Re: Why exception from os.path.exists()?

2018-06-10 Thread Charles Hixson
On 06/07/2018 12:45 AM, Chris Angelico wrote: On Thu, Jun 7, 2018 at 1:55 PM, Steven D'Aprano wrote: On Tue, 05 Jun 2018 23:27:16 +1000, Chris Angelico wrote: And an ASCIIZ string cannot contain a byte value of zero. The parallel is exact. Why should we, as Python programmers, care one whit

possible bug in while loop test

2017-09-02 Thread Charles Hixson
python3 --version Python 3.5.3 Running on Debian stretch In this code s is a string parameter while (j < k and \ (s[j].isalnum()) or \ (s[j] in seps and s[j+1].isalnum()) ): j = j + 1 print ("i = {0}, j = {1}, k = {2}, len[s] = {3}". \ format(i,

Re: Multiprocessing queues receiving from wrong process

2016-12-23 Thread Charles Hixson
On 12/23/2016 01:56 PM, Charles Hixson wrote: I was looking to avoid using a upd connection to transfer messages between processes, so I thought I'd use multiprocessing (which I expect would be faster), but...I sure would appreciate an explanation of this problem. When I run the

Multiprocessing queues receiving from wrong process

2016-12-23 Thread Charles Hixson
I was looking to avoid using a upd connection to transfer messages between processes, so I thought I'd use multiprocessing (which I expect would be faster), but...I sure would appreciate an explanation of this problem. When I run the code (below) instead of messages receiving messages from th

Multiprocessing interactive processes with connections

2016-09-06 Thread nospam . Charles Hixson
I want to process a bunch of processes that all talk to each other. I've figured out how to do this using queues with the main process as the mail handler, but I'd rather have them talk directly. If I use connections, then I can pass the pipes to the processes, but there doesn't seem to be anythin

Multiprocessing interactive processes with connections

2016-09-06 Thread Charles Hixson
I want to process a bunch of processes that all talk to each other. I've figured out how to do this using queues with the main process as the mail handler, but I'd rather have them talk directly. If I use connections, then I can pass the pipes to the processes, but there doesn't seem to be an

asyncio, coroutines, etc. and simultaneous execution

2015-08-23 Thread Charles Hixson
If I understand correctly asyncio, coroutines, etc. (and, of course, Threads) are not simultaneously executed, and that if one wants that one must still use multiprocessing. But I'm not sure. The note is still there at the start of threading, so I'm pretty sure about that one. The requiremen

Re: __next__ and StopIteration

2015-02-09 Thread Charles Hixson
On 02/09/2015 08:46 PM, Chris Angelico wrote: On Tue, Feb 10, 2015 at 3:33 PM, Charles Hixson wrote: The proper version of the "hard way" is: 1) The __iter__ method of the iterable constructs a new iterator instance and returns it. 2) The __iter__ method of the *iterator* simp

Re: __next__ and StopIteration

2015-02-09 Thread Charles Hixson
On 02/09/2015 03:56 PM, Ian Kelly wrote: On Mon, Feb 9, 2015 at 4:30 PM, Steven D'Aprano wrote: The way you write iterators is like this: Method 1 (the hard way): - Give your class an __iter__ method which simply returns self: def __iter__(self): return self - Give your clas

__next__ and StopIteration

2015-02-09 Thread Charles Hixson
I'm trying to write a correct iteration over a doubly indexed container, and what I've got so far is:def __next__ (self): for rowinrange(self._rows): for col in range(self._cols): if self._grid[row][col]: yieldself._grid[row]

Re: Multiprocessing process termination

2014-12-31 Thread Charles Hixson
On 12/31/2014 01:18 PM, MRAB wrote: On 2014-12-31 19:33, Charles Hixson wrote: In order to allow multiple processes to access a database (currently SQLite) I want to run the process in a separate thread. Because it will be accessed from multiple processes I intent to use Queues for shifting

Multiprocessing process termination

2014-12-31 Thread Charles Hixson
In order to allow multiple processes to access a database (currently SQLite) I want to run the process in a separate thread. Because it will be accessed from multiple processes I intent to use Queues for shifting messages back and forth. But none of the individuals processes will know when al

multiprocessing vs. asyncio.SubprocessProtocol

2014-07-31 Thread Charles Hixson
What are the tradeoffs between using multiprocessing vs. using asyncio.SubprocessProtocol? This only one that I've noticed is that asyncio seems to require much more hands-on management of message queueing. OTOH, I'm no expert in either of them, and I might be missing something that will bite m

multiprocessing problem: queue.get() not finding pushed values

2014-07-15 Thread Charles Hixson
I don't think I can reduce it much beyond this. I'm trying to run Sqlite in a separate process, but I'm running into problems. *The code:* from collectionsimportnamedtuple from multiprocessing import Process, Queue, current_process from queue import Empty, Full Msg=namedtuple (

Re: Proper deletion of selected items during map iteration in for loop: Thanks to all

2014-04-26 Thread Charles Hixson
On 04/25/2014 10:53 AM, Charles Hixson wrote: What is the proper way to delete selected items during iteration of a map? What I want to do is: for (k, v) in m.items(): if f(k): # do some processing of v and save result elsewhere del m[k] But this gives (as should be expected

Proper deletion of selected items during map iteration in for loop

2014-04-25 Thread Charles Hixson
during iteration In the past I've accumulated the keys to be deleted in a separate list, but this time there are likely to be a large number of them, so is there some better way? -- Charles Hixson -- https://mail.python.org/mailman/listinfo/python-list

http://bugs.python.org/user?@template=rego_progress broken?

2014-01-21 Thread Charles Hixson
isn't too important, as I was just going to request a documentation change, but it happening may be more important than what I would have entered. -- Charles Hixson -- https://mail.python.org/mailman/listinfo/python-list

Re: 1st Sketch at at ReadOnly dict

2014-01-20 Thread Charles Hixson
On 01/20/2014 08:14 PM, Dan Stromberg wrote: On Mon, Jan 20, 2014 at 12:09 PM, Charles Hixson wrote: class RODict: #Instance Variable Doc ##@var_ddict #This variable holds the reference to the dict. ##Class initializer. #@paramddictThe

Re: 1st Sketch at at ReadOnly dict

2014-01-20 Thread Charles Hixson
On 01/20/2014 04:08 PM, Chris Angelico wrote: On Tue, Jan 21, 2014 at 7:09 AM, Charles Hixson wrote: #@note Instances can be created only from existing dicts. ##Class initializer. #@paramddictThe data dictionary to which this is a read only

Re: 1st Sketch at at ReadOnly dict

2014-01-20 Thread Charles Hixson
On 01/20/2014 12:52 PM, Peter Otten wrote: Charles Hixson wrote: This is just a first sketch, and I haven't yet attempted to test it, so what I'm hoping for is criticisms on the general approach. class RODict: def __init__ (self, ddict = {}): Default values are evaluted just

1st Sketch at at ReadOnly dict

2014-01-20 Thread Charles Hixson
nlen(self._ddict) -- Charles Hixson -- https://mail.python.org/mailman/listinfo/python-list

Documentation of dict views change request

2014-01-19 Thread Charles Hixson
talking about changing their value through other means of access rather than directly through the returned values.) P.S.: Is it reasonable to return the items() of a dict in order to pass a read only copy of the values? -- Charles Hixson -- https://mail.python.org/mailman/listinfo/python-list

Re: converting letters to numbers

2013-10-16 Thread Charles Hixson
tion, but Scheme could be considered a part of the Lisp clade. -- Charles Hixson -- https://mail.python.org/mailman/listinfo/python-list

Re: Tail recursion to while iteration in 2 easy steps

2013-10-09 Thread Charles Hixson
machine, implemented by an underneath microcode layer.) You can reasonably say that an implementation of Python is done in terms of a virtual machine. (Usually I don't bother about this kind of nit-pick, but in this discussion it seems apropos.) -- Charles Hixson -- https://mail.python.org/mailman/listinfo/python-list

Re: class-private names and the Zen of Python

2013-10-09 Thread Charles Hixson
ally show up, as changes that they would catch happen quite rarely, but...) OTOH, neither one really fits in as, say, an included module...they're more like idle, which now that I look does have a "check module" run option. Perhaps that invokes one of them. I note that Idle

Re: Threadpool item mailboxes design problem

2013-04-15 Thread Charles Hixson
On 04/15/2013 10:14 AM, Charles Hixson wrote: On 04/14/2013 07:32 PM, Chris Rebert wrote: On Apr 14, 2013 4:27 PM, "Charles Hixson" <mailto:charleshi...@earthlink.net>> wrote: > > What is the best approach to implementing actors that accept and post messages (a

Re: Threadpool item mailboxes design problem

2013-04-15 Thread Charles Hixson
On 04/14/2013 07:32 PM, Chris Rebert wrote: On Apr 14, 2013 4:27 PM, "Charles Hixson" <mailto:charleshi...@earthlink.net>> wrote: > > What is the best approach to implementing actors that accept and post messages (and have no other external contacts). You migh

Threadpool item mailboxes design problem

2013-04-14 Thread Charles Hixson
space would be wasted. Or if the queues could dynamically resize. Or if there was a threadsafe dict. Or... But I don't know that any of these are feasible. (I mean, yes, I could write all the mail to a database, but is that a better answer, or even a good one?) -- Charles Hixson

Sphinx highlighting

2013-03-13 Thread Charles Hixson
, but I can't stand having it appear for some of my functions, and not for others, and I haven't been able to figure out what turns it on or off. -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

Re: bit count or bit set && Python3

2012-10-26 Thread Charles Hixson
cas...@gmail.com wrote: On Thursday, October 25, 2012 7:56:25 AM UTC-7, Charles Hixson wrote: In Python3 is there any good way to count the number of on bits in an integer (after an& operation)? You may want to look at gmpy2[1] and the popcount() function. Alternatively, is there any

bit count or bit set && Python3

2012-10-25 Thread Charles Hixson
s, or their equivalents in terms of union and intersection.) Or do I need to drop into C for this? -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

Re: bit count or bit set && Python3

2012-10-25 Thread Charles Hixson
ion significantly. Really nice and good to know. I had guessed the other way. (As you point out this is compiler dependent, and I'll be using Python3, but...conversion from an int to a bit string must be a *lot* faster than I had thought.) -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

bit count or bit set && Python3

2012-10-25 Thread Charles Hixson
s, or their equivalents in terms of union and intersection.) Or do I need to drop into C for this? -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

bit count or bit set && Python3

2012-10-25 Thread Charles Hixson
s, or their equivalents in terms of union and intersection.) Or do I need to drop into C for this? -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

Re: 'generator ignored GeneratorExit''

2012-10-20 Thread Charles Hixson
On 10/20/2012 04:28 PM, Ian Kelly wrote: On Sat, Oct 20, 2012 at 2:03 PM, Charles Hixson wrote: If I run the following code in the same module, it works correctly, but if I import it I get the message: Exception RuntimeError: 'generator ignored GeneratorExit' in ignored def

'generator ignored GeneratorExit''

2012-10-20 Thread Charles Hixson
raiseStopIteration The message appears to be purely informational, but I *would* like to fix whatever problem it's reporting, and none of the changes that I've tried have worked. What *should* I be doing? -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

Re: exception problem

2012-06-27 Thread Charles Hixson
On 06/25/2012 12:48 AM, Steven D'Aprano wrote: On Sun, 24 Jun 2012 16:16:25 -0700, Charles Hixson wrote: But what I wanted was to catch any exception. Be careful of what you ask for, since you might get it. "Catch any exception" is almost certainly the wrong thin

Re: exception problem

2012-06-25 Thread Charles Hixson
On 06/24/2012 11:23 PM, Andrew Berg wrote: On 6/25/2012 12:27 AM, Charles Hixson wrote: The documentation section covering the except statement could stand to be a *LOT* clearer. I read the sections on the except statement and exception handlers several times and couldn't figure ou

Re: exception problem

2012-06-24 Thread Charles Hixson
On 06/24/2012 03:43 PM, Charles Hixson wrote: On 06/24/2012 03:36 PM, Chris Angelico wrote: On Mon, Jun 25, 2012 at 8:26 AM, Charles Hixson wrote: The code: finally: print ("at finally") print ("chunks =") produces

Re: exception problem

2012-06-24 Thread Charles Hixson
On 06/24/2012 03:43 PM, MRAB wrote: On 24/06/2012 23:26, Charles Hixson wrote: The code: print("pre-chunkLine") chunks=[] try: chunks=self.chunkLine (l)

Re: exception problem

2012-06-24 Thread Charles Hixson
Sorry, I left out: er$ python3 --version Python 3.2.3rc1 On 06/24/2012 03:26 PM, Charles Hixson wrote: The code: print("pre-chunkLine") chunks=[] try: chunks=self.chunkLine (l)

exception problem

2012-06-24 Thread Charles Hixson
ons as to what's wrong with the code? FWIW, chunkLine begins: def chunkLine (self, line): print("chunkLine: ") print ("line = ", line) ifline == None: return[] assert(isinstance (line, str) ) -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

Re: Unexpected exception thrown in __del__

2012-05-21 Thread Charles Hixson
On 05/21/2012 08:29 AM, Charles Hixson wrote: message excerpt: flush: sql = insert or replace into persists (id, name, data, rdCnt, rdTim, wrCnt, wrTim, deprecation) values (?, ?, ?, ?, ?, ?, ?, ?) Exception TypeError: "'NoneType' object is not callable" in method Shelve2.

Unexpected exception thrown in __del__

2012-05-21 Thread Charles Hixson
re the class, thus: defnowI(): t=int (time() * 100) returnt All I can guess is that there's some reason that an external to the class function shouldn't be called during a __del__. Is this correct? -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

Re: Questions on __slots__

2012-05-19 Thread Charles Hixson
On 05/19/2012 06:39 AM, Adam Tauno Williams wrote: On Fri, 2012-05-18 at 09:53 -0700, Charles Hixson wrote: Does __slots__ make access to variables more efficient? Absolutely, yes. If one uses property() to create a few read-only pseudo-variables, does that negate the

Questions on __slots__

2012-05-18 Thread Charles Hixson
Does __slots__ make access to variables more efficient? If one uses property() to create a few read-only pseudo-variables, does that negate the efficiency advantages of using __slots__? (Somehow I feel the documentation needs a bit of improvement.) -- Charles Hixson -- http://mail.python.org

Re: non-pickle persistance for dicts?

2012-05-16 Thread Charles Hixson
On 05/16/2012 03:11 PM, Ian Kelly wrote: On Wed, May 16, 2012 at 3:52 PM, Charles Hixson wrote: I want to persist simple dicts, but due to the security problems with (un)pickle, I'd prefer to not use shelve, and the only way I could see to persist them onto sqlite also invoked pickle

non-pickle persistance for dicts?

2012-05-16 Thread Charles Hixson
e a simple convert to and from either bytes or strings. repr works well for the conversion into string (I said they were simple), but I'd really rather be able to turn "{'a': 'A', 1: 23, 2: ['b', 2]}" back into a dict without allowing the execution of arb

Re: indexed property? Can it be done?

2012-05-08 Thread Charles Hixson
On 05/08/2012 01:19 PM, Adam Tauno Williams wrote: On Mon, 2012-05-07 at 20:15 -0700, Charles Hixson wrote: class Node: def__init__(self, nodeId, key, value, downRight, downLeft, parent): dirty=True dlu=utcnow() self.node

Re: indexed property? Can it be done?

2012-05-08 Thread Charles Hixson
On 05/08/2012 12:50 AM, Peter Otten wrote: Charles Hixson wrote: class Node: def__init__(self, nodeId, key, value, downRight, downLeft, parent): dirty=True dlu=utcnow() self.node=[nodeId, downLeft, [key], [value

Re: indexed property? Can it be done?

2012-05-07 Thread Charles Hixson
On 05/07/2012 08:44 PM, Dan Sommers wrote: On Mon, 07 May 2012 20:15:36 -0700 Charles Hixson wrote: class Node: def__init__(self, nodeId, key, value, downRight, downLeft, parent): dirty=True dlu=utcnow() self.node=[nodeId, downLeft

Re: indexed property? Can it be done?

2012-05-07 Thread Charles Hixson
On 05/07/2012 08:33 PM, Chris Rebert wrote: On Mon, May 7, 2012 at 8:15 PM, Charles Hixson wrote: class Node: def__init__(self, nodeId, key, value, downRight, downLeft, parent): dirty=True dlu=utcnow() self.node=[nodeId, downLeft

indexed property? Can it be done?

2012-05-07 Thread Charles Hixson
node[3] is a list of values, etc. What I'd like to do is to be able to address them thusly: k = node.key[2] v = node.value[2] but if there's a way to do this, I haven't been able to figure it out. Any suggestions? -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

Re: Possible bug in string handling (with kludgy work-around)

2011-12-27 Thread Charles Hixson
That was it! Thanks. On 12/26/2011 02:44 PM, Chris Angelico wrote: On Tue, Dec 27, 2011 at 9:23 AM, Charles Hixson wrote: This doesn't cause a crash, but rather incorrect results. You may need to be a bit clearer. What line of code (or what expression)? What did you expect t

Possible bug in string handling (with kludgy work-around)

2011-12-26 Thread Charles Hixson
quot;\"", sep = "") tmp=self.wordList[i][1] ## !! Kludge -- remove tmp to see the error self.wordList[i]=tmp + self.wordList[i][1:-1] ## !! Kludge -- remove tmp + to see the error print ("1: wordList[", i, "] = \"", self.wordList[i], "\"", sep = "") print("len(wordList[", i, "]) = ", len(self.wordList[i]) ) -- Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list

Re: Python and Flaming Thunder

2008-05-22 Thread Charles Hixson
On Thursday 22 May 2008 13:30:07 Nick Craig-Wood wrote: > ... > >From Armstrong's book: The expression Pattern = Expression causes > > Expression to be evaluated and the result matched against Pattern. The > match either succeeds or fails. If the match succeeds any variables > occurring in Pattern

comparison puzzle? bug?

2005-03-22 Thread Charles Hixson
I hesitate to call this a bug, as at my level of expertise that seems ... unlikely. But I can't think of any other explanation: This is an extract from some longer code: print"item = ", item print"item[0] < lvl = %d < %d = " %(item[0], lvl), bool(item[0] < lvl) print"item[0] == lv

Re: Boo who? (was Re: newbie question)

2005-03-15 Thread Charles Hixson
Grant Edwards wrote: That seems to imply that you think market sucess == technical merits. Unless you mean that Prothon was a technical failure rather than a market-share failure... As Prothon never got as far as an alpha stage product, I don't think you could call it a technical success. It

Re: Boo who? (was Re: newbie question)

2005-03-15 Thread Charles Hixson
Terry Reedy wrote: "Luis M. Gonzalez" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] ... It is as important and "python related" as other projects such as PyPy, Stackless, but I think this is silly. PyPy is an alternate implementation of Python, not a different language.