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Why can I not push_back a unique_ptr into a vector?
... guarantees that a single unique_ptr container has ownership of the held pointer. This means that you can't make copies of a unique_ptr (because then two unique_ptrs would have ownership), so you can only move it.
Note, however, that your current use of unique_ptr is incorrect. You cannot use it ...
Possible to iterate backwards through a foreach?
...also an essential part of modern iterator-based programming. Perhaps the point is that it would be clearer/safer if there were two distinct keywords, to clarify whether one is asserting that the iterations are order-independent? [Given a language like Eiffel that can propagate contracts, such assert...
Differences in boolean operators: & vs && and | vs ||
...
Those are the bitwise AND and bitwise OR operators.
int a = 6; // 110
int b = 4; // 100
// Bitwise AND
int c = a & b;
// 110
// & 100
// -----
// 100
// Bitwise OR
int d = a | b;
// 110
// | 100
// -----
// 110
System.out.println(c); // 4
System.out.pr...
What's the best way to store co-ordinates (longitude/latitude, from Google Maps) in SQL Server?
...T NULL,
[GeographyPoint] AS ([geography]::STGeomFromText(((('POINT('+CONVERT([varchar](20),[Longitude]))+' ')+CONVERT([varchar](20),[Latitude]))+')',(4326)))
)
This gives you the flexibility of spatial queries on the geoPoint column and you can also retrieve the latitude and longitude value...
Static variables in member functions
...A::foo() is a non-template function. There will be only one copy of static int i inside the program.
Any instance of A object will affect the same i and lifetime of i will remain through out the program. To add an example:
A o1, o2, o3;
o1.foo(); // i = 1
o2.foo(); // i = 2
o3.foo(); // i = 3
o1.f...
C# 3.0 auto-properties — useful or not? [closed]
...code? If you want to do stuff in getters or setters, there's no problem to convert them to normal properties later on.
As you said you could use fields, and if you wanted to add logic to them later you'd convert them to properties. But this might present problems with any use of reflection (and pos...
How do I get the height and width of the Android Navigation Bar programmatically?
...
Try below code:
Resources resources = context.getResources();
int resourceId = resources.getIdentifier("navigation_bar_height", "dimen", "android");
if (resourceId > 0) {
return resources.getDimensionPixelSize(resourceId);
}
return 0;
...
What is the most efficient Java Collections library? [closed]
...
I've worked on quite a few data intensive projects where collections were a huge bottleneck. Java Collections are terribly inefficient (both memory and speed) especially if they store primitives.
– Jay Askren
Sep 25 '...
How to check if all list items have the same value and return it, or return an “otherValue” if they
...ts, see this question. In that cases, you need to implement the IEquatable interface.
– Matt
May 14 '14 at 14:46
...
How to see if an object is an array without using reflection?
...esult is false.
That means you can do something like this:
Object o = new int[] { 1,2 };
System.out.println(o instanceof int[]); // prints "true"
You'd have to check if the object is an instanceof boolean[], byte[], short[], char[], int[], long[], float[], double[], or Object[], if you wan...