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Best way to test for a variable's existence in PHP; isset() is clearly broken
...l scope variables as well, on can do a $defined_vars = get_defined_vars(); and then test via array_key_exists('v', $defined_vars);.
– Henrik Opel
Sep 27 '10 at 16:01
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Which encoding opens CSV files correctly with Excel on both Mac and Windows?
...s CSV files containing foreign characters with UTF-8, no BOM. Both Windows and Mac users get garbage characters in Excel. I tried converting to UTF-8 with BOM; Excel/Win is fine with it, Excel/Mac shows gibberish. I'm using Excel 2003/Win, Excel 2011/Mac.
Here's all the encodings I tried:
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Array.Copy vs Buffer.BlockCopy
Array.Copy and Buffer.BlockCopy both do the same thing, but BlockCopy is aimed at fast byte-level primitive array copying, whereas Copy is the general-purpose implementation. My question is - under what circumstances should you use BlockCopy ? Should you use it at any time when you are copyi...
Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
I've been profiling some of our core math on an Intel Core Duo, and while looking at various approaches to square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!...
When should we use intern method of String on String literals
...in String pool, otherwise a new string object will be added in String pool and the reference of this String is returned.
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When to use references vs. pointers
I understand the syntax and general semantics of pointers versus references, but how should I decide when it is more-or-less appropriate to use references or pointers in an API?
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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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NHibernate vs LINQ to SQL
...orld projects I wonder if anyone knows how these two complement each other and how much their functionalities overlap?
9 An...
Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference
...nicity.
Forewords
This topic has been iterated at least a couple of thousands of times, here, in Stack Overflow. Hence, first off I'd like to point out some extremely useful resources:
@Felix Kling's answer to "How do I return the response from an asynchronous call?". See his excellent answer ex...
When should I use C++14 automatic return type deduction?
...11 raises similar questions: when to use return type deduction in lambdas, and when to use auto variables.
The traditional answer to the question in C and C++03 has been "across statement boundaries we make types explicit, within expressions they are usually implicit but we can make them explicit w...