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Why are local variables not initialized in Java?
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Local variables are declared mostly to do some calculation. So its the programmer's decision to set the value of the variable and it should not take a default value. If the programmer, by mistake, did not initialize a local variable and it take default value, then the output could be som...
Blocks and yields in Ruby
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Yes, it is a bit puzzling at first.
In Ruby, methods may receive a code block in order to perform arbitrary segments of code.
When a method expects a block, it invokes it by calling the yield function.
This is very handy, fo...
Error when testing on iOS simulator: Couldn't register with the bootstrap server
I was testing my app on the simulator when it crashed on clicking a button of a UIAlertView. I stopped debugging there, made some changes to the code and built the app again. Now when I run the application, I get this error in the console
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opengl: glFlush() vs. glFinish()
... OpenGL. glFlush ensures that previous OpenGL commands must complete in finite time (OpenGL 2.1 specs, page 245). If you draw directly to the front buffer, this shall ensure that the OpenGL drivers starts drawing without too much delay. You could think of a complex scene that appears object after ob...
throwing exceptions out of a destructor
...ed behavior. Stroustrup makes the point that "the vector destructor explicitly invokes the destructor for every element. This implies that if an element destructor throws, the vector destruction fails... There is really no good way to protect against exceptions thrown from destructors, so the libra...
How to recover stashed uncommitted changes
I had some uncommitted changes in my development branch and I stashed them using git stash , but there were some changes which were very important among those stashed ones. Is there any way to get back those changes?
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Is JavaScript a pass-by-reference or pass-by-value language?
The primitive types (number, string, etc.) are passed by value, but objects are unknown, because they can be both passed-by-value (in case we consider that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object hol...
How do I install from a local cache with pip?
...pdated Answer 19-Nov-15
According to the Pip documentation:
Starting with v6.0, pip provides an on by default cache which functions similarly to that of a web browser. While the cache is on by default and is designed do the right thing by default you can disable the cache and always access PyPI...
Using async/await for multiple tasks
...g an API client that is completely asynchrounous, that is, each operation either returns Task or Task<T> , e.g:
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Setting an object to null vs Dispose()
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It's important to separate disposal from garbage collection. They are completely separate things, with one point in common which I'll come to in a minute.
Dispose, garbage collection and finalization
When you write a using ...