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What's the best way of scraping data from a website? [closed]
I need to extract contents from a website, but the application doesn’t provide any application programming interface or another mechanism to access that data programmatically.
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Why is i++ not atomic?
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i++ is probably not atomic in Java because atomicity is a special requirement which is not present in the majority of the uses of i++. That requirement has a significant overhead: there is a large cost in making an increment operation atomic; it involves synchronization at ...
What is a void pointer in C++? [duplicate]
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A void* does not mean anything. It is a pointer, but the type that it points to is not known.
It's not that it can return "anything". A function that returns a void* generally is doing one of the following:
It is dealing in unformatted memory. This is wh...
Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable
...mory. Than Garbage Collector has to take care of them. If you are dealing with high throughput application, it could be noticeable impact.
Enumerable.Empty does not create an object per call thus putting less load on GC.
If the code is in low-throughput location, then it boils down to aesthetic co...
Xcode 4 - slow performance
I have an issue with Xcode 4 really responding very slowly to user interactions, e.g. editing code, scrolling areas etc. This particularly happens with larger scale projects with many controllers/view files etc.
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A clean, lightweight alternative to Python's twisted? [closed]
A (long) while ago I wrote a web-spider that I multithreaded to enable concurrent requests to occur at the same time. That was in my Python youth, in the days before I knew about the GIL and the associated woes it creates for multithreaded code (IE, most of the time stuff just ends up serialized!...
What are the barriers to understanding pointers and what can be done to overcome them? [closed]
...s is a concept that for many can be confusing at first, in particular when it comes to copying pointer values around and still referencing the same memory block.
I've found that the best analogy is to consider the pointer as a piece of paper with a house address on it, and the memory block it refer...
JavaScript checking for null vs. undefined and difference between == and ===
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How do I check a variable if it's null or undefined...
Is the variable null:
if (a === null)
// or
if (a == null) // but see note below
...but note the latter will also be true if a is undefined.
Is it undefined:
if (typeof a === "undefined")
// o...
Programming with white text on black background?
Does anyone program with white text against black background? I have heard some rumors that it is better for your eyes. What's the case? Is it any better than the traditional black on white? What are the pros and cons?
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Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
...ions,the C# compiler treats a null string the same as an empty string, but it does not convert the value of the original null string.
More information on the + binary operator:
The binary + operator performs string concatenation when one or both operands are of type string.
If an operand of string...