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LINQ Select Distinct with Anonymous Types
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Have a read through K. Scott Allen's excellent post here:
And Equality for All ... Anonymous Types
The short answer (and I quote):
Turns out the C# compiler overrides
Equals and GetHashCode for anonymous
types. The impleme...
When should you use 'friend' in C++?
I have been reading through the C++ FAQ and was curious about the friend declaration. I personally have never used it, however I am interested in exploring the language.
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String vs. StringBuilder
... clarity before performance. As developers, we spend as much or more time reading code as we do writing it.
– Scott Lawrence
Sep 16 '08 at 18:18
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Compelling examples of custom C++ allocators?
...l TBB's custom STL allocator significantly improve performance of a multithreaded app simply by changing a single
std::vector<T>
to
std::vector<T,tbb::scalable_allocator<T> >
(this is a quick and convenient way of switching the allocator to use TBB's nifty thread-private he...
Should I instantiate instance variables on declaration or in the constructor?
...ually put in the constructor(s) by the compiler.
The first variant is more readable.
You can't have exception handling with the first variant.
There is additionally the initialization block, which is as well put in the constructor(s) by the compiler:
{
a = new A();
}
Check Sun's explanation ...
How to pass an array into jQuery .data() attribute
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@Alnitak Then I'm high, because I read pretty much the entire data section and many of the comments before posting. I just looked again even.
– John Green
May 20 '11 at 12:55
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setNeedsLayout vs. setNeedsUpdateConstraints and layoutIfNeeded vs updateConstraintsIfNeeded
...aints using setNeedsUpdateConstraints is pretty rare too, objc.io–a must read about autolayouts–says:
If something changes later on that invalidates one of your constraints, you should remove the constraint immediately and call setNeedsUpdateConstraints. In fact, that’s the only case where...
java.lang.IllegalStateException: Cannot (forward | sendRedirect | create session) after response has
...w to use Servlets the right way.
See also:
What exactly does "Response already committed" mean? How to handle exceptions then?
Unrelated to your concrete problem, your JDBC code is leaking resources. Fix that as well. For hints, see also How often should Connection, Statement and ResultSet be cl...
How do I prevent 'git diff' from using a pager?
...e text to the left to see what was cut off.
Those modifications were already visible in git 1.8.x, as illustrated in "Always use the pager for git diff" (see the comments).
But the documentation just got reworded (for git 1.8.5 or 1.9, Q4 2013).
Text viewer for use by Git commands (e.g., ...
How many database indexes is too many?
...ntenance whenever data is added to the table. On tables that are primarily read only, lots of indexes are a good thing. On tables that are highly dynamic, fewer is better.
My advice is to cover the common and obvious cases and then, as you encounter issues where you need more speed in getting data ...