date:20150312

On Thu, 12 Mar 2015 16:31:12 +1100, Steven D'Aprano
 wrote:

>Mario Figueiredo wrote:
>
>
>If this is supposed to be a singleton, you can't create more instances. The 
>point of a singleton that there is only one instance (or perhaps a small 
>number, two or three say). Why do you need two different ways to create 
>instances if you only have one instance?
>

The map is instantiated from the contents of a saved map file on the
main application.

A different application, a map editor, needs to also instantiate an
object of the class Map. But in this case the map needs to either be
empty (if the user wants to create a new map), or loaded from the
saved map file (if the user wants to edit an existing map).

>
>> I added the following method to the class definition, above:
>> 
>> @classmethod
>> def generate(cls, width, height, fill=terrain[6]):
>> if Map._instance is None:
>> Map._instance = super(Map, cls).__new__(cls)
>> else:
>> raise Exception('Cannot generate an instance of Map.')
>> 
>> Map._instance.author = None
>> Map._instance.name = None
>
>Since this method modifies the singleton instance in place, it doesn't 
>generate a new instance. It shouldn't be called generate().

No sure what you mean. That method either creates a new instance or
raises an exception. It doesn't modify an instance in-place.

>
>> Map._instance.description = None
>>  # etc...
>>  self.cells = [Cell(fill)] * width * height
>> return Map._instance
>
>That's not your actual code, since the indentation is wrong.

 Map._instance.description = None
 # etc...
 self.cells = [Cell(fill)] * width * height
 return Map._instance
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Re: new() does not return anything, on singletong pattern

On Wed, 11 Mar 2015 16:47:32 -0700, Ethan Furman 
wrote:
>
>You're code is good.  

Thanks for taking a weight off my shoulder.

>
> The only question is if you /really/ need a singleton -- and only
> you can answer that (although plenty of folks will tell you you
> don't ;) .

Yeah. I debated that myself. But in the end the singleton won.

It's just a cheap global, since is ubiquitous throughout the entire
application, does behave like a singleton, and is a bit too expensive
to create. A full map in the main application takes 3 or 4 seconds to
instantiate and occupies around 2 Mb of memory.

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I want to get involved with Python!

2015-03-12 Thread bink...@mweb.co.za

Hi,

I am currently a "Progress Programmer" and looking for new challenges! It seems 
that Python is a good language to get familiar with and I would like some 
advice. I am on the look-out for a new job anyway and I thought it well to look 
for a job as Python developer in my field. I have been working in the 
healthcare sector for many years now and perhaps the only way to find a job as 
Python programmer at this stage, will be to find a job in the healthcare 
sector, as this is what I am familiar with. Are there any healthcare companies 
using Python (anywhere in the world) that I can contact for opportunities and 
advice?

I currently live in South Africa and would like to know what the demand for 
Python is in SA, but I will also consider relocating to Australia or the UK if 
I find it's going to be worth it.

Please advise on what route you would suggest I take to become a Python 
developer!

Thanks,
Bianca.
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Re: new() does not return anything, on singletong pattern

2015-03-12 Thread Gregory Ewing


Mario Figueiredo wrote:


It's just a cheap global, since is ubiquitous throughout the entire
application, does behave like a singleton, and is a bit too expensive
to create. A full map in the main application takes 3 or 4 seconds to
instantiate and occupies around 2 Mb of memory.


There's nothing wrong with having only one instance. The
quesion is whether it's a good idea to make calling Map()
be the way to get hold of that instance.

I would say it's counterproductive. The implementation
is convoluted, and it makes code that calls Map()
confusing, because it looks like it's creating a new
instance when it really isn't.

I would just provide a function:

_map = None

def get_map():
   global _map
   if _map is None:
  _map = Map()
   return _map

and document the fact that you shouldn't call Map()
directly.

--
Greg
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Re: new() does not return anything, on singletong pattern

2015-03-12 Thread Gregory Ewing


Mario Figueiredo wrote:


A different application, a map editor, needs to also instantiate an
object of the class Map. But in this case the map needs to either be
empty (if the user wants to create a new map), or loaded from the
saved map file (if the user wants to edit an existing map).


Then you have two functions for creating maps:

new_empty_map()

load_map_from_file(filename)

Both of these can complain if there is already a
Map instance.

--
Greg
--
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python-wheel distribution, add a local dependency which is not available in PyPi

2015-03-12 Thread remisharoon

Hi

I have a dependency of a local .whl file, which is not in Pypi.
How can I bundle that (local .whl file) inside the wheel file, so that inner 
.whl will get installed as a dependency.

In simple terms a wheel file inside another wheel file.
Can I add it as a package_data ? , if so how can get it automatically installed 
as a dependency?

Please help
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Re: new() does not return anything, on singletong pattern

2015-03-12 Thread Gregory Ewing


Mario Figueiredo wrote:

But PyCharm flags the assignment
with a warning telling me that generate() does not return anything and
the I lose code completion on the mmap variable.


My guess is that there is a syntax error somewhere
in your code that's confusing the IDE.

--
Greg
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Re: new() does not return anything, on singletong pattern

On Thu, 12 Mar 2015 21:38:00 +1300, Gregory Ewing
 wrote:

>
>I would just provide a function:
>
>_map = None
>
>def get_map():
>global _map
>if _map is None:
>   _map = Map()
>return _map
>
>and document the fact that you shouldn't call Map()
>directly.

Oh, you are so right! Been so long since I last created a singleton I
forgot all about the idiomatic approaches to the pattern.

Thanks Greg. That is much, much, better.
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RE: Re: I want to get involved with Python!

2015-03-12 Thread bink...@mweb.co.za

>https://en.wikipedia.org/wiki/OpenEdge_Advanced_Business_Language
 Yip, that's the one I am referring to, Terry.
From: tjre...@udel.edu
Sent: 2015/03/11 08:43:42 PM
To: python-list@python.org
Cc:
Subject: RE: Re: I want to get involved with Python!  On 3/11/2015 5:19 AM, 
bink...@mweb.co.za wrote:

> I am currently a "Progress Programmer" and looking for new challenges!

Are you referring to

https://en.wikipedia.org/wiki/OpenEdge_Advanced_Business_Language

> It seems that Python is a good language to get familiar with and I would
> like some advice. I am on the look-out for a new job anyway and I
> thought it well to look for a job as Python developer in my field. I
> have been working in the healthcare sector for many years now and
> perhaps the only way to find a job as Python programmer at this stage,
> will be to find a job in the healthcare sector, as this is what I am
> familiar with. Are there any healthcare companies using Python (anywhere
> in the world) that I can contact for opportunities and advice?
>
> I currently live in South Africa and would like to know what the demand
> for Python is in SA, but I will also consider relocating to Australia or
> the UK if I find it's going to be worth it.
>
> Please advise on what route you would suggest I take to become a Python
> developer!

One way to establish credibility as a 'python programmer' is to make 
contributions to an open-source python project. Perhaps find or create 
a project to somehow integrate Python and Progress.

-- 
Terry Jan Reedy

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EuroPython 2015: Early-Bird tickets sold out!

2015-03-12 Thread M.-A. Lemburg

We are very happy to announce that early-bird tickets are sold out!

 The tickets were sold in less than a week!

We’d like to thank everyone for the fantastic feedback. Given the rush
to the early-bird tickets (we sold 100 tickets in the first 4 hours),
we recommend to not wait too long before getting your standard
ticket. It is likely, we’ll sell out early again this year.

As announced we had temporarily closed the registration for a short
while today and have now reopened it with the standard rate prices:

 *** https://ep2015.europython.eu/en/registration/ ***

Enjoy,
--
EuroPython 2015 Team
http://www.europython-society.org/
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Re: new() does not return anything, on singletong pattern

On Thu, 12 Mar 2015 21:40:03 +1300, Gregory Ewing
 wrote:

>Mario Figueiredo wrote:
>
>> A different application, a map editor, needs to also instantiate an
>> object of the class Map. But in this case the map needs to either be
>> empty (if the user wants to create a new map), or loaded from the
>> saved map file (if the user wants to edit an existing map).
>
>Then you have two functions for creating maps:
>
>new_empty_map()
>
>load_map_from_file(filename)
>
>Both of these can complain if there is already a
>Map instance.

new_empty_map(width, height, fill=terrain['sea'])

load_map_from_file(filename)

These would be the most likely signatures for those functions. The
first function does not need to perform any of code to do with opening
and reading a binary file, verifying an hash for possible file data
corruption, filling the map header information and populating the
cells.

Both functions need to have knowledge of the Map class internals. Is
it pythonic to create those functions in the same module of the Map
class. Or because of how they have access to some "private" details of
the class they should instead be made static methods as a means to
signal that much?

Map.new()
Map.load()
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Re: when may sys.executable be empty

2015-03-12 Thread Terry Reedy


On 3/11/2015 10:41 AM, Wolfgang Maier wrote:

 From the documentation of sys.executable:

 A string giving the absolute path of the executable binary for the
Python interpreter, on systems where this makes sense. If Python is
unable to retrieve the real path to its executable, sys.executable will
be an empty string or None.

So on which systems does it not make sense ?


Importing tkinter in a Python program starts up an embedded tcl 
interpreter to run tk, but as far as I know, there is no tcl.exe on my 
system, only the tcl/tk .dlls.  I can imagine a similar situation with 
embedded python.  If a python interpreter is being run as an embedded 
interpreter *and* there is the same version of python.exe installed, I 
don't know what happens.


--
Terry Jan Reedy

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Re: Use à Python 2 module with Python 3

2015-03-12 Thread Ian Kelly

On Wed, Mar 11, 2015 at 11:30 AM, Michael Parchet  wrote:
> Hello,
>
> Only one file of pyside project has update at 10 fob,
>
> What's your opinion
>
> Pyside is ded ?

This thread has some discussion that would be useful in determining
the current state of the project:
https://groups.google.com/forum/#!topic/pyside-dev/weFDtFpgbzc

Summarizing, it seems that Digia is not interested in PySide
development, but there are a number of individuals who are. I'm not
sure what the actual progress is of the work described there.

PySide isn't dead. It's resting.

Would it be advisable to use it at the current time for a new project
that you intend to support into the future? Probably not.
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Re: Use à Python 2 module with Python 3

2015-03-12 Thread Michael Torrie

On 03/11/2015 11:30 AM, Michael Parchet wrote:
> Hello,
> 
> Only one file of pyside project has update at 10 fob,
> 
> What's your opinion
> 
> Pyside is ded ?

Qt 4 is very stable, with no new features.  PySide works very well for
me, and the few bugs/limitations that I know of can be worked around
quite easily, and it's trivial to maintain direct compatibility with
PyQt, so PyQt can always be a good fallback (remember PyQt is a
commercial product, so you must buy a license if you want to use it
under anything other than the GPL).

My biggest complaint with PySide is that for historical reasons (looking
at you, PyQt), it does not use pep8 naming conventions, which makes for
some really ugly function and method names.
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Re: Python3: Reading a text/binary mixed file

2015-03-12 Thread Paulo da Silva

On 11-03-2015 01:09, Cameron Simpson wrote:
> On 10Mar2015 22:38, Paulo da Silva  wrote:
>> On 10-03-2015 04:14, Cameron Simpson wrote:
...

> 
> Since binary files (returning bytes from reads) also have a convenient
> readline method looking for byte 10 ('\n') this makes you current task
> tractable
...

That was the big part of my problem.
I wrongly assumed that readline was not available in binary mode.
I should have tried it in first place :-)

Thanks

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Callbacks with concurrent.futures

2015-03-12 Thread Joseph L. Casale

I have a ProcessPoolExecutor for which I am attaching multiple callbacks.
As this must be process based and not thread based, I don't have the
luxury communication between threads. Without a queue, does something
inherent exist in concurrent futures that allows me to accumulate some
data from the final callback?

Thanks,
jlc
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Re: Callbacks with concurrent.futures

2015-03-12 Thread Ian Kelly

On Wed, Mar 11, 2015 at 1:32 PM, Joseph L. Casale
 wrote:
> I have a ProcessPoolExecutor for which I am attaching multiple callbacks.
> As this must be process based and not thread based, I don't have the
> luxury communication between threads. Without a queue, does something
> inherent exist in concurrent futures that allows me to accumulate some
> data from the final callback?

ProcessPoolExecutor is built on the multiprocessing module, so I
expect you should be able to use multiprocessing.Queue or
multiprocessing.Pipe in place of threading.Queue.
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Re: Callbacks with concurrent.futures

2015-03-12 Thread Joseph L. Casale

> ProcessPoolExecutor is built on the multiprocessing module, so I
> expect you should be able to use multiprocessing.Queue or
> multiprocessing.Pipe in place of threading.Queue.

Hi Ian,
Yeah I am using a Manager.Queue as the method polling the queue
is itself in a process.

I just wondered if there was some facility in the module that
provided communication or if I had to handle.

Thanks!
jlc
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ANN: eGenix mxODBC 3.3.2 - Python ODBC Database Interface

2015-03-12 Thread eGenix Team: M.-A. Lemburg



ANNOUNCING

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   Version 3.3.2


mxODBC is our commercially supported Python extension providing
 ODBC database connectivity to Python applications
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   with many advanced Python DB-API extensions and
 full support of stored procedures


This announcement is also available on our web-site for online reading:
http://www.egenix.com/company/news/eGenix-mxODBC-3.3.2-GA.html



INTRODUCTION

mxODBC provides an easy-to-use, high-performance, reliable and robust
Python interface to ODBC compatible databases such as MS SQL Server,
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The "eGenix mxODBC - Python ODBC Database Interface" product is a
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The 3.3.2 release of our mxODBC is a patch level release of our
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 * Fixed an "ODBC driver sent negative string size" error when using
   empty strings or None with output parameters for SQL Server ODBC
   drivers.

 * Clarified that due to the way the SQL Server ODBC driver sends
   data, mixing output parameters and output result sets is not
   possible. A work-around for this is to send back output parameters
   as additional result set.

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 * Added a work-around for the Sybase ASE ODBC driver which has
   problems with BIGINT columns. These are now supported.

 * Fixed a possible "ODBC driver sent negative string size" error when
   using empty strings or None with output parameters for Sybase ASE
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 * Fixed the handling of None as default value for output parameters
   in e.g. stored procedures to use VARCHAR binding rather than CHAR
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 * Changed cursor.colcount to be determined on-demand rather than
   right after the prepare step of statement execution.

 * Fixed an issue with mxODBC triggering unwanted ODBC errors after
   the prepare step when calling a stored procedure. These were not
   reported, but do show up in the ODBC log.

 * Fixed some minor issues with the package web installer.


For the full set of changes please check the mxODBC change log:

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For the full set of features mxODBC has to offer, please see:

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Re: new() does not return anything, on singletong pattern

Mario Figueiredo wrote:

> It's just a cheap global, since is ubiquitous throughout the entire
> application, does behave like a singleton, and is a bit too expensive
> to create. A full map in the main application takes 3 or 4 seconds to
> instantiate and occupies around 2 Mb of memory.

2MB is not that big.

3-4 seconds to instantiate is a bit worrying, but you should look at
improving the efficiency of loading a map rather than insisting that there
should be only one map instance. Particularly in the map editor, what if
the user wants to copy parts of one map into a second map? I've often
wanted to do that with games. Every other editor, from music editors to
text editors, allows you to have multiple documents open. Why should game
level editors be stuck in the 1980s?

While Map is a singleton, editing multiple maps at once is impossible (or at
least tiresomely difficult).

-- 
Steven

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Re: new() does not return anything, on singletong pattern

Mario Figueiredo wrote:

> On Thu, 12 Mar 2015 16:31:12 +1100, Steven D'Aprano
>  wrote:
> 
>>Mario Figueiredo wrote:
>>
>>
>>If this is supposed to be a singleton, you can't create more instances.
>>The point of a singleton that there is only one instance (or perhaps a
>>small number, two or three say). Why do you need two different ways to
>>create instances if you only have one instance?
>>
> 
> The map is instantiated from the contents of a saved map file on the
> main application.
> 
> A different application, a map editor, needs to also instantiate an
> object of the class Map. But in this case the map needs to either be
> empty (if the user wants to create a new map), or loaded from the
> saved map file (if the user wants to edit an existing map).

An empty map is just a special case of an existing map, one with no features
added.

I would have a loadfile() method which takes a filename on disk, opens the
file and passes the contents (or the open file object) to another method,
load() to do the actual work:

class Map:
def __new__(cls, width, height, fill, treasure=None):
# Include additional args as needed.
map = super().__new__.(cls)
map.width = width
map.height = height
map.fill = fill
map.treasure = treasure
return map

@classmethod
def loadfile(cls, filename):
with open(filename, 'r') as f:
map = cls.load(f)
return map

@classmethod
def load(cls, f):
# validate and parse file contents
# extract width, height, fill, etc.
map = cls(width, height, fill, treasure)
return map

To get an empty map, you pass the load method a file-like object that
contains whatever an empty map data file will contain. That could literally
be an external file, if you so choose, or you could simply read it from a
global constant or even an embedded string/bytes object:

@classmethod
def new(cls):
"""Return a new empty map."""
emptymap = b"blah blah blah width=100 height=100 fill=1"
f = io.StringIO(emptymap)
return cls.load(f)

This, naturally, assumes that your map format is simple enough and small
enough that an empty map can be embedded into your code. If an empty map is
4MB on disk, you probably don't want to do this :-)

Alternatively, set the default arguments to the __new__ constructor to be
whatever values an empty map uses:

def __new__(cls, width=100, height=100, fill=1, treasure=None):
...

and now your "create empty map" command just calls Map() with no arguments.

>>> I added the following method to the class definition, above:
>>> 
>>> @classmethod
>>> def generate(cls, width, height, fill=terrain[6]):
>>> if Map._instance is None:
>>> Map._instance = super(Map, cls).__new__(cls)
>>> else:
>>> raise Exception('Cannot generate an instance of Map.')
>>> 
>>> Map._instance.author = None
>>> Map._instance.name = None
>>
>>Since this method modifies the singleton instance in place, it doesn't
>>generate a new instance. It shouldn't be called generate().
> 
> No sure what you mean. That method either creates a new instance or
> raises an exception. It doesn't modify an instance in-place.

My mistake, I was confused. You're right, if the instance already exists, it
raises an exception.

>>> Map._instance.description = None
>>>  # etc...
>>>  self.cells = [Cell(fill)] * width * height
>>> return Map._instance
>>
>>That's not your actual code, since the indentation is wrong.
> 
>  Map._instance.description = None
>  # etc...
>  self.cells = [Cell(fill)] * width * height
>  return Map._instance

What's "self"? That's a classmethod, it's not usual to have a self local
variable.

-- 
Steven

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EuroPython 2015: Call for proposal dates available

2015-03-12 Thread M.-A. Lemburg

The Program work group (WG) has decided on the dates for the Call for
Proposal (CFP) dates:

Monday, 2015-03-16  Tuesday, 2015-04-14

You will be able to submit your proposals through the EuroPython
website during these 4 weeks.

We have these types of presentations available for submission:

 * Talks: 170 slots available (80x 30min, 85x 45min, 5x 60min)
 * Trainings: 20 slots
 * Posters: 25 slots
 * Help desks: 5 slots

Please note that the exact number of submissions we can accept depends
on schedule and room requirements, so the above numbers are only
estimates. Talk times include time for questions.

The full Call for Proposal with all details will be made available on
Monday, 2015-03-16. We are publishing these dates early because we’ve
been getting a lot of requests for the CFP dates.

Talks/Trainings in Spanish and Basque
-

Since EuroPython is hosted in Bilbao and EuroPython has traditionally
always been very open to the local Python communities, we are also
accepting a number of talks and trainings in Spanish and Basque.

All other talks/trainings should be held in English.

Talk voting
---

As in 2013, we will again have talk voting, which means that attendees
who have already registered will get to see the talk submissions and
can vote on them. The Program WG will also set aside a number of slots
which they will then select based on other criteria to e.g. increase
diversity or give a chance to less mainstream topics.

The schedule will then be announced early in May.


Enjoy,
--
EuroPython 2015 Team
http://www.europython-society.org/
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generator/coroutine terminology

This is more a question about standard terminology/conventions than about 
semantics - of course assuming I understand :-)

Say I have a simple yielding function:

def foo(x):
   yield x+1
   yield x+2

And I have

g = foo(2)

If I look at type, g's type is 'generator' whereas foo is just plain-ol 
'function.'

Whereas in informal usage we say foo is a generator.

So the question:
What should we call foo and what should we call g?

Same applies when foo is a 'coroutine' ie
something having yield used in an rhs and used with '.send' from outside:
What to call foo and what to call foo(x)?
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Re: generator/coroutine terminology

2015-03-12 Thread Chris Angelico

On Fri, Mar 13, 2015 at 12:35 AM, Rustom Mody  wrote:
> If I look at type, g's type is 'generator' whereas foo is just plain-ol 
> 'function.'
>
> Whereas in informal usage we say foo is a generator.
>
> So the question:
> What should we call foo and what should we call g?

g is a generator object; foo is a generator function - a function
which returns generator objects. Usually, calling both of them
"generators" isn't confusing, as there's not often any context in
which they're ambiguous.

ChrisA
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Re: generator/coroutine terminology

2015-03-12 Thread breamoreboy

On Thursday, March 12, 2015 at 1:35:48 PM UTC, Rustom Mody wrote:
> This is more a question about standard terminology/conventions than about 
> semantics - of course assuming I understand :-)
> 
> Say I have a simple yielding function:
> 
> def foo(x):
>yield x+1
>yield x+2
> 
> And I have
> 
> g = foo(2)
> 
> If I look at type, g's type is 'generator' whereas foo is just plain-ol 
> 'function.'
> 
> Whereas in informal usage we say foo is a generator.
> 
> So the question:
> What should we call foo and what should we call g?
> 
> Same applies when foo is a 'coroutine' ie
> something having yield used in an rhs and used with '.send' from outside:
> What to call foo and what to call foo(x)?

Try the glossary https://docs.python.org/3/glossary.html

If this comes out badly please free to shout as I'm on gg :)
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Re: generator/coroutine terminology

Rustom Mody wrote:

> This is more a question about standard terminology/conventions than about
> semantics - of course assuming I understand :-)
> 
> Say I have a simple yielding function:
> 
> def foo(x):
>yield x+1
>yield x+2
> 
> And I have
> 
> g = foo(2)
> 
> If I look at type, g's type is 'generator' whereas foo is just plain-ol
> 'function.'
> 
> Whereas in informal usage we say foo is a generator.

Hopefully it is clear from context what we actually mean. When in doubt, we
should be explicit.

> So the question:
> What should we call foo and what should we call g?

foo is a generator function, i.e. a function which returns a generator. I'd
also allow generator factory, naming it by intent rather than type.

The result of calling foo, namely foo(x), which you have named g, is a
generator object, which is a kind of iterator.

> Same applies when foo is a 'coroutine' ie
> something having yield used in an rhs and used with '.send' from outside:
> What to call foo and what to call foo(x)?

foo is a generator function, and foo(x) is a generator object. In this case
we can call foo(x) by usage rather than type, and call it a coroutine.

-- 
Steven

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Re: generator/coroutine terminology

Guess I should be pleased that I am doing as good as you (and Chris) describe.
For some reason or not I am not...

On Thursday, March 12, 2015 at 9:58:07 PM UTC+5:30, Steven D'Aprano wrote:
> Rustom Mody wrote:
> 
> > This is more a question about standard terminology/conventions than about
> > semantics - of course assuming I understand :-)
> > 
> > Say I have a simple yielding function:
> > 
> > def foo(x):
> >yield x+1
> >yield x+2
> > 
> > And I have
> > 
> > g = foo(2)
> > 
> > If I look at type, g's type is 'generator' whereas foo is just plain-ol
> > 'function.'
> > 
> > Whereas in informal usage we say foo is a generator.
> 
> Hopefully it is clear from context what we actually mean. When in doubt, we
> should be explicit.

There is a very important 'context' where both have to exist together -- 
teaching beginners.

foo's are written to produce g's. g's come from foo-like.

Better naming would help clarify -- your 'factory' is the best Ive seen so far.
But the docs?!?! Hoo Boy My head spins trying to grok this
https://docs.python.org/3/reference/expressions.html#generator-expressions
And thats after being familiar with the origins of the idea in
scheme/simula/CLU etc.

Noobs could be forgiven for doing worse dont you think??

I guess we need
1. A clear ontology of the base concepts (which is a buzzword for nailed-down 
terminology)
2. Some neat pictures would sure help (me!)
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Re: when may sys.executable be empty

2015-03-12 Thread Robin Becker


On 11/03/2015 18:15, Dave Angel wrote:
.


Just speculating, but how about when the main executable is not python at all,
but it uses a DLL or .so file with Python interpreter.


when I run a django wsgi.py using uwsgi sys.executable points at the uwsgi 
executable. To run subprocess etc I have to find the python that's parallel to 
uwsgi (works in a virtualenv at least).

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Robin Becker

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Re: generator/coroutine terminology

2015-03-12 Thread Marko Rauhamaa

Rustom Mody :

> I guess we need
> 1. A clear ontology of the base concepts (which is a buzzword for
> nailed-down terminology)

According to the documentation, a function whose definition contains a
yield statement is a generator:

   Using a yield expression in a function’s body causes that function to
   be a generator.

   https://docs.python.org/3/reference/expressions.html#yield-exp
   ressions>

   generator
  A function which returns an iterator.

   https://docs.python.org/3/glossary.html#term-generator>

Apparently, what we have here is a discrepancy between the documentation
and the CPython implementation.

In a word, it's a bug (somewhere).


Marko
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Re: new() does not return anything, on singletong pattern

On Thu, 12 Mar 2015 22:29:24 +1100, Steven D'Aprano
 wrote:

>
>I would have a loadfile() method which takes a filename on disk, opens the
>file and passes the contents (or the open file object) to another method,
>load() to do the actual work:
>
>
>class Map:
>def __new__(cls, width, height, fill, treasure=None):
># Include additional args as needed.
>map = super().__new__.(cls)
>map.width = width
>map.height = height
>map.fill = fill
>map.treasure = treasure
>return map
>
>@classmethod
>def loadfile(cls, filename):
>with open(filename, 'r') as f:
>map = cls.load(f)
>return map
>
>@classmethod
>def load(cls, f):
># validate and parse file contents
># extract width, height, fill, etc.
>map = cls(width, height, fill, treasure)
>return map
>
>
>To get an empty map, you pass the load method a file-like object that
>contains whatever an empty map data file will contain. That could literally
>be an external file, if you so choose, or you could simply read it from a
>global constant or even an embedded string/bytes object:
>
>@classmethod
>def new(cls):
>"""Return a new empty map."""
>emptymap = b"blah blah blah width=100 height=100 fill=1"
>f = io.StringIO(emptymap)
>return cls.load(f)
>
>
>This, naturally, assumes that your map format is simple enough and small
>enough that an empty map can be embedded into your code. If an empty map is
>4MB on disk, you probably don't want to do this :-)
>
>Alternatively, set the default arguments to the __new__ constructor to be
>whatever values an empty map uses:
>
>def __new__(cls, width=100, height=100, fill=1, treasure=None):
>...
>
>
>and now your "create empty map" command just calls Map() with no arguments.
>

Your solution is excelent!

Leveraging the __new__ method is something I wasn't considering. It
gracefully deals with the absence of __init__, not forcing me to raise
an exception or document the class to warn against its use.

Thanks a bunch.
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Re: new() does not return anything, on singletong pattern

On Thu, 12 Mar 2015 21:41:16 +1300, Gregory Ewing
 wrote:

>Mario Figueiredo wrote:
>> But PyCharm flags the assignment
>> with a warning telling me that generate() does not return anything and
>> the I lose code completion on the mmap variable.
>
>My guess is that there is a syntax error somewhere
>in your code that's confusing the IDE.

It's a PyCharm bug actually. Confirmed here:

https://youtrack.jetbrains.com/issue/PY-11990

(sidenote: I wasn't finding that before. YouTrack search engine really
needs to handle better word contractions. It was only when I was
filling a bug report myself that it came up with that one in the list
of possible related issues.)
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Python3 "pickle" vs. stdin/stdout - unable to get clean byte streams in Python 3

2015-03-12 Thread John Nagle

  I have working code from Python 2 which uses "pickle"
to talk to a subprocess via stdin/stdio.  I'm trying to
make that work in Python 3.

  First, the subprocess Python is invoked with the "-d' option,
so stdin and stdio are supposed to be unbuffered binary streams.
That was enough in Python 2, but it's not enough in Python 3.

The subprocess and its connections are set up with

  proc = subprocess.Popen(launchargs,stdin=subprocess.PIPE,
stdout=subprocess.PIPE, env=env)

  ...
  self.reader = pickle.Unpickler(self.proc.stdout)
  self.writer = pickle.Pickler(self.proc.stdin, 2)

after which I get

  result = self.reader.load()
TypeError: 'str' does not support the buffer interface

That's as far as traceback goes, so I assume this is
disappearing into C code.

OK, I know I need a byte stream.  I tried

  self.reader = pickle.Unpickler(self.proc.stdout.buffer)
  self.writer = pickle.Pickler(self.proc.stdin.buffer, 2)

That's not allowed.  The "stdin" and "stdout" that are
fields of "proc" do not have "buffer".  So I can't do that
in the parent process.  In the child, though, where
stdin and stdout come from "sys", "sys.stdin.buffer" is valid.
That fixes the ""str" does not support the buffer interface
error."  But now I get the pickle error "Ran out of input"
on the process child side.  Probably because there's a
str/bytes incompatibility somewhere.

So how do I get clean binary byte streams between parent
and child process?

John Nagle
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Re: generator/coroutine terminology

2015-03-12 Thread Terry Reedy


On 3/12/2015 9:35 AM, Rustom Mody wrote:

This is more a question about standard terminology/conventions than about 
semantics - of course assuming I understand :-)

Say I have a simple yielding function:

def foo(x):
yield x+1
yield x+2


This is a generator function


And I have

g = foo(2)

If I look at type, g's type is 'generator' whereas foo is just plain-ol 
'function.'

Whereas in informal usage we say foo is a generator.


I do not, because it does cause confusion, in spite of denials by people 
who use 'generator' ambiguously.


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Re: new() does not return anything, on singletong pattern

On Thu, 12 Mar 2015 22:04:30 +1100, Steven D'Aprano
 wrote:

>
>3-4 seconds to instantiate is a bit worrying, but you should look at
>improving the efficiency of loading a map rather than insisting that there
>should be only one map instance. Particularly in the map editor, what if
>the user wants to copy parts of one map into a second map? I've often
>wanted to do that with games. Every other editor, from music editors to
>text editors, allows you to have multiple documents open. Why should game
>level editors be stuck in the 1980s?
>
>While Map is a singleton, editing multiple maps at once is impossible (or at
>least tiresomely difficult).

Those scnearios don't apply here. And the map editor isn't even a
first-class application in the system. Just a patch to corrupt map
files that will thus stand a chance to be recovered. I can understand
your resistance to the idea of yet another singleton being born to
this world. I myself despise the pattern. I think the GoF were drunk
by the time they reached the Singleton. The whole Creational Patterns
section was really only going downhill, anyways. Starts strong and
ends up with the justin bieber of patterns.

And I'm not using it because of some ulterior design principle. I
don't plan to justify it because I have a *real* reason to use a
singleton. I don't. I'm just using it because it is really
accomodating for me to have this global without having to trace it
around function calls arguments. That's evil. I suppose I could just
make it really global. But to me that's even more evil and I can't
consider it.

Of course. What is a singleton today can't be twins tomorrow, triplets
the day after and a crowd the next. I realize this. But... yeah... I'm
a sinner. Besides it's not that I never had to revisit my code before
because of Best Practices (tm).

In truth the road to damnation starts when we decide to write our
first line of code.
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Re: generator/coroutine terminology

2015-03-12 Thread Marko Rauhamaa

Terry Reedy :

> On 3/12/2015 9:35 AM, Rustom Mody wrote:
>> This is more a question about standard terminology/conventions than
>> about semantics - of course assuming I understand :-)
>>
>> Say I have a simple yielding function:
>>
>> def foo(x):
>> yield x+1
>> yield x+2
>
> This is a generator function

Which in the official language specification is an elaborate synonym of
a generator.


Marko
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PSF news - BBC launches MicroBit

2015-03-12 Thread Mark Lawrence

http://pyfound.blogspot.co.uk/2015/03/bbc-launches-microbit.html may be 
of interest to some of you.


--
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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My emails are getting bounced?

2015-03-12 Thread Ryan Gonzalez

I'm posting this here because I have no clue who the heck the mailing list
manager is.

I got this message:

Your membership in the mailing list Python-ideas has been disabled due
to excessive bounces The last bounce received from you was dated
12-Mar-2015.  You will not get any more messages from this list until
you re-enable your membership.  You will receive 3 more reminders like
this before your membership in the list is deleted.

A quick Google shows:

Find out why list mail to you is bouncing and correct the problem. You
may be able to see a returned bounce by setting
bounce_notify_owner_on_disable to Yes. This will cause Mailman to send
the triggering bounce to the owner, but since that's you, it may
bounce too.

Is it possible for someone to set this up for my email on Python-ideas?

Again, not sure who the manager is, so I'm sending this here.

-- 
Ryan
[ERROR]: Your autotools build scripts are 200 lines longer than your
program. Something’s wrong.
http://kirbyfan64.github.io/
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Re: Python3 "pickle" vs. stdin/stdout - unable to get clean byte streams in Python 3

2015-03-12 Thread Cameron Simpson


On 12Mar2015 12:55, John Nagle  wrote:

 I have working code from Python 2 which uses "pickle"
to talk to a subprocess via stdin/stdio.  I'm trying to
make that work in Python 3.
 First, the subprocess Python is invoked with the "-d' option,
so stdin and stdio are supposed to be unbuffered binary streams.


You shouldn't need to use unbuffered streams specificly. It should be enough to 
.flush() the output stream (at whichever end) after you have written the pickle 
data.


I'm skipping some of your discussion; I can see nothing wong. I don't use 
pickle itself so aside from saying that your use seems to conform to the python 
3 doco I can't comment more deeply. That said, I do use subprocess a fair bit.


[...]

 result = self.reader.load()
TypeError: 'str' does not support the buffer interface
That's as far as traceback goes, so I assume this is
disappearing into C code.


No line numbers at all? Or, I suppose, just the line number from your program 
and nothing from the pickle module?



OK, I know I need a byte stream.  I tried
 self.reader = pickle.Unpickler(self.proc.stdout.buffer)
 self.writer = pickle.Pickler(self.proc.stdin.buffer, 2)


You should not need to care about these. They're not required.


That's not allowed.  The "stdin" and "stdout" that are
fields of "proc" do not have "buffer".  So I can't do that
in the parent process.  In the child, though, where
stdin and stdout come from "sys", "sys.stdin.buffer" is valid.


But irrelevant. Besides, the stream buffer may not contain the whole pickle 
data anyway; it will be empty before a read and quite possibly incomplete 
afterwards. It is just a buffer.



That fixes the ""str" does not support the buffer interface
error."


I'm not sure "fix" is the right characterisation here.


But now I get the pickle error "Ran out of input"
on the process child side.  Probably because there's a
str/bytes incompatibility somewhere.


No, probably because the buffer is only ever a snapshot of part of the stream.

str/bytes errors are more glaringly obviously so.


So how do I get clean binary byte streams between parent
and child process?


This is where I'm confused: my experience is that Popen.subprocess gives you 
binary streams; I always need to put an encoder/decoder on them to use text.  
Did that just the other day.


BTW, this is on some UNIX variant? Should not be very relevant...

Further questions:

What does self.proc.stdout.__class__ say? And for stdin?

Cheers,
Cameron Simpson 

My opinions are borrowed from someone who no longer needs them.
   -- katma...@uga.cc.uga.edu
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Re: Python3 "pickle" vs. stdin/stdout - unable to get clean byte streams in Python 3

2015-03-12 Thread Peter Otten

John Nagle wrote:

>   I have working code from Python 2 which uses "pickle"
> to talk to a subprocess via stdin/stdio.  I'm trying to
> make that work in Python 3.
> 
>   First, the subprocess Python is invoked with the "-d' option,
> so stdin and stdio are supposed to be unbuffered binary streams.
> That was enough in Python 2, but it's not enough in Python 3.
> 
> The subprocess and its connections are set up with
> 
>   proc = subprocess.Popen(launchargs,stdin=subprocess.PIPE,
> stdout=subprocess.PIPE, env=env)
> 
>   ...
>   self.reader = pickle.Unpickler(self.proc.stdout)
>   self.writer = pickle.Pickler(self.proc.stdin, 2)
> 
> after which I get
> 
>   result = self.reader.load()
> TypeError: 'str' does not support the buffer interface
> 
> That's as far as traceback goes, so I assume this is
> disappearing into C code.
> 
> OK, I know I need a byte stream.  I tried
> 
>   self.reader = pickle.Unpickler(self.proc.stdout.buffer)
>   self.writer = pickle.Pickler(self.proc.stdin.buffer, 2)
> 
> That's not allowed.  The "stdin" and "stdout" that are
> fields of "proc" do not have "buffer".  So I can't do that
> in the parent process.  In the child, though, where
> stdin and stdout come from "sys", "sys.stdin.buffer" is valid.
> That fixes the ""str" does not support the buffer interface
> error."  But now I get the pickle error "Ran out of input"
> on the process child side.  Probably because there's a
> str/bytes incompatibility somewhere.
> 
> So how do I get clean binary byte streams between parent
> and child process?

I don't know what you have to do to rule out deadlocks when you use pipes 
for both stdin and stdout, but binary streams are the default for 
subprocess. Can you provide a complete example?

Anyway, here is a demo for two-way communication using the communicate() 
method:

$ cat parent.py
import pickle
import subprocess

data = (5, 4.3, "üblich ähnlich nötig")

p = subprocess.Popen(
["python3", "child.py"],
stdin=subprocess.PIPE,
stdout=subprocess.PIPE)

result = p.communicate(pickle.dumps(data, protocol=2))[0]
print(pickle.loads(result))

$ cat child.py
import sys
import pickle

a, b, c = pickle.load(sys.stdin.buffer)
pickle.dump((a, b, c.upper()), sys.stdout.buffer)

$ python3 parent.py 
(5, 4.3, 'ÜBLICH ÄHNLICH NÖTIG')

This is likely not what you want because here everything is buffered so that 
continuous interaction is not possible.

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Re: My emails are getting bounced?

2015-03-12 Thread Tim Golden


On 12/03/2015 21:56, Ryan Gonzalez wrote:

I'm posting this here because I have no clue who the heck the mailing
list manager is.


If you look at the bottom of this page:

https://mail.python.org/mailman/listinfo/python-ideas

you can see the list maintainers which is also a mailto: link which will 
reach them all. Hopefully they can look at the setup for your user over 
there.


TJG
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Re: My emails are getting bounced?

2015-03-12 Thread Chris Angelico

On Fri, Mar 13, 2015 at 8:56 AM, Ryan Gonzalez  wrote:
>
> Your membership in the mailing list Python-ideas has been disabled due
> to excessive bounces The last bounce received from you was dated
> 12-Mar-2015.  You will not get any more messages from this list until
> you re-enable your membership.  You will receive 3 more reminders like
> this before your membership in the list is deleted.

I also got this notification, and in the past, it's been because Gmail
mishandles spam - bouncing it instead of either accepting or
discarding it. The post gets handed between Gmail and Mailman until
one of them gives up, and in this case, it's Mailman. It may be that
that's what happened again. (Irony would be if the post originated
from Google Groups, which would mean it got past the Google spam
filter on one side, but tripped the filter on the other side.)

ChrisA
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Re: My emails are getting bounced?

2015-03-12 Thread rymg19

On Thursday, March 12, 2015 at 5:01:46 PM UTC-5, Tim Golden wrote:
> On 12/03/2015 21:56, Ryan Gonzalez wrote:
> > I'm posting this here because I have no clue who the heck the mailing
> > list manager is.
> 
> If you look at the bottom of this page:
> 
> https://mail.python.org/mailman/listinfo/python-ideas
> 
> you can see the list maintainers which is also a mailto: link which will 
> reach them all. Hopefully they can look at the setup for your user over 
> there.
> 
> TJG

Ok; I'm emailing now.

I didn't even get this message. I had to go to the Google Groups interface to 
check for replies.
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Google Code Shutting Down

2015-03-12 Thread Josh English

I've been hosting Python projects on Google Code, and they're shutting down.

Damn.

What is the recommended replacement for Code Hosting that works reliably with 
PyPi and pip?
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Re: My emails are getting bounced?

2015-03-12 Thread rymg19

On Thursday, March 12, 2015 at 5:09:16 PM UTC-5, Chris Angelico wrote:
> On Fri, Mar 13, 2015 at 8:56 AM, Ryan Gonzalez  wrote:
> >
> > Your membership in the mailing list Python-ideas has been disabled due
> > to excessive bounces The last bounce received from you was dated
> > 12-Mar-2015.  You will not get any more messages from this list until
> > you re-enable your membership.  You will receive 3 more reminders like
> > this before your membership in the list is deleted.
> 
> I also got this notification, and in the past, it's been because Gmail
> mishandles spam - bouncing it instead of either accepting or
> discarding it. The post gets handed between Gmail and Mailman until
> one of them gives up, and in this case, it's Mailman. It may be that
> that's what happened again. (Irony would be if the post originated
> from Google Groups, which would mean it got past the Google spam
> filter on one side, but tripped the filter on the other side.)
> 
> ChrisA

Ugh. I love Gmail, but this sucks.
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Re: Google Code Shutting Down

On Thu, 12 Mar 2015 15:26:08 -0700 (PDT), Josh English
 wrote:

>I've been hosting Python projects on Google Code, and they're shutting down.
>
>Damn.
>
>What is the recommended replacement for Code Hosting that works reliably with 
>PyPi and pip?

Essentially anywhere where either Git, Bazaar, Mercurial or Subversion
are supported. See:

https://pip.pypa.io/en/latest/reference/pip_install.html#vcs-support
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Re: Python3 "pickle" vs. stdin/stdout - unable to get clean byte streams in Python 3

2015-03-12 Thread John Nagle

On 3/12/2015 2:56 PM, Cameron Simpson wrote:
> On 12Mar2015 12:55, John Nagle  wrote:
>> I have working code from Python 2 which uses "pickle" to talk to a
>> subprocess via stdin/stdio.  I'm trying to make that work in Python
>> 3. First, the subprocess Python is invoked with the "-d' option, so
>> stdin and stdio are supposed to be unbuffered binary streams.
> 
> You shouldn't need to use unbuffered streams specifically. It should
> be enough to .flush() the output stream (at whichever end) after you
> have written the pickle data.

Doing that.

It's a repeat-transaction thing.  Main process sends pickeled
item to subprocess, subprocess reads item, subprocess does work,
subprocess writes picked item to parent.  This repeats.

I call writer.clear_memo() and set reader.memo = {} at the
end of each cycle, to clear Pickle's cache.  That all worked
fine in Python 2.  Are there any known problems with reusing
Python 3 "pickle"s streams?

The identical code works with Python 2.7.9; it's converted to Python
3 using "six" so I can run on both Python versions and look for
differences.  I'm using Pickle format 2, for compatibility.
(Tried 0, the ASCII format; it didn't help.)

> I'm skipping some of your discussion; I can see nothing wrong. I
> don't use pickle itself so aside from saying that your use seems to
> conform to the python 3 docs I can't comment more deeply. That said,
> I do use subprocess a fair bit.

 I'll have to put in more logging and see exactly what's going
over the pipes.

John Nagle

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Re: My emails are getting bounced?

2015-03-12 Thread Skip Montanaro

On Thu, Mar 12, 2015 at 4:56 PM, Ryan Gonzalez  wrote:

> Your membership in the mailing list Python-ideas has been disabled due
> to excessive bounces


I got the same treatment. Probably a mail loop involving Gmail.

Skip
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Code hosting providers (was: Google Code Shutting Down)

2015-03-12 Thread Ben Finney

Mario Figueiredo  writes:

> On Thu, 12 Mar 2015 15:26:08 -0700 (PDT), Josh English
>  wrote:
>
> > What is the recommended replacement for Code Hosting that works
> > reliably with PyPi and pip?
>
> Essentially anywhere where either Git, Bazaar, Mercurial or Subversion
> are supported.

Installing directly from whatever the latest revision in VCS, is not a
good replacement. What's needed is a VCS hosting provider that also
expects you to publish tarballs at specific versions.

For that, you want to choose a provider that runs entirely free software
for the service – not just the VCS, but whatever other features you use
need to be freely available for someone to run another instance of the
same service.

Otherwise you're stuck any time you want to migrate your project, which
is what led to this thread in the first place.

This is called “vendor lock-in”: services like GitHub and Google Code
lock you in to the one provider, because if you want to migrate you
can't take your project data (not just VCS but also issues, merge
requests, etc.) with you to continue somewhere else.

Any service which doesn't run their service on free software is one to
avoid http://mako.cc/writing/hill-free_tools.html>; free software
projects need free tools to remain that way.

GitLab https://about.gitlab.com/> is a good option: they provide
VCS, file hosting, wiki, issue tracker, code review via merge requests,
etc. and all of it can be migrated to any other instance of the same
service.

Also worth watching is Kallithea, a new federated code hosting service
https://kallithea-scm.org/>. It supports Mercurial and Git for VCS,
code review, and integrates with existing issue trackers. Because it's
federated, you won't suffer from vendor lock-in.

Good hunting in finding a free-software code hosting provider for your
projects!

-- 
 \  “I knew things were changing when my Fraternity Brothers threw |
  `\   a guy out of the house for mocking me because I'm gay.” |
_o__)  —postsecret.com, 2010-01-19 |
Ben Finney

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Re: generator/coroutine terminology

On Thursday, March 12, 2015 at 11:25:32 PM UTC+5:30, Marko Rauhamaa wrote:
> Rustom Mody :
> 
> > I guess we need
> > 1. A clear ontology of the base concepts (which is a buzzword for
> > nailed-down terminology)
> 
> According to the documentation, a function whose definition contains a
> yield statement is a generator:
> 
>Using a yield expression in a function's body causes that function to
>be a generator.
> 
>https://docs.python.org/3/reference/expressions.html#yield-exp
>ressions>
> 
>generator
>   A function which returns an iterator.
> 
>https://docs.python.org/3/glossary.html#term-generator>
> 
> Apparently, what we have here is a discrepancy between the documentation
> and the CPython implementation.
> 
> In a word, it's a bug (somewhere).

Throwing out some thought for better terminology.
[Yeah needs to be chewed on a bit...]

With respect to my example above:

def foo(x):
   yield x+1
   yield x+2


g = foo(2) 

Generator-instance: g
Generator-factory: foo
Generator: Concept in python (ontology) elaborated in terms of the above

Situation with coroutines is worse
[Or I cant think of good terms...]
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Re: My emails are getting bounced?

rym...@gmail.com wrote:

> I didn't even get this message. I had to go to the Google Groups interface
> to check for replies.

Have you checked your junk mail folder?

Unfortunately, the three of the Big Four mail providers -- Yahoo, Gmail, and
AOL[1] -- have collectively decided that mailing lists are oh-so-2012 and
are putting in place policies which make it harder and harder for their
users to successfully subscribe and post to mailing lists. Ironically,
Hotmail is probably the best of the Big Four in this regard.

I don't even think it is a conscious decision that mailing lists are
obsolete, I think it's mostly just technical incompetence and malice.
Apparently Yahoo and AOL got hacked a few years ago, the bad guys managed
to send out masses of spam via their mail servers, and they panicked,
over-reacted (or at least badly reacted) and implemented a half-arsed,
badly thought out implementation of DMARC which effectively makes it all
but impossible for Yahoo/AOL users to use mailing lists. I've been told
that Yahoo basically treats all bulk email as spam unless it comes from
Yahoo itself.

And of course Gmail and Google Groups make it hard to interoperate with the
rest of Usenet and non-Google mailing lists. They don't have the excuse of
technical incompetence. It's ironic that as Microsoft has slowly but surely
(and kicking and screaming most of the way) become a better web citizen,
Google's motto "Don't Be Evil" has become a sad joke more often than not.

[1] Hard to believe, but yes people do still use AOL.

-- 
Steven

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Re: Code hosting providers (was: Google Code Shutting Down)

Ben Finney wrote:

> Also worth watching is Kallithea, a new federated code hosting service
> https://kallithea-scm.org/>. It supports Mercurial and Git for VCS,
> code review, and integrates with existing issue trackers. Because it's
> federated, you won't suffer from vendor lock-in.


What do you mean by "federated"?


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Steven

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Re: Code hosting providers

2015-03-12 Thread Michael Torrie

On 03/12/2015 09:17 PM, Steven D'Aprano wrote:
> Ben Finney wrote:
>> Also worth watching is Kallithea, a new federated code hosting service
>> https://kallithea-scm.org/>. It supports Mercurial and Git for VCS,
>> code review, and integrates with existing issue trackers. Because it's
>> federated, you won't suffer from vendor lock-in.
> 
> What do you mean by "federated"?

I think it's a fancy way of saying you can run your own instance of the
full web system on your own server under your own domain name.

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KB 2670838 - The EVIL UPDATE

2015-03-12 Thread Skybuck Flying

KB 2670838 - The EVIL UPDATE

This Windows 7 update wasted a lot of my time today.

I could not find my own postings in the past... maybe I was unsure in the
past... I am still unsure today.. but much more sure than previously.

When installing IE11 I suspect this patch also gets installed.

This patch will cause:

1. Windows Live Mail fail to crash, making mail inaccessible.
2. Company of Heroes, Tales of Valor to crash.
3. Call of Duty 5 World at War to stop loading.
4. Possibly even IE9 to keep crashing...
5. And perhaps other misschief.

This patch is the worst patch I have ever seen... I am not 100% sure but
it's a very good guess.

Therefore it's time for me to spam this message all across usenet... so that
I will always find it in google hopefully, next time it pops it's ugly
head...

Hopefully it will save my lost of time in the future.

Also bare in mind:

IE9 crashes
IE10,IE11 is junk, it's slow... it's laggy and it's not worth this patch
trouble.

My advice is stick with Firefox and other browsers... always make sure to
have multiple browsers installed otherwise you might be stranded...

Also if you ever have a crashing internet explorer and you really can't
recover... remember that you can de-install it... this will revert it back
to IE8... at least that should give you a chance to become "unstranded" and
access the web again for help.

KB 2670838 - The EVIL UPDATE

http://answers.microsoft.com/en-us/windows/forum/windows_7-windows_update/kb-2670838-the-evil-update/08bfdb2b-6896-4c34-89c2-16896a25dc3d

I was hoping Microsoft fixed this patch by now... unfortunately they did
not... and are probably too busy messing around with windows 8.1/windows 10
etc.

Shame on them cause this is ONE BITCH OF A PATCH !!!

Also FUCK Microsoft for intentionally DAMAGING computer software !

My trust in Microsoft is disappearing.

Their behaviour is always the same basically:

"Damage old software to try and get people to buy new systems/upgrade".

This patch makes me sick to my stomach... mostly because it endangers my
data !

If Microsoft causes my DATA to be lost or inaccessable their software will
be TERMINATED by me and I will switch to something else.

Even if it's just a stupid little patch like this... this kind of thing
making my mail archieve inaccessible is unacceptable behaviour.

I will keep a close eye on this patch to see if it ever gets fixed.

If now I may get so sick to my stumach that I might just skip Windows 10 and
go to Linux route...

For now at least it can be deinstalled... but it comes at a great risk: no
more internet explorer, no more internet explorer updates...

Now I have to trust Mozilla and Open Source developers ?!

What's the world coming too ?! ;) ;) ;)

If Microsoft keeps this up they will drive everybody to open source... is
that what you want Microsoft ?

You guys are doing really bad right now... one little patch and you can't
fix it REally ???

I will examine your details about this patch... I probably did it n the past
already...

You know what I will do it right now... just to see if I can add some info
to this posting.

Basically this is some kind of graphics patch update for hybrid graphics
cards... fuck that... please shove this up your ass.

Integrated graphics probably

HHH

WHERE HAVE I HEAR THAT BEFORE

DOES INTEL WRING A BE ?

INTEGRATED ELECTRONICS = INTEL.

This patch is apperently CODE-AUTHORED BY INTEL.

INTEL IS PURPOSELY NUKING YOUR SYSTEMS.

THIS PUTS A NEW PERSPECTIVE ON INTEL.

I WAS PLANNING TO BUY THEIR NEW SKYLAKE PROCESSOR...

THOUGH THEIR HASWELL HAD A TRANSACTIONAL MEMORY BUG.

THIS LATEST RELEVATION/CONCLUSION SHEDS NEW LIGHT ON THIS POTENTIAL EVIL
FROM INTEL.

I can only advice researchers, academics, hackers, press... to investigate
this matter further.

IF THIS IS TRUE THEN THIS IS A GIGANTIC SCHANDAL OF IMAGINABLE PROPORTIONS
AND NEEDS A SEVERE COUNTER REACTION.

IF THIS IS TRUE I CAN RECOMMEND A BOYCOTT OF INTEL PROCESSORS AND MICROSOFT
SOFTWARE AND SWITCH TO OPEN SOURCE SOFTWARE where these kind of trust issues
and bugs can be more easily spotted and fixed and hopefully AVOIDED.

Basically I DEMAND A FULL INVESTIGATION from the goverments INTO PATCH
2670838.

GOODBYE,
FAILURE TO DO SO PUTS YOUR SYSTEMS AT RISK !

Bye,
Skybuck.

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Re: generator/coroutine terminology

Rustom Mody wrote:

> On Thursday, March 12, 2015 at 11:25:32 PM UTC+5:30, Marko Rauhamaa wrote:
>> Rustom Mody :
>> 
>> > I guess we need
>> > 1. A clear ontology of the base concepts (which is a buzzword for
>> > nailed-down terminology)
>> 
>> According to the documentation, a function whose definition contains a
>> yield statement is a generator:
>> 
>>Using a yield expression in a function's body causes that function to
>>be a generator.
>> 
>>https://docs.python.org/3/reference/expressions.html#yield-exp
>>ressions>
>> 
>>generator
>>   A function which returns an iterator.
>> 
>>https://docs.python.org/3/glossary.html#term-generator>
>> 
>> Apparently, what we have here is a discrepancy between the documentation
>> and the CPython implementation.
>> 
>> In a word, it's a bug (somewhere).
> 
> Throwing out some thought for better terminology.
> [Yeah needs to be chewed on a bit...]
> 
> With respect to my example above:
> 
> def foo(x):
>yield x+1
>yield x+2
> 
> 
> g = foo(2)
> 
> Generator-instance: g
> Generator-factory: foo
> Generator: Concept in python (ontology) elaborated in terms of the above

I think that is is reasonable. I would include "generator function" as a
synonym for generator factory. (Factories are more inclusive than
functions -- a factory could include a class with a "make_generator"
method, for example.)

Where the distinction is clear, or not important, than calling both g and
foo "generators" is acceptable shorthand. I realise that can be confusing
to beginners, but jargon often is confusing to beginners until they have
learned enough to be able to correctly interpret things in context.

> Situation with coroutines is worse
> [Or I cant think of good terms...]

Not really. The difference between a coroutine and a generator is mostly in
usage, that is, intent. They both use the same type, they both have send
methods, they both are generated the same way. If you are foolish, you can
even mix generator-behaviour and coroutine-behaviour in the same function:

py> def g():
... yield 1
... yield 2
... x = yield 3
... yield x + 1000
...
py> a = g()
py> next(a)
1
py> next(a)
2
py> next(a)
3
py> a.send(99)
1099

But don't do that.

So as far as Python is concerned, a coroutine is just a generator instance
which you use in a particular way, not a different kind of object. So I
would use similar terminology:

A generator function/factory returns a generator instance, which we use as a
coroutine, so we can call it a coroutine.

-- 
Steven

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Re: Code hosting providers

2015-03-12 Thread Ben Finney

Steven D'Aprano  writes:

> Ben Finney wrote:
>
> > Also worth watching is Kallithea, a new federated code hosting service
> > https://kallithea-scm.org/>. It supports Mercurial and Git for VCS,
> > code review, and integrates with existing issue trackers. Because it's
> > federated, you won't suffer from vendor lock-in.
>
> What do you mean by "federated"?

A service is federated if an independent, perhaps even competing, vendor
can provide the same service and all users of the service participate,
moving freely from one vendor to another as they choose without losing
any of their data or identity.

Another term is “decentralised”, though that says only what the service
is not. I prefer the term “federated” because it describes what the
service *is*: composed of multiple parties, collaborating on equal terms
enforced for the protection of the people participating in the service.

If a service's features use proprietary protocols or undisclosed APIs or
in any other way make it infeasible for a user joining today to reliably
migrate their accumulated data to a different vendor at some future
time, then that service is not federated and its users are vulnerable to
vendor lock-in.

The email system, for example, is federated: my 
data can reliably (and has, several times) survive migration to any
vendor who provides standard email service, because I lose no access to
any of my history or identity or accumulated data or access or ongoing
functionality with the same data. By “reliably” I mean that I can move
it all from one vendor to another, and even back again if I choose, in
the knowledge that the standard POP, IMAPv4, and SMTP protocols will be
honoured, because to fail in that would be a bug severe enough that the
vendor would be avoided as not providing the service.

Other examples of federated systems include:

* Avatar image serving: Libravatar https://www.libravatar.org/>.

* Social networking: Diaspora https://joindiaspora.com/>.

* Version control: Git http://git-scm.com/>.

* The World Wide Web, and the internet as originally designed

http://www.theguardian.com/technology/2012/sep/05/tim-berners-lee-internet-off-switch>.

To the extent that vendor lock-in is possible, the service is not
federated. Corollary: some features of a vendor's offerings can be
federated, and others not; and to talk of the vendor's complete set of
offerings as “federated” can only be true if they all are.

The GitHub service, for example, is not federated, because while mere
Git repositories *are* federated, significant GitHub features (issue
tracker, pull requests, and other important history and project data)
cannot reliably be migrated smoothly to another instance provided by a
competing vendor.

Ned Batchelder and Nick Coghlan have written insightfully on this
http://nedbatchelder.com/blog/201405/github_monoculture.html>
https://mail.python.org/pipermail/python-dev/2014-November/137153.html>
with regard to why GitHub – or any non-federated service – is not a good
option for projects that intend to stay viable.

It will be good to see Kallithea https://kallithea-scm.org/> come
into its own; until then we have GitLab https://about.gitlab.com/>
and Redmine https://www.redmine.org/> and even the juggernaut of
Launchpad https://launchpad.net/>; they are all federated and avoid
vendor lock-in.

We should ask hard questions to projects that choose to host their
irreplaceable data – not just VCS but issues, user identities,
discussions, documentation, etc. – on services that they can't reliably
migrate from. They are demonstrating they don't intend to be around for
long; why should we invest any effort in them?

-- 
 \  “The most common way people give up their power is by thinking |
  `\   they don't have any.” —Alice Walker |
_o__)  |
Ben Finney

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Re: Code hosting providers

2015-03-12 Thread Ben Finney

Michael Torrie  writes:

> On 03/12/2015 09:17 PM, Steven D'Aprano wrote:
> > What do you mean by "federated"?
>
> I think it's a fancy way of saying you can run your own instance of the
> full web system on your own server under your own domain name.

With the corollary that *any* vendor motivated to do so can serve the
same function. Meaning the options aren't just “use this vendor or get
nothing”, as they are with a centralised service.

With a federated service, anyone *can* run their own instance, which
means that few people have to: vendors can pop up and compete with one
another, participants have the option of moving to a different vendor
taking their data and functionality and established relationships and
discussions and identity where they choose.

-- 
 \ “The aim of science is not to open the door to infinite wisdom, |
  `\but to set some limit on infinite error.” —Bertolt Brecht, |
_o__)_Leben des Galilei_, 1938 |
Ben Finney

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Re: Google Code Shutting Down

2015-03-12 Thread Ian Kelly

On Thu, Mar 12, 2015 at 4:26 PM, Josh English
 wrote:
> I've been hosting Python projects on Google Code, and they're shutting down.
>
> Damn.
>
> What is the recommended replacement for Code Hosting that works reliably with 
> PyPi and pip?

Google has been migrating most of its own open source projects to GitHub.
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Re: Code hosting providers

2015-03-12 Thread Paul Rubin

Ben Finney  writes:
> Any service which doesn't run their service on free software is one to
> avoid http://mako.cc/writing/hill-free_tools.html>; free software
> projects need free tools to remain that way.
>
> GitLab https://about.gitlab.com/> is a good option: they provide
> VCS, file hosting, wiki, issue tracker, code review via merge requests...
> Also worth watching is Kallithea, a new federated code hosting service
> https://kallithea-scm.org/>. It supports Mercurial and Git for VCS,
> code review, and integrates with existing issue trackers. Because it's
> federated, you won't suffer from vendor lock-in.

Thanks for that informative post: I've been uncomfortable with the reach
of Github and you've done a good job explaining the reasons.

I personally use self-hosted git repositories on cheap VPS servers which
is easy to do, but doesn't supply issue tracking.  I know various
projects that use either Trac or Bugzilla but I haven't tried operating
those.

One interesting and very lightweight alternative is Fossil, which is an
all-in-one program that does lots of the same stuff as Git, Trac, a web
server, and a wiki, all rolled into a single C program that uses about 1
meg of ram.  It's written by the guy who wrote SQLite and it in fact
uses SQLite as the underlying data store.  It has a philosophical
difference with git in that it's difficult to "rewrite history" which
some workflows expect you to do.  I've sometimes wondered how difficult
it would be to modify Fossil to support that feature.
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Re: generator/coroutine terminology