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List of lists changes reflected across sublists unexpectedly
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When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references to the same x. When you then modify this single x it is visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 1405608979...
jQuery get value of selected radio button
...use you when you're used to seeing "" as the default value via the .val() call.
– xji
Jan 8 '18 at 22:30
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show 1 more comment
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How do I add custom field to Python log format string?
...LoggerAdapter so you don't have to pass the extra info with every logging call:
import logging
extra = {'app_name':'Super App'}
logger = logging.getLogger(__name__)
syslog = logging.StreamHandler()
formatter = logging.Formatter('%(asctime)s %(app_name)s : %(message)s')
syslog.setFormatter(formatte...
Formatting code snippets for blogging on Blogger [closed]
... I spent a couple hours on it and I can't get this to work at all.
– thepaulpage
Mar 21 '13 at 15:43
2
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How do I dump an object's fields to the console?
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Adding an inspect method to your class allows you to define how the class' attributes are displayed, rather than rely on default output. A lot of classes don't implement it well, but it can be really useful when debugging. Ruby will fall back to to_s if it can't f...
Exit codes in Python
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What you're looking for in the script is calls to sys.exit(). The argument to that method is returned to the environment as the exit code.
It's fairly likely that the script is never calling the exit method, and that 0 is the default exit code.
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How do I create delegates in Objective-C?
...ign it as the web view's delegate:
MyClass *instanceOfMyClass = [[MyClass alloc] init];
myWebView.delegate = instanceOfMyClass;
On the UIWebView side, it probably has code similar to this to see if the delegate responds to the webViewDidStartLoad: message using respondsToSelector: and send it if ...
Reintegrate can only be used if revisions X through Y were previously merged from to reintegra
Been using SVN branches with Tortoise 1.6. I've been periodically merging the trunk into the branch to keep it up to date.
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What is meant by Resource Acquisition is Initialization (RAII)?
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It's a really terrible name for an incredibly powerful concept, and perhaps one of the number 1 things that C++ developers miss when they switch to other languages. There has been a bit of a movement to try to rename this concept as ...
CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清泛网移动版 - 专注IT技能提升
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...