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What does value & 0xff do in Java?
... that notation? x isn't a number or a hex number?
– Callat
Dec 5 '16 at 18:56
3
@KazRodgers - The...
back button callback in navigationController in iOS
...elegate if it should pop the top UINavigationItem by calling navigationBar(_:shouldPop:). UINavigationController actually implement this, but it doesn't publicly declare that it adopts UINavigationBarDelegate (why!?). To intercept this event, create a subclass of UINavigationController, declare its ...
How to use performSelector:withObject:afterDelay: with primitive types in Cocoa?
The NSObject method performSelector:withObject:afterDelay: allows me to invoke a method on the object with an object argument after a certain time. It cannot be used for methods with a non-object argument (e.g. ints, floats, structs, non-object pointers, etc.).
...
Backwards migration with Django South
Ok, so this seems like a really silly thing to ask, and I'm sure I'm missing something somewhere.
3 Answers
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How to get current time and date in C++?
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In C++ 11 you can use std::chrono::system_clock::now()
Example (copied from en.cppreference.com):
#include <iostream>
#include <chrono>
#include <ctime>
int main()
{
auto start = std::chrono::system_clock::now();
// Some computation ...
How can I initialize base class member variables in derived class constructor?
...ince it would destroy encapsulation. Instead, create a constructor in A to allow B (or any subclass of A) to initialize them:
class A
{
protected:
A(int a, int b) : a(a), b(b) {} // Accessible to derived classes
// Change "protected" to "public" to allow others to instantiate A.
private:
...
Mixin vs inheritance
...
A mixin is typically used with multiple inheritance. So, in that sense, there's "no difference".
The detail is that a mixin is rarely useful as a standalone object.
For example, say you have a mixin named "ColorAndDimension", which adds a co...
Weird PHP error: 'Can't use function return value in write context'
...
You mean
if (isset($_POST['sms_code']) == TRUE ) {
though incidentally you really mean
if (isset($_POST['sms_code'])) {
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improve thi...
What is the default form HTTP method?
...faults to the base URI of the document"
enctype: "The default encoding for all forms is `application/x-www-form-urlencoded'."
<!ATTLIST FORM
ACTION CDATA #IMPLIED
METHOD (%HTTP-Method) GET
ENCTYPE %Content-Type; "application/x-www-form-urlencoded"
...
How to find whether or not a variable is empty in Bash
...variable is undefined and the set -u option (nounset) is activated. Almost all other answers to this question will fail with unbound variable in this case.
– anol
May 26 '15 at 16:29
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