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Is the practice of returning a C++ reference variable evil?
...
return i; // DON'T DO THIS.
}
That is all sorts of evil. The stack-allocated i will go away and you are referring to nothing. This is also evil:
int& getInt() {
int* i = new int;
return *i; // DON'T DO THIS.
}
Because now the client has to eventually do the strange:
int&...
What is the overhead of creating a new HttpClient per call in a WebAPI client?
... new HttpClientHandler(); //never dispose this
HttpClient GetClient(string token)
{
//client code can dispose these HttpClient instances
return new HttpClient(_sharedHandler, disposeHandler: false)
{
DefaultRequestHeaders =
{
Authorization = new Authen...
Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
...
[[NSObject]alloc]init] does not equal TRUE or YES. So testing for object initialization with if ([[NSObject]alloc]init]==TRUE) will fail. I've never been comfortable with a Language defining a singular "true" value when in fact any non ...
Why aren't superclass __init__ methods automatically invoked?
...ar (it is called during the creation of a new object, after that object is allocated, to set member variables on the new object), and is almost always the place to implement functionality that in other languages you would put in a constructor. So just call it a constructor!
– B...
Rails params explained?
... seeing that in rails4. For instance, {"_method"=>"put", "authenticity_token"=>"gubHya6uQrQLjPRXhOC0RUuCRdn7NFr6CeKrbRfBSHI=", "ripe"=>"true", "action"=>"update", "controller"=>"apples", "id"=>"4"}. Forgive me if I'm wrong, I'm a rails beginner. According to your note, I should ...
Convert NSDate to NSString
...
How about...
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@"yyyy"];
//Optionally for time zone conversions
[formatter setTimeZone:[NSTimeZone timeZoneWithName:@"..."]];
NSString *stringFromDate = [formatter stringFromDate:myNSDateInstance];
...
When is it right for a constructor to throw an exception?
...and Foo's constructor throws, the language WILL reclaim the memory. If you allocate memory in a constructor and provide no means for releasing it other than the destructor, then the language won't reclaim it if you throw later in the cnostructor. But then, you should have immediately wrapped every a...
How to Rotate a UIImage 90 degrees?
...eImage = [UIImage imageNamed:imgname];
UIImage * portraitImage = [[UIImage alloc] initWithCGImage: landscapeImage.CGImage
scale: 1.0
orientation: UIImageOrientationRight];
Note: As Brainware said th...
What is the default height of UITableViewCell?
...
If you want to calculate this on the fly, just allocate a dummy table cell and read off its height
UITableViewCell *cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"Cell"];
int height = cell.frame.size.height ;
This way you de...
Difference between a Structure and a Union
...e short answer: a struct is a record structure: each element in the struct allocates new space. So, a struct like
struct foobarbazquux_t {
int foo;
long bar;
double baz;
long double quux;
}
allocates at least (sizeof(int)+sizeof(long)+sizeof(double)+sizeof(long double)) bytes in...