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What is the difference between mutex and critical section?
... between the two of them. On my system for 1,000,000 uncontended acquires and releases, a mutex takes over one second. A critical section takes ~50 ms for 1,000,000 acquires.
Here's the test code, I ran this and got similar results if mutex is first or second, so we aren't seeing any other effect...
Getting a structural type with an anonymous class's methods from a macro
...a macro that defines an anonymous class with some type members or methods, and then creates an instance of that class that's statically typed as a structural type with those methods, etc. This is possible with the macro system in 2.10.0, and the type member part is extremely easy:
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Why is processing a sorted array faster than processing an unsorted array?
...e long distance or radio communication.
You are the operator of a junction and you hear a train coming. You have no idea which way it is supposed to go. You stop the train to ask the driver which direction they want. And then you set the switch appropriately.
Trains are heavy and have a lot of inert...
Optional Parameters in Go?
...optional parameters? Or can I just define two functions with the same name and a different number of arguments?
12 Answers
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Clearing a string buffer/builder after loop
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Ah, I think sb.setLength(0); is cleaner and more efficient than declaring it inside the loop. Your solution goes against the performance benefit of using StringBuffer...
– Jon
Feb 11 '10 at 5:38
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Is there a goto statement in Java?
...were to be added to a later version of Java.
If goto was not on the list, and it gets added to the language later on, existing code that used the word goto as an identifier (variable name, method name, etc...) would break. But because goto is a keyword, such code will not even compile in the presen...
How to get Linux console window width in Python
...mns = os.popen('stty size', 'r').read().split()
uses the 'stty size' command which according to a thread on the python mailing list is reasonably universal on linux. It opens the 'stty size' command as a file, 'reads' from it, and uses a simple string split to separate the coordinates.
Unlike the...
Does PowerShell support constants?
...iable test -option ReadOnly -value 100
The difference between "Constant" and "ReadOnly" is that a read-only variable can be removed (and then re-created) via
Remove-Variable test -Force
whereas a constant variable can't be removed (even with -Force).
See this TechNet article for more details.
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Does delete on a pointer to a subclass call the base class destructor?
...s a heap memory allocation for one of its fields. Class A is instantiated and stored as a pointer field in another class ( class B .
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Equivalent of LIMIT and OFFSET for SQL Server?
In PostgreSQL there is the Limit and Offset keywords which will allow very easy pagination of result sets.
16 Answers
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