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What is Lazy Loading?
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It's called lazy loading because, like a lazy person, you are putting off doing something you don't want to. The opposite is Eager Loading, where you load something right away, long before you need it.
If you are curious why peop...
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...
C++ display stack trace on exception
...re details.
On MSVC then you can use the StackWalker library that handles all of the underlying API calls needed for Windows.
You'll have to figure out the best way to integrate this functionality into your app, but the amount of code you need to write should be minimal.
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How to send an email from JavaScript
...ject=subject&body=body');
Another solution would be to do an ajax call to your server, so that the server sends the email. Be careful not to allow anyone to send any email through your server.
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What is the pythonic way to avoid default parameters that are empty lists?
...he preferred way in this example is to say: if working_list is None . The caller might have used an empty list-like object with a custom append.
– tzot
Dec 14 '08 at 12:45
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What’s the best way to check if a file exists in C++? (cross platform)
...his using standard c++ libs? Preferably without trying to open the file at all.
10 Answers
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How to prevent IFRAME from redirecting top-level window
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iFrames do allow cross-domain communication, though, using postMessage. This isn't a security risk, but someone might care to know that this capability exists when they see your comment. :)
– coreyward
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Why rename synthesized properties in iOS with leading underscores? [duplicate]
...s is an artifact of a previous version of the Objective-C runtime.
Originally, @synthesize was used to create accessors methods, but the runtime still required that instance variables had to be instantiated explicitly:
@interface Foo : Bar {
Baz *_qux;
}
@property (retain) Baz *qux;
@end
@imp...
The relationship could not be changed because one or more of the foreign-key properties is non-nulla
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You should delete old child items thisParent.ChildItems one by one manually. Entity Framework doesn't do that for you. It finally cannot decide what you want to do with the old child items - if you want to throw them away or if you want to keep and assign them to other parent entities. You must ...
Format floats with standard json module
...loat class in Tom Wuttke's answer works, but only if %g encoding works globally for your application. The %.15g is a bit magic, it works because float precision is 17 significant digits and %g does not print trailing zeroes.
I spent some time trying to make a PrettyFloat that allowed customization ...