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How to empty a list in C#?
...end up using = new LisT<T>(); due to the fact that it clears all old allocations instantly. For most people though, .Clear(); will suffice, but if you find a list acting strangely - try using = new List<T>();.
– Charles
Jul 3 '14 at 3:28
...
C++ deprecated conversion from string constant to 'char*'
...lution 2:
char *x = (char *)"foo bar";
Solution 3:
char* x = (char*) malloc(strlen("foo bar")+1); // +1 for the terminator
strcpy(x,"foo bar");
Arrays also can be used instead of pointers because an array is already a constant pointer.
...
Why would I ever use push_back instead of emplace_back?
... the destructor will attempt to call delete on that pointer, which was not allocated by new because it is just a stack object. This leads to undefined behavior.
This is not just invented code. This was a real production bug I encountered. The code was std::vector<T *>, but it owned the conten...
Label Alignment in iOS 6 - UITextAlignment deprecated
...fine ALIGN_CENTER UITextAlignmentCenter
#endif
UILabel* label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 50, 30)];
label.text = @"There is no spoon";
label.textAlignment = ALIGN_CENTER;
[self addSubview:label];
shar...
Is it considered acceptable to not call Dispose() on a TPL Task object?
...l you're doing is using
continuations, that event handle will
never be allocated
...
it's likely better to rely on finalization to take care of things.
Update (Oct 2012)
Stephen Toub has posted a blog titled Do I need to dispose of Tasks? which gives some more detail, and explains the impr...
Java dynamic array sizes?
...
No you can't change the size of an array once created. You either have to allocate it bigger than you think you'll need or accept the overhead of having to reallocate it needs to grow in size. When it does you'll have to allocate a new one and copy the data from the old to the new:
int[] oldItems ...
What are the mechanics of short string optimization in libc++?
... minus 2 bytes to store a short string (i.e. largest capacity() without an allocation).
On a 32 bit machine, 10 chars will fit in the short string. sizeof(string) is 12.
On a 64 bit machine, 22 chars will fit in the short string. sizeof(string) is 24.
A major design goal was to minimize sizeof(...
Adding Core Data to existing iPhone project
...dinator != nil) {
_managedObjectContext = [[NSManagedObjectContext alloc] init];
[_managedObjectContext setPersistentStoreCoordinator:coordinator];
}
return _managedObjectContext;
}
- (NSManagedObjectModel *)managedObjectModel{
if (_managedObjectModel != nil) {
r...
How to get the current date and time
...e();
In the words of the Javadocs for the zero-argument constructor:
Allocates a Date object and initializes it so that it represents the time at which it was allocated, measured to the nearest millisecond.
Make sure you're using java.util.Date and not java.sql.Date -- the latter doesn't hav...
Declaring variables inside or outside of a loop
...ew string in each iteration of the loop, then you could optimize things by allocating the StringBuilder outside the loop. But still, this is not an advisable practice. If you do it without a very good reason, it is a premature optimization.
– Mike Nakis
Jan 11 ...