What is Objective-C run time?
The Objective-C runtime is a runtime library that provides support for the dynamic properties of the Objective-C language, and as such is linked to by all Objective-C apps. Objective-C runtime library support functions are implemented in the shared library found at /usr/lib/libobjc.
Is it faster to iterate through an NSArray or an NSSet?
Yes, NSArray is faster than NSSet for simply holding and iterating. As little as 50% faster for constructing and as much as 500% faster for iterating.
Does NSDictionary retain objects?
Usually NSDictionary copies its keys. When using a shared key set it will instead reuse those objects, which saves memory.
What is NSMutableArray Objective-C?
The NSMutableArray class declares the programmatic interface to objects that manage a modifiable array of objects. This class adds insertion and deletion operations to the basic array-handling behavior inherited from NSArray . NSMutableArray is “toll-free bridged” with its Core Foundation counterpart, CFMutableArray .
What is swift runtime?
The Swift runtime exports standard metadata objects for Builtin types as well as standard value witness tables that can be freely adopted by types with common layout attributes.
What is NSSet in Swift?
NSSet is “toll-free bridged” with its Core Foundation counterpart, CFSet . See Toll-Free Bridging for more information on toll-free bridging. In Swift, use this class instead of a Set constant in cases where you require reference semantics.
How do I create an NSDictionary in Objective-C?
Objective-C Language NSDictionary
- Create# NSDictionary *dict = [[NSDictionary alloc] initWithObjectsAndKeys:@”value1″, @”key1″, @”value2″, @”key2″, nil];
- NSDictionary to NSArray.
- NSDictionary to NSData.
- NSDictionary to JSON.
- Block Based Enumeration.
- Fast Enumeration.
What is a NSDictionary object?
An object representing a static collection of key-value pairs, for use instead of a Dictionary constant in cases that require reference semantics.
What is difference between NSArray and NSMutableArray?
The primary difference between NSArray and NSMutableArray is that a mutable array can be changed/modified after it has been allocated and initialized, whereas an immutable array, NSArray , cannot.
Is C++ better than Objective-C?
In my opinion, probably the biggest difference is the syntax. You can achieve essentially the same things in either language, but in my opinion the C++ syntax is simpler while some of Objective-C’s features make certain tasks (such as GUI design) easier thanks to dynamic dispatch.
What is the Objective-C runtime library?
The Objective-C runtime is a runtime library that provides support for the dynamic properties of the Objective-C language, and as such is linked to by all Objective-C apps. Objective-C runtime library support functions are implemented in the shared library found at /usr/lib/libobjc.A.dylib. You typically don’t need to use
What does method return do in Objective-C?
Returns a method description structure for a specified method. Sets the implementation of a method. Exchanges the implementations of two methods. Returns the names of all the loaded Objective-C frameworks and dynamic libraries. func class_getImageName(AnyClass?) -> UnsafePointer?
What is an opaque data type in Objective C?
An opaque type that represents a category. An opaque type that represents an Objective-C declared property. Defines an Objective-C method. Defines a property attribute. These are the data types that represent objects, classes, and superclasses.
What does objc_setenumerationmutationhandler do?
Inserted by the compiler when a mutation is detected during a foreach iteration. func objc_setEnumerationMutationHandler( ( (Any) -> Void)?) Sets the current mutation handler. Creates a pointer to a function that calls the specified block when the method is called.