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Why is it faster to check if dictionary contains the key, rather than catch the exception in case it
...onary by its key is cheap, because it's a fast, O(1) operation.
BTW: The correct way to do this is to use TryGetValue
obj item;
if(!dict.TryGetValue(name, out item))
return null;
return item;
This accesses the dictionary only once instead of twice.
If you really want to just return null if t...
Working with huge files in VIM
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I had a 12GB file to edit today. The vim LargeFile plugin did not work for me. It still used up all my memory and then printed an error message :-(. I could not use hexedit for either, as it cannot insert anything, just overwrite. Here is an alternative approach:
You split the file, edit th...
What is the difference between & and && in Java?
I always thought that && operator in Java is used for verifying whether both its boolean operands are true , and the & operator is used to do Bit-wise operations on two integer types.
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How to pass a variable from Activity to Fragment, and pass it back?
...create it, and you can retrieve this argument later on the method onCreate or onCreateView of your fragment.
On the newInstance function of your fragment you add the arguments you wanna send to it:
/**
* Create a new instance of DetailsFragment, initialized to
* show the text at 'index'.
*/
pu...
When should you use constexpr capability in C++11?
It seems to me that having a "function that always returns 5" is breaking or diluting the meaning of "calling a function". There must be a reason, or a need for this capability or it wouldn't be in C++11. Why is it there?
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Detect if called through require or directly by command line
...n I detect whether my Node.JS file was called using SH: node path-to-file or JS: require('path-to-file') ?
5 Answers
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How to retrieve all keys (or values) from a std::map and put them into a vector?
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While your solution should work, it can be difficult to read depending on the skill level of your fellow programmers. Additionally, it moves functionality away from the call site. Which can make maintenance a little more difficult.
I'm not sure if you...
What is difference between instantiating an object using new vs. without
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By contrast:
Time* t = new Time(12, 0, 0);
... allocates a block of memory by calling either ::operator new() or Time::operator new(), and subsequently calls Time::Time() with this set to an address within that memory block (and also returned as the result of new), which is then stored in t. As ...
Android Endless List
...list where when you reach the end of the list I am notified so I can load more items?
10 Answers
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Determine function name from within that function (without using traceback)
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Python doesn't have a feature to access the function or its name within the function itself. It has been proposed but rejected. If you don't want to play with the stack yourself, you should either use "bar" or bar.__name__ depending on context.
The given rejection notice is:
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