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by: Rami A. Kishek |
last post by:
Hi - this mysterious behavior with shelve is just about to kill me. I
hope someone here can shed some light. First of all, I have this piece
of code which uses shelve to save instances of some class I define. It
works perfectly on an old machine (PII-400) running Python 2.2.1 under
RedHat Linux 8.0. When I try to run it under Python for windows ME on a
P-4 1.4 GHz, however, it keeps crashing on reading from the shelved file
the second...
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by: Kris Caselden |
last post by:
Python's docs say that Shelve uses Pickle to serialize its data.
However, I've noticed that Pickle can maintain internal links, while
Shelve cannot. For instance:
>>> d = shelve.open('shelvedata.txt',writeback=True)
>>> d=
>>> d=d
>>> print d {'a': , 'b': }
>>> d=2
>>> print d {'a': , 'b': }
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by: seth |
last post by:
Last week I encountered an AttributeError in my unit tests that I
wasn'table to catch with an "except AttributeError" statement.
The problem stemmed from a class that raised an error inside
__init__and defined a __del__ method to clean up resources. I then
discovered asimilar problem in the shelve module. This led me to two
importantdiscoveries:
1. Attributes defined in __init__ after an error is raised will not be
apart of the...
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by: Paul Rubin |
last post by:
Shelve uses dbm and pickle to make a persistent object store. The
"db" in "dbm" stands for "database" and while I didn't expect full
ACID capability, I'd have thought there'd be at least some minimum
gesture towards durability of updates. But say that s is a shelve
object. If I say
s = value
there is no way apparent from the shelve docs to get the update
flushed out to the disk file until the shelve is actually closed. If
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by: josegomez |
last post by:
Hi!
I want to use shelve to store lists which are indexed by an integer
key. The keys are not concurrent or anything, they are just defined as
integer values. However, shelve complains that I cannot have integer
keys. Here's the error:
>>> d
Traceback (most recent call last):
File "<input>", line 1, in ?
File "E:\Python23\lib\shelve.py", line 118, in __getitem__
f = StringIO(self.dict)
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by: Michele Petrazzo |
last post by:
Hi,
I'm trying a script on a debian 3.1 that has problems on shelve library.
The same script work well on a fedora 2 and I don't know why it create
this problem on debian:
#extract from my code
import shelve
class XX:
def __init__(self):
self._data = shelve.open("/tmp/myfile")
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by: aomighty |
last post by:
I wanted to write the following code:
import shelve
try:
db = shelve.open(file, "r")
except SomeError:
print "Oh no, db not found"
Only, I'm not sure what SomeError should be. I tried error,
anydbm.error, shelve.open.anydb.error, etc. but can't find it. Things
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by: 7stud |
last post by:
test1.py:
--------------------
import shelve
s = shelve.open("/Users/me/2testing/dir1/aaa.txt")
s = "red"
s.close()
--------output:------
$ python test1.py
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by: gluckj |
last post by:
Hi,
I'm not a Win ME fan myself (I'm a Mac user), but I'm here in Thailand
developing software for special-needs kids, and the test PC in my home
office is a Win ME machine (sigh). So when I ported my Python program
today to the PC, it quickly crashed. Everything seems to work except
for shelve. Using the latest version of Python (2.5.1), when I do the
following in IDLE on the Win ME machine here's the result:
Python 2.5.1...
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by: marktang |
last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main usage, and What is the difference between ONU and Router. Let’s take a closer look !
Part I. Meaning of...
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by: Hystou |
last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it.
First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
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by: Oralloy |
last post by:
Hello folks,
I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>".
The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed.
This is as boiled down as I can make it.
Here is my compilation command:
g++-12 -std=c++20 -Wnarrowing bit_field.cpp
Here is the code in...
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by: Hystou |
last post by:
Overview:
Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
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by: tracyyun |
last post by:
Dear forum friends,
With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each protocol has its own unique characteristics and advantages, but as a user who is planning to build a smart home system, I am a bit confused by the choice of these technologies. I'm particularly interested in Zigbee because I've heard it does some...
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by: agi2029 |
last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing, and deployment—without human intervention. Imagine an AI that can take a project description, break it down, write the code, debug it, and then launch it, all on its own....
Now, this would greatly impact the work of software developers. The idea...
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by: adsilva |
last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
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by: muto222 |
last post by:
How can i add a mobile payment intergratation into php mysql website.
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by: bsmnconsultancy |
last post by:
In today's digital era, a well-designed website is crucial for businesses looking to succeed. Whether you're a small business owner or a large corporation in Toronto, having a strong online presence can significantly impact your brand's success. BSMN Consultancy, a leader in Website Development in Toronto offers valuable insights into creating effective websites that not only look great but also perform exceptionally well. In this comprehensive...
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