The NSLog function understands the conventions used by the standard C library printf function, including %f for floats and %d for integers, but in addition uses %@ for objects:
NSLog( @"Prints the UILabel object %@ to the console.", label);
Although NSObject is the most common root class, it is not the only one. For instance, NSProxy is also a root class.
The declaration of properties using the @property compiler directive is a convenience to avoid the declaration and, usually, the implementation of accessor methods for member variables.
When you declare an @property in the class interface, you must also synthesize the property (unless you wish to implement the getter and setter methods yourself) using the @synthesize declaration.
In Objective-C, the nil object is functionally equivalent to the NULL pointer found in many other C-derived languages. However, unlike most of these languages, it is permissible to call methods on nil without causing your application to crash.
NS = Next Step
$ open -h NSSting
NSTimer
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