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How can I check if my python object is a number? [duplicate]
In Java the numeric types all descend from Number so I would use
5 Answers
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UITableViewCell subview disappears when cell is selected
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UITableViewCell changes the background color of all sub views when cell is selected or highlighted ,You can Solve this problem by overriding Tableview cell's setSelected:animated and setHighlighted:animated and resetting view background color.
In Objective C :
- (void)se...
Anatomy of a “Memory Leak”
... seen is in Chapter 7 of the free Foundations of Programming e-book.
Basically, in .NET a memory leak occurs when referenced objects are rooted and thus cannot be garbage collected. This occurs accidentally when you hold on to references beyond the intended scope.
You'll know that you have leaks w...
Best practices: throwing exceptions from properties
...roperties at http://msdn.microsoft.com/en-us/library/ms229006.aspx
Essentially, they recommend that property getters be lightweight accessors that are always safe to call. They recommend redesigning getters to be methods if exceptions are something you need to throw. For setters they indicate that ...
How to enumerate an object's properties in Python?
...oes not return dynamic members (i.e., object attributes and methods dynamically defined by that object's __getattr__() method or similar magic). In all likelihood, your desired file.ImplementationName property is defined dynamically and hence not available to vars() or dir().
–...
How to clone ArrayList and also clone its contents?
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You can't do it generically, though. clone() is not part of the Cloneable interface.
– Michael Myers♦
Apr 3 '09 at 20:47
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How to skip over an element in .map()?
...nce it has some cost, you can use the more general .reduce(). You can generally express .map() in terms of .reduce:
someArray.map(function(element) {
return transform(element);
});
can be written as
someArray.reduce(function(result, element) {
result.push(transform(element));
return result;
}...
Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_
...AMD documents it and compilers don't expose it.)
(Yes, these instructions all run on the same execution unit).
This dependency doesn't just hold up the 4 popcnts from a single loop iteration. It can carry across loop iterations making it impossible for the processor to parallelize different loop...
Vim: insert the same characters across multiple lines
...e the screen in the first line - until Esc is pressed (6.), at which point all lines will be updated.
Press Esc.
An uppercase I must be used rather than a lowercase i, because the lowercase i is interpreted as the start of a text object, which is rather useful on its own, e.g. for selecting insi...
What is the real overhead of try/catch in C#?
... to make here:
Firstly, there is little or NO performance penalty in actually having try-catch blocks in your code. This should not be a consideration when trying to avoid having them in your application. The performance hit only comes into play when an exception is thrown.
When an exception is th...