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MongoDB/Mongoose querying at a specific date?
...onents. To query those times you need to create a date range that includes all moments in a day.
db.posts.find( //query today up to tonight
{"created_on": {"$gte": new Date(2012, 7, 14), "$lt": new Date(2012, 7, 15)}})
s...
Why isn't sizeof for a struct equal to the sum of sizeof of each member?
... errors.
Here's an example using typical settings for an x86 processor (all used 32 and 64 bit modes):
struct X
{
short s; /* 2 bytes */
/* 2 padding bytes */
int i; /* 4 bytes */
char c; /* 1 byte */
/* 3 padding bytes */
};
struct Y
{
int i; /* 4...
Does use of final keyword in Java improve the performance?
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Usually not. For virtual methods, HotSpot keeps track of whether the method has actually been overridden, and is able to perform optimizations such as inlining on the assumption that a method hasn't been overridden - until it lo...
How to Apply Gradient to background view of iOS Swift App
...ems you may face with this is that when you add a sublayer it may sit over all your other items, labels, image, etc. To overcome this create another view that sits below everything and set its constraints to that of the container you want the gradient in. Then set the gradient to be applied to this ...
What are C++ functors and their uses?
...42); // create an instance of the functor class
int i = add42(8); // and "call" it
assert(i == 50); // and it added 42 to its argument
std::vector<int> in; // assume this contains a bunch of values)
std::vector<int> out(in.size());
// Pass a functor to std::transform, which calls the fu...
What does the caret operator (^) in Python do?
...his way:
1000 # 8 (binary)
0011 # 3 (binary)
---- # APPLY XOR ('vertically')
1011 # result = 11 (binary)
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Alternatives to gprof [closed]
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Valgrind has an instruction-count profiler with a very nice visualizer called KCacheGrind. As Mike Dunlavey recommends, Valgrind counts the fraction of instructions for which a procedure is live on the stack, although I'm sorry to say it appears to become confused in the presence of mutual recur...
Concatenate two slices in Go
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Is this at all performant when the slices are quite big? Or does the compiler not really pass all the elements as parameters?
– Toad
Sep 24 '14 at 8:57
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How to make a python, command-line program autocomplete arbitrary things NOT interpreter
...ts, i.e. --help, --verbose and --version. For your purposes, you'll essentially want to customise the values that are put into opts.
Do have a look at the example on the linked page, it's all pretty straightforward.
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What are the differences between .so and .dylib on osx?
...xecutables and libraries distinguishes between shared libraries and dynamically loaded modules. Use otool -hv some_file to see the filetype of some_file.
Mach-O shared libraries have the file type MH_DYLIB and carry the extension .dylib. They can be linked against with the usual static linker flags...