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What is “rvalue reference for *this”?
Came across a proposal called "rvalue reference for *this" in clang's C++11 status page .
3 Answers
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How can I remove all objects but one from the workspace in R?
I have a workspace with lots of objects and I would like to remove all but one. Ideally I would like to avoid having to type rm(obj.1, obj.2... obj.n) . Is it possible to indicate remove all objects but these ones ?
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How do you format an unsigned long long int using printf?
...want to try using the inttypes.h library that gives you types such as
int32_t, int64_t, uint64_t etc.
You can then use its macros such as:
uint64_t x;
uint32_t y;
printf("x: %"PRId64", y: %"PRId32"\n", x, y);
This is "guaranteed" to not give you the same trouble as long, unsigned long long etc, ...
How to execute a Python script from the Django shell?
...es, it's a good idea to set it up as a custom command ie
$ ./manage.py my_command
to do this create a file in a subdir of management and commands of your app, ie
my_app/
__init__.py
models.py
management/
__init__.py
commands/
__init__.py
my_co...
Convert a float64 to an int in Go
...problem in Go that can be unexpected (at least if you come from Java): "In all non-constant conversions involving floating-point or complex values, if the result type cannot represent the value the conversion succeeds but the result value is implementation-dependent." (golang.org/ref/spec#Conversion...
How can I determine whether a 2D Point is within a Polygon?
...integers. Many systems use integers for UI painting (pixels are ints after all), but macOS for example uses float for everything. macOS only knows points and a point can translate to one pixel, but depending on monitor resolution, it might translate to something else. On retina screens half a point ...
How to enumerate an enum with String type?
...h Xcode 10), just add protocol conformance to CaseIterable to benefit from allCases. To add this protocol conformance, you simply need to write somewhere:
extension Suit: CaseIterable {}
If the enum is your own, you may specify the conformance directly in the declaration:
enum Suit: String, CaseIte...
Visual Studio support for new C / C++ standards?
I keep reading about C99 and C++11 and all these totally sweet things that are getting added to the language standard that might be nice to use someday. However, we currently languish in the land of writing C++ in Visual Studio.
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PHP Get Site URL Protocol - http vs https
...olutions are quite messy; this is how I would do it:
$protocol = stripos($_SERVER['SERVER_PROTOCOL'],'https') === 0 ? 'https://' : 'http://';
...or even without condition if you prefer:
$protocol = strtolower(substr($_SERVER["SERVER_PROTOCOL"],0,strpos( $_SERVER["SERVER_PROTOCOL"],'/'))).'://';
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How to detect shake event with android?
...CCELEROMETER) {
long curTime = System.currentTimeMillis();
// only allow one update every 100ms.
if ((curTime - lastUpdate) > 100) {
long diffTime = (curTime - lastUpdate);
lastUpdate = curTime;
x = values[SensorManager.DATA_X];
y = values[SensorManager.DATA_Y...