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Why does += behave unexpectedly on lists?
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The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...
Get all related Django model objects
How can I get a list of all the model objects that have a ForeignKey pointing to an object? (Something like the delete confirmation page in the Django admin before DELETE CASCADE).
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Is there any way to put malicious code into a regular expression?
... spent begging the operating system for more space, and the attendant page-table set-up costs, can sometimes nudge the balancing scale further the other way and make the conversion from time to space less attractive than it would be.
– tchrist
Jan 19 '11 at 18:...
Is there a way that I can check if a data attribute exists?
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if ($("#dataTable").data('timer')) {
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}
NOTE this only returns true if the data attribute is not empty string or a "falsey" value e.g. 0 or false.
If you want to check for the existence of the data attribute, even if empty, do th...
How do you round a floating point number in Perl?
.... For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3.142
The POSIX module (part of the standard Perl distribution) implements
ceil(), floor(), and a number of other mathematical and trigonometric
func...
Cleanest way to get last item from Python iterator
...specific default value could even be correct? If the iterator doesn't actually iterate, then an out-of-band value is more meaningful than some misleading function-specific default.
– S.Lott
Jan 26 '10 at 11:44
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C#: Assign same value to multiple variables in single statement
...nteresting to know that the get accessor of the intermediate value is not called. Only the set accessor is invoked for all property accessed in the assignation sequence.
Take for example a class that write to the console everytime the get and set accessor are invoked.
static void Main(string[] arg...
JPA and Hibernate - Criteria vs. JPQL or HQL
...ytime you fire a query using criteriaQuery, it creates a new alias for the table name which does not reflect in the last queried cache for any DB. This leads to an overhead of compiling the generated SQL, taking more time to execute.
Regarding fetching strategies [http://www.hibernate.org/315.html]...
Multiple inheritance/prototypes in JavaScript
...second, and so on. Once a property has been iterated, I store it in a hash table to avoid iterating it again.
Warning: This trap has been removed in ES7 draft and is deprecated in browsers.
The ownKeys trap is a trap for Object.getOwnPropertyNames(). Since ES7, for...in loops keep calling [[GetProto...
How does JavaScript .prototype work?
...ing languages but I've written my fair share of JavaScript code. I never really got my head around this prototype-based programming, does any one know how this works?
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