file, markdown_file]) 

where file and markdown_file are variables.

But otherwise my piping attempts fail.

Could someone show me how to pipe in subprocess. Yes, I've read the doc, 
especially

http://docs.python.org/2/library/subprocess.html#replacing-shell-pipeline

But I'm a feeble hobbyist, not a computer scientist.

Thanks

RD
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Re: __init__ is the initialiser

[Ned Batchelder]

On 1/31/14 10:42 PM, Steven D'Aprano wrote:

On Fri, 31 Jan 2014 14:52:15 -0500, Ned Batchelder wrote:


Why can't we call __init__ the constructor and __new__ the allocator?


__new__ constructs the object, and __init__ initialises it. What's wrong
with calling them the constructor and initialiser? Is this such a
difficult concept that the average programmer can't learn it?

I've met people who have difficulty with OOP principles, at least at
first. But once you understand the idea of objects, it isn't that hard to
understand the idea that:

- first, the object has to be created, or constructed, or allocated
   if you will;

- only then can it be initialised.

Thus, two methods. __new__ constructs (creates, allocates) a new object;
__init__ initialises it after the event.

(In hindsight, it was probably a mistake for Python to define two create-
an-object methods, although I expect it was deemed necessary for
historical reasons. Most other languages make do with a single method,
Objective-C being an exception with alloc and init methods.)



Earlier in this post, you wrote:


But that distinction [between __new__ and __init__] isn't useful in
most programs.


Well, I don't know about that. I guess it depends on what sort of objects
you're creating. If you're creating immutable objects, then the
distinction is vital. If you're subclassing from immutable built-ins, of
which there are a few, the distinction may be important. If you're using
the object-pool design pattern, the distinction is also vital. It's not
*rare* to care about these things.



The thing most people mean by constructor is the method that gets
invoked right at the beginning of the object's lifetime, where you can
add code to initialize it properly.  That describes __init__.


Most people. I presume you've done a statistically valid survey then
*wink*

It *better* describes __new__, because it is *not true* that __init__
gets invoked right at the beginning of the object's lifetime. Before
__init__ is invoked, the object's lifetime has already begun, inside the
call to __new__. Excluding metaclass shenanigans, the object lifetime
goes:


Prior to the object existing:
- static method __new__ called on the class[1]
- __new__ creates the object[2]  === start of object lifetime

Within the object's lifetime:
- the rest of the __new__ method runs, which may perform arbitrarily
   complex manipulations of the object;
- __new__ exits, returning the object
- __init__ runs


So __init__ does not occur *right at the beginning*, and it is completely
legitimate to write your classes using only __new__. You must use __new__
for immutable objects, and you may use __new__ for mutable ones. __init__
may be used by convention, but it is entirely redundant.

I do not buy the argument made by some people that Python ought to follow
whatever (possibly inaccurate or misleading) terminology other languages
use. Java and Ruby have the exact same argument passing conventions as
Python, but one calls it call by value and the other call by
reference, and neither is the same meaning of call by value/reference
as used by Pascal, C, Visual Basic, or other languages. So which
terminology should Python use? Both C++ and Haskell have functors, but
they are completely different things. What Python calls a class method,
Java calls a static method. We could go on for days, just listing
differences in terminology.

In Python circles, using constructor for __new__ and initialiser for
__init__ are well-established. In the context of Python, they make good
sense: __new__ creates (constructs) the object, and __init__
_init_ialises it. Missing the opportunity to link the method name
__init__ to *initialise* would be a mistake.

We can decry the fact that computer science has not standardised on a
sensible set of names for concepts, but on the other hand since the
semantics of languages differ slightly, it would be more confusing to try
to force all languages to use the same words for slightly different
concepts.

The reality is, if you're coming to Python from another language, you're
going to have to learn a whole lot of new stuff anyway, so having to
learn a few language-specific terms is just a small incremental cost. And
if you have no idea about other languages, then it is no harder to learn
that __new__ / __init__ are the constructor/initialiser than it would be
to learn that they are the allocator/constructor or preformulator/
postformulator.

I care about using the right terminology that will cause the least amount
of cognitive dissonance to users' understanding of Python, not whether
they have to learn new terminology, and in the context of Python's object
module, constructor and initialiser best describe what __new__ and
__init__ do.



My summary of our two views is this:  I am trying to look at things from 
a typical programmer's point of view.  The existence of __new__ is an 
advanced topic that many programmers never encounter.  Taking a quick 
scan through some 

Re: piping with subprocess

[Peter Otten]

Rick Dooling wrote:

 I spent half a day trying to convert this bash script (on Mac)
 
 textutil -convert html $1 -stdout | pandoc -f html -t markdown -o $2
 
 into Python using subprocess pipes.
 
 It works if I save the above into a shell script called convert.sh and
 then do
 
 subprocess.check_call([convert.sh, file, markdown_file])
 
 where file and markdown_file are variables.
 
 But otherwise my piping attempts fail.

It is always a good idea to post your best effort failed attempt, if only 
to give us an idea of your level of expertise.

 Could someone show me how to pipe in subprocess. Yes, I've read the doc,
 especially
 
 http://docs.python.org/2/library/subprocess.html#replacing-shell-pipeline
 
 But I'm a feeble hobbyist, not a computer scientist.

Try to convert the example from the above page


output=`dmesg | grep hda`
# becomes
p1 = Popen([dmesg], stdout=PIPE)
p2 = Popen([grep, hda], stdin=p1.stdout, stdout=PIPE)
p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
output = p2.communicate()[0]


to your usecase. Namely, replace

[dmesg] -- [textutil, -convert, html, infile, -stdout]
[grep, hda] -- [pandoc, -f, html, -t, marktown, -o,
 outfile]

Don't forget to set

infile = ... 
outfile = ... 

to filenames (with absolute paths, to avoid one source of error).
If that doesn't work post the code you wrote along with the error messages.

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Re: piping with subprocess

[Daniel da Silva]

Try this:

from subprocess import check_output
import sys
check_output(textutil -convert html %s -stdout | pandoc -f html -t
markdown -o %s % sys.argv[1:3], shell=True)




On Sat, Feb 1, 2014 at 7:19 AM, Rick Dooling rpdool...@gmail.com wrote:

 I spent half a day trying to convert this bash script (on Mac)

 textutil -convert html $1 -stdout | pandoc -f html -t markdown -o $2

 into Python using subprocess pipes.

 It works if I save the above into a shell script called convert.sh and
 then do

 subprocess.check_call([convert.sh, file, markdown_file])

 where file and markdown_file are variables.

 But otherwise my piping attempts fail.

 Could someone show me how to pipe in subprocess. Yes, I've read the doc,
 especially

 http://docs.python.org/2/library/subprocess.html#replacing-shell-pipeline

 But I'm a feeble hobbyist, not a computer scientist.

 Thanks

 RD
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Re: piping with subprocess

[Rick Dooling]

On Saturday, February 1, 2014 6:54:09 AM UTC-6, Peter Otten wrote:
 Rick Dooling wrote:
 
 
 
  I spent half a day trying to convert this bash script (on Mac)
 
  
 
  textutil -convert html $1 -stdout | pandoc -f html -t markdown -o $2
 
  
 
  into Python using subprocess pipes.
 
  
 
  It works if I save the above into a shell script called convert.sh and
 
  then do
 
  
 
  subprocess.check_call([convert.sh, file, markdown_file])
 
  
 
  where file and markdown_file are variables.
 
  
 
  But otherwise my piping attempts fail.
 
 
 
 It is always a good idea to post your best effort failed attempt, if only 
 
 to give us an idea of your level of expertise.
 
 
 
  Could someone show me how to pipe in subprocess. Yes, I've read the doc,
 
  especially
 
  
 
  http://docs.python.org/2/library/subprocess.html#replacing-shell-pipeline
 
  
 
  But I'm a feeble hobbyist, not a computer scientist.
 
 
 
 Try to convert the example from the above page
 
 
 
 
 
 output=`dmesg | grep hda`
 
 # becomes
 
 p1 = Popen([dmesg], stdout=PIPE)
 
 p2 = Popen([grep, hda], stdin=p1.stdout, stdout=PIPE)
 
 p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
 
 output = p2.communicate()[0]
 
 
 
 
 
 to your usecase. Namely, replace
 
 
 
 [dmesg] -- [textutil, -convert, html, infile, -stdout]
 
 [grep, hda] -- [pandoc, -f, html, -t, marktown, -o,
 
  outfile]
 
 
 
 Don't forget to set
 
 
 
 infile = ... 
 
 outfile = ... 
 
 
 
 to filenames (with absolute paths, to avoid one source of error).
 
 If that doesn't work post the code you wrote along with the error messages.

p1 = subprocess.Popen([textutil, -convert, html, file], 
stdout=subprocess.PIPE)
p2 = subprocess.check_call([pandoc, -f, html, -t, markdown, -o, 
markdown_file], stdin=p1.stdout, stdout=subprocess.PIPE)
p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
output = p2.communicate()[0]

Errors

Traceback (most recent call last):
  File /Users/me/Python/any2pandoc.py, line 70, in module
convert_word_file(file, markdown_file)
  File /Users/me/Python/any2pandoc.py, line 59, in convert_word_file
output = p2.communicate()[0]
AttributeError: 'int' object has no attribute 'communicate'

I get a markdown_file created but it's empty.

Thanks,

RD

ps - Daniel's works fine but I still don't learn to pipe :)


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Re: piping with subprocess

[Rick Dooling]

On Saturday, February 1, 2014 7:54:34 AM UTC-6, Rick Dooling wrote:
 On Saturday, February 1, 2014 6:54:09 AM UTC-6, Peter Otten wrote:
 
  Rick Dooling wrote:
 
  
 
  
 
  
 
   I spent half a day trying to convert this bash script (on Mac)
 
  
 
   
 
  
 
   textutil -convert html $1 -stdout | pandoc -f html -t markdown -o $2
 
  
 
   
 
  
 
   into Python using subprocess pipes.
 
  
 
   
 
  
 
   It works if I save the above into a shell script called convert.sh and
 
  
 
   then do
 
  
 
   
 
  
 
   subprocess.check_call([convert.sh, file, markdown_file])
 
  
 
   
 
  
 
   where file and markdown_file are variables.
 
  
 
   
 
  
 
   But otherwise my piping attempts fail.
 
  
 
  
 
  
 
  It is always a good idea to post your best effort failed attempt, if only 
 
  
 
  to give us an idea of your level of expertise.
 
  
 
  
 
  
 
   Could someone show me how to pipe in subprocess. Yes, I've read the doc,
 
  
 
   especially
 
  
 
   
 
  
 
   http://docs.python.org/2/library/subprocess.html#replacing-shell-pipeline
 
  
 
   
 
  
 
   But I'm a feeble hobbyist, not a computer scientist.
 
  
 
  
 
  
 
  Try to convert the example from the above page
 
  
 
  
 
  
 
  
 
  
 
  output=`dmesg | grep hda`
 
  
 
  # becomes
 
  
 
  p1 = Popen([dmesg], stdout=PIPE)
 
  
 
  p2 = Popen([grep, hda], stdin=p1.stdout, stdout=PIPE)
 
  
 
  p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
 
  
 
  output = p2.communicate()[0]
 
  
 
  
 
  
 
  
 
  
 
  to your usecase. Namely, replace
 
  
 
  
 
  
 
  [dmesg] -- [textutil, -convert, html, infile, -stdout]
 
  
 
  [grep, hda] -- [pandoc, -f, html, -t, marktown, -o,
 
  
 
   outfile]
 
  
 
  
 
  
 
  Don't forget to set
 
  
 
  
 
  
 
  infile = ... 
 
  
 
  outfile = ... 
 
  
 
  
 
  
 
  to filenames (with absolute paths, to avoid one source of error).
 
  
 
  If that doesn't work post the code you wrote along with the error messages.
 
 
 
 p1 = subprocess.Popen([textutil, -convert, html, file], 
 stdout=subprocess.PIPE)
 
 p2 = subprocess.check_call([pandoc, -f, html, -t, markdown, -o, 
 markdown_file], stdin=p1.stdout, stdout=subprocess.PIPE)
 
 p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
 
 output = p2.communicate()[0]
 
 
 
 Errors
 
 
 
 Traceback (most recent call last):
 
   File /Users/me/Python/any2pandoc.py, line 70, in module
 
 convert_word_file(file, markdown_file)
 
   File /Users/me/Python/any2pandoc.py, line 59, in convert_word_file
 
 output = p2.communicate()[0]
 
 AttributeError: 'int' object has no attribute 'communicate'
 
 
 
 I get a markdown_file created but it's empty.
 
 
 
 Thanks,
 
 
 
 RD
 
 
 
 ps - Daniel's works fine but I still don't learn to pipe :)

Okay, sorry. I fixed that obvious goof

p1 = subprocess.Popen([textutil, -convert, html, file], 
stdout=subprocess.PIPE)
p2 = subprocess.Popen([pandoc, -f, html, -t, markdown, -o, 
markdown_file], stdin=p1.stdout, stdout=subprocess.PIPE)
p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
output = p2.communicate()[0]

Now I get no errors, but I still get a blank markdown file.
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generator slides review

[andrea crotti]

I'm giving a talk tomorrow @Fosdem about generators/iterators/iterables..

The slides are here (forgive the strange Chinese characters):
https://dl.dropboxusercontent.com/u/3183120/talks/generators/index.html#3

and the code I'm using is:
https://github.com/AndreaCrotti/generators/blob/master/code/generators.py
and the tests:
https://github.com/AndreaCrotti/generators/blob/master/code/test_generators.py

If anyone has any feedback or want to point out I'm saying something
stupid I'd love to hear it before tomorrow (or also later I might give
this talk again).
Thanks
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Re: piping with subprocess

[Mark Lawrence]

On 01/02/2014 13:54, Rick Dooling wrote:

On Saturday, February 1, 2014 6:54:09 AM UTC-6, Peter Otten wrote:

Rick Dooling wrote:




I spent half a day trying to convert this bash script (on Mac)







textutil -convert html $1 -stdout | pandoc -f html -t markdown -o $2







into Python using subprocess pipes.







It works if I save the above into a shell script called convert.sh and



then do







subprocess.check_call([convert.sh, file, markdown_file])







where file and markdown_file are variables.







But otherwise my piping attempts fail.




It is always a good idea to post your best effort failed attempt, if only

to give us an idea of your level of expertise.




Could someone show me how to pipe in subprocess. Yes, I've read the doc,



especially







http://docs.python.org/2/library/subprocess.html#replacing-shell-pipeline







But I'm a feeble hobbyist, not a computer scientist.




Try to convert the example from the above page





output=`dmesg | grep hda`

# becomes

p1 = Popen([dmesg], stdout=PIPE)

p2 = Popen([grep, hda], stdin=p1.stdout, stdout=PIPE)

p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.

output = p2.communicate()[0]





to your usecase. Namely, replace



[dmesg] -- [textutil, -convert, html, infile, -stdout]

[grep, hda] -- [pandoc, -f, html, -t, marktown, -o,

  outfile]



Don't forget to set



infile = ...

outfile = ...



to filenames (with absolute paths, to avoid one source of error).

If that doesn't work post the code you wrote along with the error messages.


Would you please read and action this 
https://wiki.python.org/moin/GoogleGroupsPython to prevent us seeing the 
double line spacing above, thanks.


--
My fellow Pythonistas, ask not what our language can do for you, ask 
what you can do for our language.


Mark Lawrence

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Re: __init__ is the initialiser

[Roy Smith]

In article mailman.6275.1391257695.18130.python-l...@python.org,
 Ned Batchelder n...@nedbatchelder.com wrote:

 The existence of __new__ is an 
 advanced topic that many programmers never encounter.  Taking a quick 
 scan through some large projects (Django, edX, SQLAlchemy, mako), the 
 ratio of __new__ implementations to __init__ implementations ranges from 
 0% to 1.5%, which falls into rare territory for me. 

From our own codebase:

$ find . -name '*.py' | xargs grep 'def.*__new__' | wc -l
1
$ find . -name '*.py' | xargs grep 'def.*__init__' | wc -l
228

Doing the same searches over all the .py files in our virtualenv, I get 
2830 (__init__) vs. 50 (__new__).
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Re: __init__ is the initialiser

[Mark Lawrence]

On 01/02/2014 14:40, Roy Smith wrote:

In article mailman.6275.1391257695.18130.python-l...@python.org,
  Ned Batchelder n...@nedbatchelder.com wrote:


The existence of __new__ is an
advanced topic that many programmers never encounter.  Taking a quick
scan through some large projects (Django, edX, SQLAlchemy, mako), the
ratio of __new__ implementations to __init__ implementations ranges from
0% to 1.5%, which falls into rare territory for me.


 From our own codebase:

$ find . -name '*.py' | xargs grep 'def.*__new__' | wc -l
1
$ find . -name '*.py' | xargs grep 'def.*__init__' | wc -l
228

Doing the same searches over all the .py files in our virtualenv, I get
2830 (__init__) vs. 50 (__new__).



You could remove all 228 __init__ and still get your code to work by 
scattering object attributes anywhere you like, something I believe you 
can't do in C++/Java.  I doubt that you could remove the single __new__ 
and get your code to work.


--
My fellow Pythonistas, ask not what our language can do for you, ask 
what you can do for our language.


Mark Lawrence

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Python prime numbers

[Panagiotis Anastasiou]

Hi i'm new in programming and in python and i have an assignment that i cant 
complete. I have to Write a Python program to compute and print the first 200 
prime numbers. The output must be formatted with a title and the prime numbers 
must be printed in 5 properly aligned columns . I have used this code so far :

numprimes = raw_input('Prime Numbers  ')
count = 0
potentialprime = 2

def primetest(potentialprime):
divisor = 2
while divisor = potentialprime:
if potentialprime == 2:
return True
elif potentialprime % divisor == 0:
return False
break
while potentialprime % divisor != 0:
if potentialprime - divisor  1:
divisor += 1
else:
return True

while count  int(numprimes):
if primetest(potentialprime) == True:
print potentialprime
count += 1
potentialprime += 1
else:
potentialprime += 1

but i get the result in a single column . How can i get it in 5 rows? Can 
someone help please
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Re: piping with subprocess

[Rick Dooling]

On Saturday, February 1, 2014 8:00:59 AM UTC-6, Rick Dooling wrote:
 On Saturday, February 1, 2014 7:54:34 AM UTC-6, Rick Dooling wrote:
 
  On Saturday, February 1, 2014 6:54:09 AM UTC-6, Peter Otten wrote:
 
   Rick Dooling wrote:
 
I spent half a day trying to convert this bash script (on Mac)
textutil -convert html $1 -stdout | pandoc -f html -t markdown -o $2
into Python using subprocess pipes.
 
It works if I save the above into a shell script called convert.sh and
then do
  
subprocess.check_call([convert.sh, file, markdown_file])
 
where file and markdown_file are variables.
 
But otherwise my piping attempts fail.
 
   It is always a good idea to post your best effort failed attempt, if 
   only to give us an idea of your level of expertise.
Could someone show me how to pipe in subprocess. Yes, I've read the doc,
especially 
http://docs.python.org/2/library/subprocess.html#replacing-shell-pipeline
 
But I'm a feeble hobbyist, not a computer scientist.
 
   Try to convert the example from the above page
 
   
 
   output=`dmesg | grep hda`
 
   # becomes
 
   p1 = Popen([dmesg], stdout=PIPE)
 
   p2 = Popen([grep, hda], stdin=p1.stdout, stdout=PIPE)
 
   p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
 
   output = p2.communicate()[0]
 
   
 
   to your usecase. Namely, replace
 
   [dmesg] -- [textutil, -convert, html, infile, -stdout]
 
   [grep, hda] -- [pandoc, -f, html, -t, marktown, -o
   outfile]
 
   Don't forget to set
 
   infile = ... 
 
   outfile = ... 
 
   to filenames (with absolute paths, to avoid one source of error).
 
   If that doesn't work post the code you wrote along with the error 
   messages.
 
  p1 = subprocess.Popen([textutil, -convert, html, file], 
  stdout=subprocess.PIPE)
 
  p2 = subprocess.check_call([pandoc, -f, html, -t, markdown, -o, 
  markdown_file], stdin=p1.stdout, stdout=subprocess.PIPE)
 
  p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.

  output = p2.communicate()[0]
  Errors
  Traceback (most recent call last):
File /Users/me/Python/any2pandoc.py, line 70, in module
  convert_word_file(file, markdown_file)
File /Users/me/Python/any2pandoc.py, line 59, in convert_word_file
  output = p2.communicate()[0]
  AttributeError: 'int' object has no attribute 'communicate'
  I get a markdown_file created but it's empty.
  Thanks,
  RD
  ps - Daniel's works fine but I still don't learn to pipe :)
 Okay, sorry. I fixed that obvious goof

 p1 = subprocess.Popen([textutil, -convert, html, file], 
 stdout=subprocess.PIPE)
 
 p2 = subprocess.Popen([pandoc, -f, html, -t, markdown, -o, 
 markdown_file], stdin=p1.stdout, stdout=subprocess.PIPE)
 
 p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
 
 output = p2.communicate()[0]
 
 Now I get no errors, but I still get a blank markdown file.

Okay, blank lines removed. Apologies. I didn't know Google inserted them.

RD
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Re: Python prime numbers

[Larry Martell]

On Saturday, February 1, 2014, Panagiotis Anastasiou panas...@gmail.com
wrote:

 Hi i'm new in programming and in python and i have an assignment that i
 cant complete. I have to Write a Python program to compute and print the
 first 200 prime numbers. The output must be formatted with a title and the
 prime numbers must be printed in 5 properly aligned columns . I have used
 this code so far :

 numprimes = raw_input('Prime Numbers  ')
 count = 0
 potentialprime = 2

 def primetest(potentialprime):
 divisor = 2
 while divisor = potentialprime:
 if potentialprime == 2:
 return True
 elif potentialprime % divisor == 0:
 return False
 break
 while potentialprime % divisor != 0:
 if potentialprime - divisor  1:
 divisor += 1
 else:
 return True

 while count  int(numprimes):
 if primetest(potentialprime) == True:
 print potentialprime
 count += 1
 potentialprime += 1
 else:
 potentialprime += 1

 but i get the result in a single column . How can i get it in 5 rows? Can
 someone help please



If you put a comma at the end of the print statement it will suppress the
newline.
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Re: piping with subprocess

[Mark Lawrence]

On 01/02/2014 15:35, Rick Dooling wrote:


Okay, blank lines removed. Apologies. I didn't know Google inserted them.

RD



No problem, the whole snag is people don't know about this flaw in this 
tool until they're told about it.


--
My fellow Pythonistas, ask not what our language can do for you, ask 
what you can do for our language.


Mark Lawrence

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Re: __init__ is the initialiser

[Roy Smith]

 On 01/02/2014 14:40, Roy Smith wrote:
  In article mailman.6275.1391257695.18130.python-l...@python.org,
Ned Batchelder n...@nedbatchelder.com wrote:
 
  The existence of __new__ is an
  advanced topic that many programmers never encounter.  Taking a quick
  scan through some large projects (Django, edX, SQLAlchemy, mako), the
  ratio of __new__ implementations to __init__ implementations ranges from
  0% to 1.5%, which falls into rare territory for me.
 
   From our own codebase:
 
  $ find . -name '*.py' | xargs grep 'def.*__new__' | wc -l
  1
  $ find . -name '*.py' | xargs grep 'def.*__init__' | wc -l
  228
 
  Doing the same searches over all the .py files in our virtualenv, I get
  2830 (__init__) vs. 50 (__new__).

In article mailman.6280.1391267257.18130.python-l...@python.org,
 Mark Lawrence breamore...@yahoo.co.uk wrote:

 You could remove all 228 __init__ and still get your code to work by 
 scattering object attributes anywhere you like, something I believe you 
 can't do in C++/Java.

Why not?  Here's a simple C++ program which uses a constructor:

#include stdio.h

class Foo {
public:
int i;

Foo() : i(42) {}
};

int main(int, char**) {
Foo foo;
printf(foo.i = %d\n, foo.i);
}

If I wanted to, I could remove the constructor and still get my code to 
work by scattering object attributes anywhere I like:

#include stdio.h

class Foo {
public:
int i;
};

int main(int, char**) {
Foo foo;
foo.i = 42;
printf(foo.i = %d\n, foo.i);
}

 I doubt that you could remove the single __new__ and get your code to work.

Perhaps.  Looking at our own code, the one place we use __new__ is in a 
metaclass, which I think pretty well reinforces Ned's assertion that 
__new__ is an advanced topic.
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Re: generator slides review

[Miki Tebeka]

On Saturday, February 1, 2014 6:12:28 AM UTC-8, andrea crotti wrote:
 I'm giving a talk tomorrow @Fosdem about generators/iterators/iterables..
 
 
 
 The slides are here (forgive the strange Chinese characters):
 
 https://dl.dropboxusercontent.com/u/3183120/talks/generators/index.html#3
 
 
 
 and the code I'm using is:
 
 https://github.com/AndreaCrotti/generators/blob/master/code/generators.py
 
 and the tests:
 
 https://github.com/AndreaCrotti/generators/blob/master/code/test_generators.py
 
 
 
 If anyone has any feedback or want to point out I'm saying something
 
 stupid I'd love to hear it before tomorrow (or also later I might give
 
 this talk again).
 
 Thanks

My 2 cents:

slide 4:
[i*2 for i in range(10)]

slide 9:
while True:
try:
it = next(g)
body(it)
except StopIteration:
break

slide 21:
from itertools import count, ifilterfalse

def divided_by(p):
return lambda n: n % p == 0

def primes():
nums = count(2)
while True:
p = next(nums)
yield p
nums = ifilterfalse(divided_by(p), nums)



Another resource you can point to is http://www.dabeaz.com/generators/

Good luck.
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Re: piping with subprocess

[Peter Otten]

Rick Dooling wrote:

 On Saturday, February 1, 2014 6:54:09 AM UTC-6, Peter Otten wrote:

 Try to convert the example from the above page
 
 
 output=`dmesg | grep hda`
 # becomes
 p1 = Popen([dmesg], stdout=PIPE)
 p2 = Popen([grep, hda], stdin=p1.stdout, stdout=PIPE)
 p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
 output = p2.communicate()[0]
 
 
 to your usecase. Namely, replace
 
 [dmesg] -- [textutil, -convert, html, infile, -stdout]
 [grep, hda] -- [pandoc, -f, html, -t, marktown, -o,
  outfile]
 
 Don't forget to set
 
 infile = ...
 outfile = ...
 
 to filenames (with absolute paths, to avoid one source of error).
 If that doesn't work post the code you wrote along with the error
 messages.
 
 p1 = subprocess.Popen([textutil, -convert, html, file],
 stdout=subprocess.PIPE) 
 p2 = subprocess.check_call([pandoc, -f,
 html, -t, markdown, -o, markdown_file], stdin=p1.stdout,
 stdout=subprocess.PIPE)
 p1.stdout.close()  # Allow p1 to receive a SIGPIPE if p2 exits.
 output = p2.communicate()[0]
 
 Errors
 
 Traceback (most recent call last):
   File /Users/me/Python/any2pandoc.py, line 70, in module
 convert_word_file(file, markdown_file)
   File /Users/me/Python/any2pandoc.py, line 59, in convert_word_file
 output = p2.communicate()[0]
 AttributeError: 'int' object has no attribute 'communicate'
 
 I get a markdown_file created but it's empty.

Well, you replaced the Popen() from the example with a check_call() which 
uses a Popen instance internally, but does not expose it. 

I recommend that you stick as closely to the example as possible until you 
have a working baseline version. I'd try

textutil = subprocess.Popen(
[textutil, -convert, html, file], 
stdout=subprocess.PIPE)
pandoc = subprocess.Popen(
[pandoc, -f, html, -t, markdown, -o, markdown_file],
stdin=textutil.stdout)

textutil.stdout.close()
pandoc.communicate()


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Chris Miles? TGBooleanFormWidget?

[Len Conrad]

trying to install zoner.

Needs 
http://www.psychofx.com/TGBooleanFormWidget/http://www.psychofx.com/TGBooleanFormWidget/
 but that's giving 502 Bad Gateway

can't find TGBooleanFormWidget anywhere else.

Suggestions?

Thanks
Len



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Re: Help with some python homework...

[Denis McMahon]

On Fri, 31 Jan 2014 18:14:31 -0700, Scott W Dunning wrote:

 little different from a few things you guys had mentioned.  For one, I
 got the correct time by calculating the number of time run and
 converting that into seconds then back out to hr:mn:sc.  I didn’t
 calculate from midnight.

 SECONDS = 1 MINUTES = 60 * SECONDS HOURS = 60 * MINUTES
 
 time_left_house = 6 * HOURS + 52 * MINUTES

This does actually calculate the time in seconds since midnight that you 
left the house

 miles_run_easy_pace = 2 * (8 * MINUTES + 15 * SECONDS)
 
 miles_run_fast_pace = 3 * (7 * MINUTES + 12 * SECONDS)
 
 time_returned_home = miles_run_easy_pace + miles_run_fast_pace +
 time_left_house

And this calculates the time in seconds since midnight that you returned 
home

So although you don't realise it, you are actually working in seconds 
since midnight, and then converting seconds back into hours, minutes and 
seconds.

-- 
Denis McMahon, denismfmcma...@gmail.com
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Tkinter widgets into classes.

[Lewis Wood]

I was wandering if I could dynamically change my GUI and after a few searches 
on Google found the grid_remove() function. What I'm wandering now is if there 
is a way to group a lot of widgets up into one, and then use the one 
grid_remove function which will remove them all.

Is it possible to do this in a class like this?

class group1:
label1=Label(text=Upon clicking the button).grid(row=0,column=0)
label2=Label(text=The menu will dynamically change).grid(row=1,column=0)

group1.grid_remove()


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Re: Help with some python homework...

[Denis McMahon]

On Fri, 31 Jan 2014 22:18:34 -0700, Scott W Dunning wrote:

 Any chance you guys could help with another question I have?  Below is a
 code to a different problem.  The only thing I don’t understand is why
 when calculating the 'discounted price’ you have to subtract 1?  Thanks
 again guys!

price_per_book = 24.95 
discount = .40 
quantity = 60 
discounted_price = (1-discount) * price_per_book 
shipping = 3.0 + (60 - 1) * .75
total_price = 60 * discounted_price + shipping 
print total_price, 'Total price'

You subtract 1 from the shipping price (which should be quantity - 1) to 
allow for the fact that the first book costs 3.0 snargles to ship, and 
extra books in the same shipment cost 0.75 snargles each.

So if the quantity is greater than one, the shipping cost is 3 snargles 
for the first book plus 0.75 snargles times (quantity minus one)

The discounted price needs to be the cost, not the discount.

If the discount is 0.4 (or 40%), then the cost is 0.6 (or 60%) of the 
list price. You are trying to calculate the cost, not the discount.

list_price = discounted_price + discount_amount

1.0 * list_price = 0.6 * list_price + 0.4 * list_price

Hence:

discounted_price = list_price - discount_amount

0.6 * list_price = 1.0  * list_price - 0.4 * list_price

so discounted_price = ( 1.0 - 0.4 ) * list_price

where 0.4 is the decimal fraction of the discount

-- 
Denis McMahon, denismfmcma...@gmail.com
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Re: Tkinter widgets into classes.

[archie65]

On Saturday, 1 February 2014 19:43:18 UTC, Lewis Wood  wrote:
 I was wandering if I could dynamically change my GUI and after a few searches 
 on Google found the grid_remove() function. What I'm wandering now is if 
 there is a way to group a lot of widgets up into one, and then use the one 
 grid_remove function which will remove them all.
 
 
 
 Is it possible to do this in a class like this?
 
 
 
 class group1:
 
 label1=Label(text=Upon clicking the button).grid(row=0,column=0)
 
 label2=Label(text=The menu will dynamically change).grid(row=1,column=0)
 
 
 
 group1.grid_remove()

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Re: Tkinter widgets into classes.

[archie65]

You become less of a a faget and stop sucking granni tranni pussi
dis shud help u lewl
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Re: __init__ is the initialiser

[Tim Delaney]

On 1 February 2014 23:28, Ned Batchelder n...@nedbatchelder.com wrote:

 You are looking at things from an accurate-down-to-the-last-footnote
 detailed point of view (and have provided some footnotes!).  That's a very
 valuable and important point of view.  It's just not how most programmers
 approach the language.


This is the *language reference* that is being discussed. It documents the
intended semantics of the language. We most certainly should strive to
ensure that it is accurate-down-to-the-last-footnote - any difference
between the reference documentation and the implementation is a bug in
either the documentation or the implementation.

Tim Delaney
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Re: Tkinter widgets into classes.

[Lewis Wood]

Oh and another question, say I make another window in the program itself using 
this:

def secondwindow():
root2=Tk()
root2.mainloop()

Would it be possible for me to use some code which would return True if one of 
these windows is currently up, or return False if the window is not up?
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Re: Tkinter widgets into classes.

[Dave Angel]

 Lewis Wood fluttershy...@gmail.com Wrote in message:
 Oh and another question, say I make another window in the program itself 
 using this:
 
 def secondwindow():
 root2=Tk()
 root2.mainloop()
 
 Would it be possible for me to use some code which would return True if one 
 of these windows is currently up, or return False if the window is not up?
 

No need. Only one at a time can be running,  and you won't return
 from this function till it's done.

To put it another way, you only want one mainloop in your code.
-- 
DaveA

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Re:Python prime numbers

[Dave Angel]

 Panagiotis Anastasiou panas...@gmail.com Wrote in message:
 Hi i'm new in programming and in python and i have an assignment that i cant 
 complete. I have to Write a Python program to compute and print the first 200 
 prime numbers. The output must be formatted with a title and the prime 
 numbers must be printed in 5 properly aligned columns . I have used this code 
 so far :
 
 numprimes = raw_input('Prime Numbers  ')
 count = 0
 potentialprime = 2
 
 def primetest(potentialprime):
 divisor = 2
 while divisor = potentialprime:
 if potentialprime == 2:
 return True
 elif potentialprime % divisor == 0:
 return False
 break
 while potentialprime % divisor != 0:
 if potentialprime - divisor  1:
 divisor += 1
 else:
 return True
 
 while count  int(numprimes):
 if primetest(potentialprime) == True:
 print potentialprime
 count += 1
 potentialprime += 1
 else:
 potentialprime += 1
 
 but i get the result in a single column . How can i get it in 5 rows? Can 
 someone help please
 


-- 
DaveA

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Re:Python prime numbers

[Dave Angel]

 Panagiotis Anastasiou panas...@gmail.com Wrote in message:
 Hi i'm new in programming and in python and i have an assignment that i cant 
 complete. I have to Write a Python program to compute and print the first 200 
 prime numbers. The output must be formatted with a title and the prime 
 numbers must be printed in 5 properly aligned columns . I have used this code 
 so far :
 
 numprimes = raw_input('Prime Numbers  ')
 count = 0
 potentialprime = 2
 
 def primetest(potentialprime):
 divisor = 2
 while divisor = potentialprime:
 if potentialprime == 2:
 return True
 elif potentialprime % divisor == 0:
 return False
 break
 while potentialprime % divisor != 0:
 if potentialprime - divisor  1:
 divisor += 1
 else:
 return True
 

There are several things wrong with this function,  and it's
 redundant enough that maybe none of them matter.  I'd test it
 carefully. 

 while count  int(numprimes):
 if primetest(potentialprime) == True:
 print potentialprime
 count += 1
 potentialprime += 1
 else:
 potentialprime += 1
 
 but i get the result in a single column . How can i get it in 5 rows? Can 
 someone help please
 

As has been pointed out,  you can use a trailing comma to suppress
 the implied newline for each print. 
Then you can add it back in every five items by checking count.

But you have a bigger problem,  lining up the columns.  Try using
 the string modulus operator, or 'format'.

-- 
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Re: Tkinter widgets into classes.

[Lewis Wood]

On Saturday, 1 February 2014 21:52:51 UTC, Dave Angel  wrote:
 Lewis Wood fluttershy...@gmail.com Wrote in message:
 
  Oh and another question, say I make another window in the program itself 
  using this:
 
  
 
  def secondwindow():
 
  root2=Tk()
 
  root2.mainloop()
 
  
 
  Would it be possible for me to use some code which would return True if one 
  of these windows is currently up, or return False if the window is not up?
 
  
 
 
 
 No need. Only one at a time can be running,  and you won't return
 
  from this function till it's done.
 
 
 
 To put it another way, you only want one mainloop in your code.
 
 -- 
 
 DaveA

But I can click the button Multiple times and it will create multiple windows?
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Re: Tkinter widgets into classes.

[Dave Angel]

 Lewis Wood fluttershy...@gmail.com Wrote in message:
 
 
(deleting doublespaced googlegroups trash)
 
 
 To put it another way, you only want one mainloop in your code.
 
 -- 
 
 DaveA
 
 But I can click the button Multiple times and it will create multiple windows?
 

Not using the function you showed. 

-- 
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Re: Tkinter widgets into classes.

[Lewis Wood]

On Saturday, 1 February 2014 22:26:17 UTC, Dave Angel  wrote:
 Lewis Wood fluttershy...@gmail.com Wrote in message:
 
  
 
  
 
 (deleting doublespaced googlegroups trash)
 
  
 
  
 
  To put it another way, you only want one mainloop in your code.
 
  
 
  -- 
 
  
 
  DaveA
 
  
 
  But I can click the button Multiple times and it will create multiple 
  windows?
 
  
 
 
 
 Not using the function you showed. 
 
 
 
 -- 
 
 DaveA

It does, this is the whole code:

from tkinter import *

root=Tk()
root.title(Second Root Testing)



def secondwindow():
root2=Tk()
root2.mainloop()


button1=Button(root,text=Root2,command=secondwindow).grid(row=0,column=0)



root.mainloop()

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Re: Python prime numbers

[Wiktor]

On Sat, 1 Feb 2014 07:33:47 -0800 (PST), Panagiotis Anastasiou wrote:

 Hi i'm new in programming and in python and i have an assignment that
 i cant complete. I have to Write a Python program to compute and print the 
 first 200 prime numbers. The output must be formatted with a title and the 
 prime numbers must be printed in 5 properly aligned columns . I have used 
 this 
 code so far :

  Hi,
  try out this code:

for i in range(200):
   print '{0:5}'.format(i),
   if (i-4) % 5 == 0:
   print

  Or maybe, if it's still unclear, try execute these lines:

print 'Hello {0}'.format('world')
print '|{0:30}|'.format('right')
print '|{0:30}|'.format('left')
print '|{0:^30}|'.format('center')
print '|{0:16}|'.format('right'),
print '|{0:16}|'.format('left'),
print '|{0:^16}|'.format('center')

  But still, it might be hard to implement this printing for..in loop while
you're verifying primes (in another loop), so maybe think about getting first
200 primes in while loop like you do (and only storing them in a list), and
then printing them out from this list in external for..in loop.



  Now, to your primetest() function. It may be good for small primes, but try
to verify with it, if 832475734579 is a prime. :)

 def primetest(potentialprime):
 divisor = 2
 while divisor = potentialprime:

  First of all, see that you rarely use this loop - you check this condition at
most two times. You end up for good in the second while loop.

 if potentialprime == 2:
 return True
 elif potentialprime % divisor == 0:
 return False
 break

  'break' after return is redundant - never executes

 while potentialprime % divisor != 0:
 if potentialprime - divisor  1:
 divisor += 1
 else:
 return True

  So, this is your main loop. Very inefficient. Think about that:
a) do you really have to check divisors up to the potentialprime? 
   Maybe there is a point, where you may say, that you've checked all 
   possibilities? Remember that a * b = b * a 
b) do you really have to check every divisor? I mean, increasing 
   it by 1 in every step?

-- 
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'py{}@wu{}em.pl'.format('wkm', 'ka')
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Re: Tkinter widgets into classes.

[albert visser]

On Sun, 02 Feb 2014 00:07:00 +0100, Lewis Wood fluttershy...@gmail.com  
wrote:



On Saturday, 1 February 2014 22:26:17 UTC, Dave Angel  wrote:

Lewis Wood fluttershy...@gmail.com Wrote in message:

(snip)


DaveA


It does, this is the whole code:

from tkinter import *

root=Tk()
root.title(Second Root Testing)



def secondwindow():
root2=Tk()
root2.mainloop()

this may seem to work, but you're starting a new event loop here instead  
of using the current one. I think you want to create another TopLevel()  
window here, not a new Tk instance.


button1=Button(root,text=Root2,command=secondwindow).grid(row=0,column=0)

Note that if you want to be able to actually use the button1 symbol, you  
have to break this statement up:


button1=Button(root,text=Root2,command=secondwindow)
button1.grid(row=0,column=0)

You can't shortcut this because grid() returns None.


root.mainloop()




--
Vriendelijke groeten / Kind regards,

Albert Visser

Using Opera's mail client: http://www.opera.com/mail/
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Re: generator slides review

[Terry Reedy]

On 2/1/2014 9:12 AM, andrea crotti wrote:

I'm giving a talk tomorrow @Fosdem about generators/iterators/iterables..

The slides are here (forgive the strange Chinese characters):
https://dl.dropboxusercontent.com/u/3183120/talks/generators/index.html#3

and the code I'm using is:
https://github.com/AndreaCrotti/generators/blob/master/code/generators.py
and the tests:
https://github.com/AndreaCrotti/generators/blob/master/code/test_generators.py

If anyone has any feedback or want to point out I'm saying something
stupid I'd love to hear it before tomorrow (or also later I might give
this talk again).


Comments:

The use is assert in the first slide seem bad in a couple of different 
respects.


The use of 'gen_even' before it is defined.

A generator expression evaluates (better than 'yields') to a generator, 
not just an iterator.


The definition of 'generator' copies the wrong and confused glossary 
entry. Generator functions return generators, which are iterators with 
extra behavior.


I would leave out For loop(2). The old pseudo-getitem iterator protocol 
is seldom explicitly used any more, in the say you showed.


In 'Even numbers', I have no idea what the complication of next_even() 
is about.


'Lazyness drawbacks' overflow_list is bizarre and useless.  overflow_gen 
is bizarre and buggy. If you are intentionally writing buggy code to 
make a point, label it as such on the slide.


Iterators just produce values. Generators can consume as well as produce 
values, which is why they can act as both iterators and coroutines.


@monocle
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Re: Tkinter widgets into classes.

[Terry Reedy]

Idle, which used tkinter, runs multiple windows in one process with one 
event loop. There is no reason I know of to run multiple event loops in 
one process, and if you do, the results will not be documented and might 
vary between runs or between different systems.


Idle can also be run multiple times in multiple processes, each with its 
own event loop. But there is seldom a reason to do that with the same 
version. On the other hand, I routinely have more than one version 
running in order to test code with multiple versions. I can even have 
the same file open in multiple versions.


--
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Re: __init__ is the initialiser

[Steven D'Aprano]

On Sun, 02 Feb 2014 07:09:14 +1100, Tim Delaney wrote:

 On 1 February 2014 23:28, Ned Batchelder n...@nedbatchelder.com wrote:

 You are looking at things from an accurate-down-to-the-last-footnote
 detailed point of view (and have provided some footnotes!).  That's a
 very valuable and important point of view.  It's just not how most
 programmers approach the language.


 This is the *language reference* that is being discussed. It documents
 the intended semantics of the language. We most certainly should strive
 to ensure that it is accurate-down-to-the-last-footnote - any difference
 between the reference documentation and the implementation is a bug in
 either the documentation or the implementation.

+1


-- 
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mapping objects

[Rita]

Hello,

I want to learn more about ORMs so I stumbled upon, SqlAlchemy.

If i had a JSON document (or XML, CSV, etc.._) is it possible to convert it
to a SQLAlchemy objects? I like the ability to query/filter (
http://docs.sqlalchemy.org/en/rel_0_9/orm/tutorial.html#common-filter-operators)
 the
data assuming I set up the proper schema.

Also, is this a valid way to use an ORM suite?





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Re: C++ to python for LED Matrix

[Michael Torrie]

Yes you could use Python for this sort of thing.  The link you posted is
just using a kernel spi driver that Python can write to just as well as
C++ can (via it's /dev/spidev0.0 file).  There is a python library that
can talk to SPI in Python on the pi:

http://www.100randomtasks.com/simple-spi-on-raspberry-pi

You still need to know some low-level stuff though.  Like hexadecimal,
binary bit-wise operations, etc.

Definitely talk to people on the Raspberry Pi forum.  They are doing
this stuff frequently.

Also don't be afraid of C.  Learn it. You'll be glad.  The code you
linked to looks more complicated than it really is. The ioctl stuff
looks complicated. But everything else is easy.  If it weren't for the
ioctl stuff, which I know can be translated to Python directly but I'm
not quite sure how at the moment, the rest of that code could be
transliterated into Python in very short order.  The trick is to make
the code more pythonic, and use classes when appropriate to encapsulate
things. I'd make a class that talks to SPI, for example. It would open
the file, set the ioctls, and then provide a basic interface for writing
to the bus.  Then from that I'd build another class that implements the
matrix abstraction, using SPI class for the low-level stuff.

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Re: __init__ is the initialiser

[Ben Finney]

Ned Batchelder n...@nedbatchelder.com writes:

 My summary of our two views is this: I am trying to look at things
 from a typical programmer's point of view.

Do you think the typical programmer will be looking in the language
reference? I don't.

 The existence of __new__ is an advanced topic that many programmers
 never encounter.

But when they do, the language reference had better be very clear on the
purpose of “__init__” and “__new__”.

 You are looking at things from an accurate-down-to-the-last-footnote
 detailed point of view (and have provided some footnotes!). That's a
 very valuable and important point of view. It's just not how most
 programmers approach the language.

Won't most programmers approach the language through (a) some example
code, (b) the tutorial, (c) the library reference? Those are appropriate
places for helpful simplifications and elisions.

 We are also both trying to reduce cognitive dissonance, but again, you
 are addressing language mavens who understand the footnotes, and I am
 trying to help the in-the-trenches people who have never encountered
 __new__ and are wondering why people are using funny words for the
 code they are writing.

Then I think your attempt to sacrifice precise terminology in the
langauge reference is misplaced. The in-the-trenches people won't see
it; and, when they go looking for it, they're likely to be wanting exact
language-maven-directed specifications.

 Finding names for things is hard, and it's impossible to please both
 ends of this spectrum.

Very true. That's why we have different documents for different
audiences. But yes, the terminology needs to hold up for both ends of
the spectrum, and naming is difficult.

-- 
 \ “If nature has made any one thing less susceptible than all |
  `\others of exclusive property, it is the action of the thinking |
_o__)  power called an idea” —Thomas Jefferson |
Ben Finney

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Re: Help with some python homework...

[Scott W Dunning]

Yeah you’re right I didn’t even notice that.  For some reason I just added the 
60 instead of using quantity which had been defined.  


On Feb 1, 2014, at 8:50 AM, Dennis Lee Bieber wlfr...@ix.netcom.com wrote:

 On Fri, 31 Jan 2014 22:18:34 -0700, Scott W Dunning swdunn...@cox.net
 declaimed the following:
 
 Any chance you guys could help with another question I have?  Below is a 
 code to a different problem.  The only thing I don’t understand is why when 
 calculating the 'discounted price’ you have to subtract 1?  Thanks again 
 guys!  
 
 
   Because the discount rate you have is the amount taken OFF the price.
 But you need the price AFTER removing the discount amount 100% (1.0) - 40%
 (0.4) discount = 60% (0.6) final price
 
 price_per_book = 24.95
 discount = .40
 quantity = 60
 discounted_price = (1-discount) * price_per_book
 shipping = 3.0 + (60 - 1) * .75
 total_price = 60 * discounted_price + shipping
 print total_price, 'Total price'
 
   You defined quantity but then never used it in the shipping and
 total_price lines.
 -- 
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wlfr...@ix.netcom.comHTTP://wlfraed.home.netcom.com/
 
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Re: mapping objects

[Cameron Simpson]

On 01Feb2014 20:46, Rita rmorgan...@gmail.com wrote:
 I want to learn more about ORMs so I stumbled upon, SqlAlchemy.
 
 If i had a JSON document (or XML, CSV, etc.._) is it possible to convert it
 to a SQLAlchemy objects? I like the ability to query/filter (
 http://docs.sqlalchemy.org/en/rel_0_9/orm/tutorial.html#common-filter-operators)
  the
 data assuming I set up the proper schema.

Well, not as directly as you might hope. As I recall, SQLAlchemy
ORMs provide an easy way to make objects representing database
entities and whose methods automatically drive the necessary SQL
actions to manipulate them.

On that basis, you won't get anywhere without loading up the
JSON/XML/etc, parsing it for relevant information (trivial with
CSV, less so for structured data like JSON or XML), and storing it
in a database. To which you then point SQLAlchemy.

So you're already doing the fiddly bit just to get stuff into the database.

The neat filter operations you cite are actually done by special
methods on the objects representing tables and columns. For example,

  User.name == None

is done via the __eq__ method of User.name. And they return
strings: bare SQL. The beauty of this is that one can write almost
idiomatic python, and SQLA will generate correct SQL in the right
dialect for the database backend, and with all the values correctly
escaped.

However, it does presume you _already_ have a backend that can be
queried with SQL.

 Also, is this a valid way to use an ORM suite?

Well, in principle sure. But SQLA won't do it for you directly. It really
is for data already stored in an SQL queriable database.

Your point about using SQLA's filter operations is right, _provided_
you have already loaded the original data into a database with the
right schema. If you've done that work, then SQLA may well serve
you well from that point on.

Cheers,
-- 
Cameron Simpson c...@zip.com.au

We knew Army cadets were involved because they cut through two fences
to get to the goats, and 15 feet away there was an unlocked gate.
- a director of sports information in the Navy, regarding the theft
  of some mascots from the Naval Academy by Army rivals
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[issue12915] Add inspect.locate and inspect.resolve

[Vinay Sajip]

Vinay Sajip added the comment:

Another question to consider: is inspect the best place for this? I don't think 
it is, because

(a) It's not really an inspection facility
(b) Importing inspect to get this functionality would pull in lots
of stuff which wouldn't be used in the typical use case.

I think it makes more sense for it to be in importlib. Accordingly adding Brett 
to nosy, for his thoughts.

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[issue20471] test_signature_on_class() of test_inspect fails on AMD64 FreeBSD 9.0 3.x buildbot

[Yury Selivanov]

Changes by Yury Selivanov yselivanov...@gmail.com:


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[issue20473] inspect.Signature no longer handles builtin classes correctly

[Yury Selivanov]

Yury Selivanov added the comment:

OK, I'll take a look tomorrow. Don't think it's related  to #20471 though, as 
in there, if fails to find a signature for the 'builtin.object' (but I may be 
wrong).

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[issue18622] reset_mock on mock created by mock_open causes infinite recursion

[Berker Peksag]

Changes by Berker Peksag berker.pek...@gmail.com:


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[issue20472] test_write_pty() of test_asyncio fails on x86 Tiger 3.x buildbot

[Ned Deily]

Ned Deily added the comment:

FYI, besides 10.4 (Tiger), the test also fails on OS X 10.5 but appears to pass 
on 10.6 and later releases.

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[issue20473] inspect.Signature no longer handles builtin classes correctly

[Yury Selivanov]

Yury Selivanov added the comment:

OK, there was no unit-test for this... looking into the problem, the first 
questing is: why is __text_signature__ is on the '_pickle.Pickler' object, not 
on '_pickle.Pickler.__init__'?

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[issue20474] test_socket failures on OS X due to fixed expected failures

[Ned Deily]

New submission from Ned Deily:

Three send timeout test cases in test_socket were changed by a4e4facad164 for 
Issue12958 to be expected failures on OS X because of observed failures on 
the OS X buildbots running OS X 10.6 (Snow Leopard) and earlier.

testInterruptedSendTimeout (test.test_socket.InterruptedSendTimeoutTest) ... 
unexpected success
testInterruptedSendmsgTimeout (test.test_socket.InterruptedSendTimeoutTest) ... 
unexpected success
testInterruptedSendtoTimeout (test.test_socket.InterruptedSendTimeoutTest) ... 
unexpected success

It seems that the platform bugs causing the failures were fixed in OS X 10.7 so 
that the expected failures no longer fail.  However, the change in behavior 
had not been noticed because, until the recent change to unittest in 
Issue20165, unittest did not fail when there were unexpected successes.  Now it 
does fail, causing test_socket to fail on OS X 10.7+ for 3.4.  On 3.3 the 
unexpected success failures are silently skipped.  The attached patch changes 
the test cases to be skipped for OS X versions prior to 10.7 rather than to 
always expect failure on OS X.

--
components: Tests
messages: 209882
nosy: larry, ncoghlan, ned.deily
priority: high
severity: normal
stage: patch review
status: open
title: test_socket failures on OS X due to fixed expected failures
versions: Python 3.3, Python 3.4

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[issue20474] test_socket failures on OS X due to fixed expected failures

[Ned Deily]

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


--
keywords: +patch
Added file: http://bugs.python.org/file33842/issue20474.patch

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[issue20474] test_socket failures on OS X due to fixed expected failures

[Ned Deily]

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


Added file: http://bugs.python.org/file33843/issue20474.patch

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[issue20474] test_socket failures on OS X due to fixed expected failures

[Ned Deily]

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


Removed file: http://bugs.python.org/file33842/issue20474.patch

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[issue20473] inspect.Signature no longer handles builtin classes correctly

[Larry Hastings]

Larry Hastings added the comment:

Because slots like tp_init and tp_call don't have docstrings.  So it has to go 
in the class's docstring.

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[issue12958] test_socket failures on Mac OS X

[Ned Deily]

Ned Deily added the comment:

FYI, the OS X platform bugs causing the three send timeout test failures were 
fixed in OS X 10.7 causing those test cases to have previously silently skipped 
unexpected successes.  See Issue20474 for more details.

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[issue20471] test_signature_on_class() of test_inspect fails on AMD64 FreeBSD 9.0 3.x buildbot

[Stefan Krah]

Stefan Krah added the comment:

The build is --without-doc-strings. That should do the trick.

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[issue20473] inspect.Signature no longer handles builtin classes correctly

[Larry Hastings]

Larry Hastings added the comment:

I meant to say slots like tp_new and tp_init.  But fwiw it's true of tp_call 
too.

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[issue20473] inspect.Signature no longer handles builtin classes correctly

[Larry Hastings]

Larry Hastings added the comment:

And, I don't see how your changes to inspect.py could have caused the failures 
on the buildbot either.  But, then, I don't see how *anything* could cause the 
failures on the buildbot.  And your changes to inspect.py happened at (I think) 
roughly the same time.  Correlation isn't causation, but it's all I have to go 
on right now.

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[issue20471] test_signature_on_class() of test_inspect fails on AMD64 FreeBSD 9.0 3.x buildbot

[Larry Hastings]

Larry Hastings added the comment:

Good thinking!  I don't know when I can get to it though, maybe Sunday.

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[issue20471] test_signature_on_class() of test_inspect fails on AMD64 FreeBSD 9.0 3.x buildbot

[Stefan Krah]

Stefan Krah added the comment:

I think you just need to use the @requires_docstrings decorator for
the test. -- To me the failure looks expected if there aren't any
docstrings.

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[issue20473] inspect.Signature no longer handles builtin classes correctly

[Larry Hastings]

Larry Hastings added the comment:

Stefan Krah suggests that the failure in 20473 is because that platform builds 
without docstrings, and the test requires them.  So that should be an easy fix.

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[issue20456] Argument Clinic rollup patch, 2014/01/31

[Vajrasky Kok]

Vajrasky Kok added the comment:

The converters argument in command line is still broken.

[sky@localhost cpython3.4]$ hg pull -u
pulling from http://hg.python.org/cpython
searching for changes
no changes found
[sky@localhost cpython3.4]$ ./python Tools/clinic/clinic.py --converters

Legacy converters:
Traceback (most recent call last):
  File Tools/clinic/clinic.py, line 4131, in module
sys.exit(main(sys.argv[1:]))
  File Tools/clinic/clinic.py, line 4063, in main
print('' + ' '.join(c for c in legacy if c[0].isupper()))
  File Tools/clinic/clinic.py, line 4063, in genexpr
print('' + ' '.join(c for c in legacy if c[0].isupper()))
IndexError: string index out of range

Unit test for exercising Tools/clinic/clinic.py using assert_python_ok would be 
good, but that deserves a dedicated ticket.

Here is the patch to fix the bug.

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Added file: 
http://bugs.python.org/file33844/fix_clinic_converters_cmd_line.patch

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[issue2008] cookielib lacks FileCookieJar class for Safari

[Hendrik]

Hendrik added the comment:

I found a solution for reading Safari cookies, but struggling around with hg 
diff. Because always when i typ hg diff Lib/http/cookiejar.py it returns me the 
complete file not only my changes..

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[issue12915] Add inspect.locate and inspect.resolve

[Brett Cannon]

Brett Cannon added the comment:

importlib.util.resolve_name() already exists for resolving an explicit relative 
import name to an absolute one, so closing this as out of date.

--
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status: open - closed

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[issue20440] Use Py_REPLACE/Py_XREPLACE macros

[Martin v . Löwis]

Martin v. Löwis added the comment:

I think Raymond's original concern still applies: The macros do add to the 
learning curve. I would personally expect that Py_REPLACE(op, op2) does an 
INCREF on op2, but it does not.

Explicit is better than implicit.

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[issue12915] Add inspect.locate and inspect.resolve

[Vinay Sajip]

Vinay Sajip added the comment:

 importlib.util.resolve_name() already exists

But that's not what the proposed functionality is for, is it? This covers 
finding values inside an imported module which can be accessed via a dotted 
path from the module globals.

--
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status: closed - open

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[issue17159] Remove explicit type check from inspect.Signature.from_function()

[Stefan Behnel]

Stefan Behnel added the comment:

Hmm, I now notice that I was mistaken about this working:

'''
import inspect

def test_isfunction():

 test_isfunction()
True

return inspect.isfunction(test_isfunction)
'''

It only worked in Cython's test suite because its test runner monkey patches 
inspect.isfunction, and I had completely forgotten about it. Sorry for the 
confusion.

The thing is that Cython's function type isn't really a Python function 
(obviously), it inherits from PyCFunction, so it should return True for 
isbuiltin(). A problem on our side prevented that. If I fix it up, then the 
newly added duck-typing code actually ends up not being used, because 
signature() tests for isbuiltin() first and runs into Signature.from_builtin(), 
which is the Argument Clinic code path that expects a textual signature 
representation. Cython functions don't have that, because they are compatible 
with Python functions.

This situation could be helped in inspect.signature() by reversing the test 
order, i.e. by changing this code

if _signature_is_builtin(obj):
return Signature.from_builtin(obj)

if isfunction(obj) or _signature_is_functionlike(obj):
# If it's a pure Python function, or an object that is duck type
# of a Python function (Cython functions, for instance), then:
return Signature.from_function(obj)

into this:

if isfunction(obj) or _signature_is_functionlike(obj):
# If it's a pure Python function, or an object that is duck type
# of a Python function (Cython functions, for instance), then:
return Signature.from_function(obj)

if _signature_is_builtin(obj):
return Signature.from_builtin(obj)

Would this be ok?

I would also argue that the implementation of _signature_is_builtin() is, well, 
not ideal, because what it should test for according to the comment at the top 
of the function is the existance of __text_signature__. Instead, it does 
several type tests, one of which goes wrong in this case.

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[issue19683] test_minidom has many empty tests

[Roundup Robot]

Roundup Robot added the comment:

New changeset fed468670866 by Mark Dickinson in branch '2.7':
Issue #19683: Add __closure__ and other missing attributes to function docs.
http://hg.python.org/cpython/rev/fed468670866

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[issue19863] Missing function attributes in 2.7 docs.

[Mark Dickinson]

Mark Dickinson added the comment:

New changeset fed468670866 by Mark Dickinson in branch '2.7':
Issue #19683: Add __closure__ and other missing attributes to function docs.
http://hg.python.org/cpython/rev/fed468670866

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[issue19683] test_minidom has many empty tests

[Mark Dickinson]

Mark Dickinson added the comment:

Whoops; wrong issue number.  That commit message was for issue 19863.

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[issue19863] Missing function attributes in 2.7 docs.

[Mark Dickinson]

Changes by Mark Dickinson dicki...@gmail.com:


--
resolution:  - fixed
stage: commit review - committed/rejected
status: open - closed

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[issue10740] sqlite3 module breaks transactions and potentially corrupts data

[Ronny Pfannschmidt]

Ronny Pfannschmidt added the comment:

could we please get the option to opt-out of that behaviour, as a extra 
connection option maybe

with the normal python sqlite bindings its impossible
to have database migrations work safely
which IMHO makes this a potential data-loss issue

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[issue10740] sqlite3 module breaks transactions and potentially corrupts data

[R. David Murray]

R. David Murray added the comment:

Opt out of what behavior?

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[issue12915] Add inspect.locate and inspect.resolve

[Brett Cannon]

Brett Cannon added the comment:

Importlib already has importlib.import_module() (since Python 2.7) and that's 
as far as I'm willing to go for finding a module by name. Anything past that is 
a getarr() call on the resulting module and thus not worth adding to importlib.

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[issue12915] Add inspect.locate and inspect.resolve

[Vinay Sajip]

Vinay Sajip added the comment:

 and thus not worth adding to importlib.

Okay, fair enough. It's not purely an import function, though partly related to 
imports.

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[issue17159] Remove explicit type check from inspect.Signature.from_function()

[Yury Selivanov]

Changes by Yury Selivanov yselivanov...@gmail.com:


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[issue10740] sqlite3 module breaks transactions and potentially corrupts data

[Ronny Pfannschmidt]

Ronny Pfannschmidt added the comment:

the sqlite binding deciding how to handle transactions

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[issue17444] multiprocessing.cpu_count() should use hw.availcpu on Mac OS X

[Antoine Pitrou]

Antoine Pitrou added the comment:

The current os.cpu_count implementation calls sysconf(_SC_NPROCESSORS_ONLN), 
which is apparently defined under OS X, and returns the number of online CPUs 
(logical?):
https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man3/sysconf.3.html

multiprocessing has been modified to re-use os.cpu_count(), so I suggest 
closing this issue as out-of-date.

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[issue20473] inspect.Signature no longer handles builtin classes correctly

[Yury Selivanov]

Yury Selivanov added the comment:

 Stefan Krah suggests that the failure in 20473 is because that platform 
 builds without docstrings, and the test requires them.  So that should be an 
 easy fix.

Good news ;) OK, I'll decorate the test.

 Because slots like tp_init and tp_call don't have docstrings.  So it has to 
 go in the class's docstring.

So what's going on and why is it broken:

- from_builtin wasn't checking the incoming 'func' argument's type, it started 
to work with its '__text_signature__' right away. That was fixed.

- in 'inspect.signature' we checked 

 (isinstance(obj, _NonUserDefinedCallables) or ismethoddescriptor(obj) or
isinstance(obj, type))

  so *classes* were tried in 'from_builtin' too.

And that's why it worked.  Any class (even used-defined in pure Python) that 
had '__text_signature__' was passed to the 'Signature.from_builtin' and it did 
the right job.

Now, I don't want to completely rollback my commits, as I still think that 
'from_builtin' should strictly check what object is it working with, and raise 
appropriate exceptions. What we need to do is to separate parsing of 
'__text_signature__' into a private inspect module helper, so that 
'from_builtin' becomes a tiny wrapper.  Then, in 'signature.inspect' we need to 
find a way of testing if the given object is a builtin class, and call the 
parsing helper on it if it has the '__text_signature__' attribute.

I'm looking into this.

BTW, are you sure we can't somehow add '__text_signature__' to builtin class' 
'__init__'?

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[issue17159] Remove explicit type check from inspect.Signature.from_function()

[Yury Selivanov]

Yury Selivanov added the comment:

 Would this be ok?

Probably. I need to take a closer look.

I'm not sure I like the idea that Cython functions are chimeras of some sort, 
i.e. they have a type of python builtin functions, hence, logically, 
Signature.from_builtin should work on them (and they have to follow 
__text_signature__ API), and on the other hand, they try to mimic pure python 
functions (being a builtin type) with all its guts like '__code__' object etc.  

Perhaps, what we need to do, is to modify 'Signature.from_builtin' to check for 
pure-python function duck type too, and fallback to 'Signature.from_function' 
in this case. Larry, Nick, what do you think?

 I would also argue that the implementation of _signature_is_builtin() is, 
 well, not ideal, because what it should test for according to the comment at 
 the top of the function is the existance of __text_signature__. Instead, it 
 does several type tests, one of which goes wrong in this case.

'from_builtin' needs to have those type checks. Duck typing is good, but some 
minimal type safety is good too.

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[issue20471] test_signature_on_class() of test_inspect fails on AMD64 FreeBSD 9.0 3.x buildbot

[Roundup Robot]

Roundup Robot added the comment:

New changeset b1f214165471 by Yury Selivanov in branch 'default':
inspect.tests: Fix tests to work on python built with '--without-doc-strings' 
#20471
http://hg.python.org/cpython/rev/b1f214165471

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[issue20471] test_signature_on_class() of test_inspect fails on AMD64 FreeBSD 9.0 3.x buildbot

[Yury Selivanov]

Changes by Yury Selivanov yselivanov...@gmail.com:


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[issue20471] test_signature_on_class() of test_inspect fails on AMD64 FreeBSD 9.0 3.x buildbot

[Yury Selivanov]

Yury Selivanov added the comment:

Should be OK now. Thank you guys for the report and for the hint of what was 
going on ;)

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[issue20473] inspect.Signature no longer handles builtin classes correctly

[Yury Selivanov]

Changes by Yury Selivanov yselivanov...@gmail.com:


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[issue17159] Remove explicit type check from inspect.Signature.from_function()

[Stefan Behnel]

Stefan Behnel added the comment:

 I'm not sure I like the idea that Cython functions are chimeras of
 some sort, i.e. they have a type of python builtin functions, hence,
 logically, Signature.from_builtin should work on them (and they have to
 follow __text_signature__ API), and on the other hand, they try to mimic
 pure python functions (being a builtin type) with all its guts like
 '__code__' object etc.

That's one way of looking at it. The way I see it is that CPython's builtin
functions should rather behave exactly like Python functions. The fact that
there is such a thing as a __text_signature__ and general special casing
of builtins is IMHO a rather annoying but truly long standing bug. The only
necessary difference is that one of them contains byte code and the other
doesn't, everything else should eventually be aligned.

 Perhaps, what we need to do, is to modify 'Signature.from_builtin' to
 check for pure-python function duck type too, and fallback to
 'Signature.from_function' in this case.

In any case, I think that a complete Python function(-like) interface
should always be preferred to work-arounds like __text_signature__,
regardless of where it comes from.

 'from_builtin' needs to have those type checks. Duck typing is good, but
 some minimal type safety is good too.

I don't really see why. The code doesn't seem to be doing that much more
than text processing of the __text_signature__, plus a tiny bit of
optional(!) attribute checking (__module__ and __self__).

The restrictive type checks appear to be the only thing that prevents users
from doing this:

class myfunc:
__text_signature__ = '(a,b,c,d)'

sig = Signature.from_builtin(myfunc())

Granted, the name of that method doesn't really fit well in that case, and
a simpler interface than having to define a class would also not hurt.

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[issue20288] HTMLParse handing of non-numeric charrefs broken

[Ezio Melotti]

Ezio Melotti added the comment:

Here's a patch against 2.7.

--
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Added file: http://bugs.python.org/file33845/issue20288.diff

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[issue20445] HAVE_BROKEN_NICE detected incorrectly due to configure.ac typo

[George Kouryachy]

George Kouryachy added the comment:

Oops, looks like my local build system artifact.

Thank you for your attention, all-clear.

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[issue17159] Remove explicit type check from inspect.Signature.from_function()

[Yury Selivanov]

Yury Selivanov added the comment:

 That's one way of looking at it. The way I see it is that CPython's builtin
 functions should rather behave exactly like Python functions. The fact that
 there is such a thing as a __text_signature__ and general special casing
 of builtins is IMHO a rather annoying but truly long standing bug. The only
 necessary difference is that one of them contains byte code and the other
 doesn't, everything else should eventually be aligned.

I see your point. I think that modifying 'from_builtin' as I suggested in my 
previous comment is the right thing to do. I'll make a new patch soon.

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[issue20288] HTMLParse handing of non-numeric charrefs broken

[Roundup Robot]

Roundup Robot added the comment:

New changeset 0d50b5851f38 by Ezio Melotti in branch '2.7':
#20288: fix handling of invalid numeric charrefs in HTMLParser.
http://hg.python.org/cpython/rev/0d50b5851f38

New changeset 32097f193892 by Ezio Melotti in branch '3.3':
#20288: fix handling of invalid numeric charrefs in HTMLParser.
http://hg.python.org/cpython/rev/32097f193892

New changeset 92b3928bfde1 by Ezio Melotti in branch 'default':
#20288: merge with 3.3.
http://hg.python.org/cpython/rev/92b3928bfde1

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[issue17159] Remove explicit type check from inspect.Signature.from_function()

[Stefan Behnel]

Stefan Behnel added the comment:

Attached is a minimal patch that does what I think you meant.

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Added file: http://bugs.python.org/file33846/divert_from_builtin.patch

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[issue20475] pystone.py in 3.4 still uses time.clock(), even though it's marked as deprecated since 3.3

[Paul Sokolovsky]

New submission from Paul Sokolovsky:

http://docs.python.org/3.3/library/time.html#time.clock says that it's 
deprecated, but pystone.py in Python-3.4.0b3 tarball still uses it. 

Please kindly consider switching it to plain time.time() and not to some other 
novelties.

My usecase is: I'm working on alternative Python implementation, I of course 
want to benchmark it, and of course want to claim that I ran unmodified 
pystone.py. Now to achieve that, I need to implement deprecated function.

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priority: normal
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title: pystone.py in 3.4 still uses time.clock(), even though it's marked as 
deprecated since 3.3
type: enhancement

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[issue20475] pystone.py in 3.4 still uses time.clock(), even though it's marked as deprecated since 3.3

[Paul Sokolovsky]

Changes by Paul Sokolovsky pfal...@users.sourceforge.net:


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versions: +Python 3.3, Python 3.4

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[issue10740] sqlite3 module breaks transactions and potentially corrupts data

[R. David Murray]

R. David Murray added the comment:

As noted above you get that by setting isolation_level to None.  That feature 
has always been available.  (With isolation_level set to None, the sqlite 
wrapper module itself never issues any BEGIN statements.)

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[issue17159] Remove explicit type check from inspect.Signature.from_function()

[Yury Selivanov]

Yury Selivanov added the comment:

Stefan,
Please try the attached patch (sig_cython_01.patch)

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[issue20475] pystone.py in 3.4 still uses time.clock(), even though it's marked as deprecated since 3.3

[STINNER Victor]

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


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[issue20400] Add create_read_pipe_protocol/create_write_pipe_protocol to asyncio.SubprocessProtocol

[Roundup Robot]

Roundup Robot added the comment:

New changeset d7ac90c0463a by Victor Stinner in branch 'default':
Issue #20400: Merge Tulip into Python: add the new asyncio.subprocess module
http://hg.python.org/cpython/rev/d7ac90c0463a

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