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Is it better to call ToList() or ToArray() in LINQ queries?
...straints you should use ToList. In the majority of scenarios ToArray will allocate more memory than ToList.
Both use arrays for storage, but ToList has a more flexible constraint. It needs the array to be at least as large as the number of elements in the collection. If the array is larger, th...
How to intercept touches events on a MKMapView or UIWebView objects?
...
WildcardGestureRecognizer * tapInterceptor = [[WildcardGestureRecognizer alloc] init];
tapInterceptor.touchesBeganCallback = ^(NSSet * touches, UIEvent * event) {
self.lockedOnUserLocation = NO;
};
[mapView addGestureRecognizer:tapInterceptor];
WildcardGestureRecognizer.h
//
// Wildcar...
How to allocate aligned memory only using the standard library?
...
Original answer
{
void *mem = malloc(1024+16);
void *ptr = ((char *)mem+16) & ~ 0x0F;
memset_16aligned(ptr, 0, 1024);
free(mem);
}
Fixed answer
{
void *mem = malloc(1024+15);
void *ptr = ((uintptr_t)mem+15) & ~ (uintptr_t)0x0...
C++ Object Instantiation
...
On the contrary, you should always prefer stack allocations, to the extent that as a rule of thumb, you should never have new/delete in your user code.
As you say, when the variable is declared on the stack, its destructor is automatically called when it goes out of scope...
Java's Virtual Machine and CLR
...ed into "AppDomains", providing sub-application-level sandboxes for memory allocation and code execution).
The CLR bytecode format (composed of MSIL instructions and metadata) has fewer instruction types than the JVM. In the JVM, every unique operation (add two int values, add two float values, etc)...
Why use double indirection? or Why use pointers to pointers?
...****biolibrary;
char ******lol;
//fill data structure
word = malloc(4 * sizeof *word); // assume it worked
strcpy(word, "foo");
sentence = malloc(4 * sizeof *sentence); // assume it worked
sentence[0] = word;
sentence[1] = word;
sentence[2] = word;
sentence[3] =...
get NSDate today, yesterday, this Week, last Week, this Month, last Month… variables
...UnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond ) fromDate:[[NSDate alloc] init]];
[components setHour:-[components hour]];
[components setMinute:-[components minute]];
[components setSecond:-[components second]];
NSDate *today = [cal dateByAddingComponents:components toDate:[[NSDate alloc] ...
Setting direction for UISwipeGestureRecognizer
...
UISwipeGestureRecognizer *swipeLeftRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleGesture:)];
[swipeLeftRight setDirection:(UISwipeGestureRecognizerDirectionRight | UISwipeGestureRecognizerDirectionLeft )];
[self.view addGestureRecognizer:swipeLeftR...
Execute a terminal command from a Cocoa app
...;
NSFileHandle *file = pipe.fileHandleForReading;
NSTask *task = [[NSTask alloc] init];
task.launchPath = @"/usr/bin/grep";
task.arguments = @[@"foo", @"bar.txt"];
task.standardOutput = pipe;
[task launch];
NSData *data = [file readDataToEndOfFile];
[file closeFile];
NSString *grepOutput = [[NSS...
How to add a right button to a UINavigationController?
...[super viewDidLoad];
UIBarButtonItem *anotherButton = [[UIBarButtonItem alloc] initWithTitle:@"Show" style:UIBarButtonItemStylePlain target:self action:@selector(refreshPropertyList:)];
self.navigationItem.rightBarButtonItem = anotherButton;
// exclude the following in ARC projects....