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What is the difference between _tmain() and main() in C++?
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_tmain does not exist in C++. main does.
_tmain is a Microsoft extension.
main is, according to the C++ standard, the program's entry point.
It has one of these two signatures:
int main();
int main(int argc, char* argv[]);...
How to use filter, map, and reduce in Python 3
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@Breezer actually i**3 will call i.__pow__(3) and i*i*i i.__mul__(i).__mul__(i) (or something like that). With ints it doesn't matter but with numpy numbers/custom classes it might even produce different results.
– syntonym
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Do try/catch blocks hurt performance when exceptions are not thrown?
...TryCatch() cil managed
{
// Code size 32 (0x20)
.maxstack 8
IL_0000: nop
IL_0001: ldstr "SIN(1) = {0} - No Try/Catch"
IL_0006: ldc.r8 1.
IL_000f: call float64 [mscorlib]System.Math::Sin(float64)
IL_0014: box [mscorlib]System.Double
IL_0019: call ...
What's the difference between :: (double colon) and -> (arrow) in PHP?
...called or a subclass of it.
Example:
class A {
public function func_instance() {
echo "in ", __METHOD__, "\n";
}
public function callDynamic() {
echo "in ", __METHOD__, "\n";
B::dyn();
}
}
class B extends A {
public static $prop_static = 'B::$prop_st...
Is there a range class in C++11 for use with range based for loops?
...C++ standard library does not have one, but Boost.Range has boost::counting_range, which certainly qualifies. You could also use boost::irange, which is a bit more focused in scope.
C++20's range library will allow you to do this via view::iota(start, end).
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How to printf uint64_t? Fails with: “spurious trailing ‘%’ in format”
I wrote a very simple test code of printf uint64_t:
3 Answers
3
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What's the best way to inverse sort in scala?
...way of changing the sign, if you sort by some numeric value
list.sortBy(- _.size)
More generally, sorting may be done by method sorted with an implicit Ordering, which you may make explicit, and Ordering has a reverse (not the list reverse below)
You can do
list.sorted(theOrdering.reverse)
If...
import module from string variable
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The __import__ function can be a bit hard to understand.
If you change
i = __import__('matplotlib.text')
to
i = __import__('matplotlib.text', fromlist=[''])
then i will refer to matplotlib.text.
In Python 2.7 and Python ...
A gentle tutorial to Emacs/Swank/Paredit for Clojure
...(interactive (list (ido-read-directory-name
"Project root:"
(locate-dominating-file default-directory "pom.xml"))))
(when (get-buffer "*inferior-lisp*")
(kill-buffer "*inferior-lisp*"))
(cd path)
;; I'm not sure if I want to mkdir; doing that wou...
How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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