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Question: What is the difference between a value type and a reference type in Swift?
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Answer: In Swift, value types are copied when assigned to a new variable or passed as a parameter,
whereas reference types are passed by reference, meaning they share a single instance.
Examples of value types include structs, enums, and basic data types like Int and Bool.
Examples of reference types include classes and closures.
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Question: Can you explain the concept of ARC (Automatic Reference Counting) in Swift?
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Answer: The ARC is a memory management feature in Swift that automatically tracks and manages the lifetime
of objects in your app. It keeps track of how many references to an object exist and deallocates memory for objects
when they are no longer needed.
ARC helps prevent memory leaks and ensures efficient memory usage in Swift apps.
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Question: What is the difference between "let" and "var" in Swift?
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Answer: In Swift, let is used to declare constants whose values cannot be changed once set,
whereas var is used to declare variables whose values can be changed after initialization.
Constants are immutable, meaning their values cannot be reassigned once initialized,
while variables are mutable and can have their values updated.
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Question: What are the different access control levels provided by Swift?
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Answer: Swift provides several access control levels to restrict the access to parts of your code.
These access control levels include open, public, internal, fileprivate, and private.
Please find below their characteristics:
• open and public allow entities to be accessed from outside their defining module
• internal restricts access to within the same module
• fileprivate restricts access to within the same file
• private restricts access to within the same enclosing declaration.
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Question: Can you explain the concept of optional chaining in Swift?
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Answer: The optional chaining in Swift is a mechanism for calling properties, methods, and subscripts
on an optional that might currently be nil.
If the optional contains a value, the property, method, or subscript call succeeds;
if the optional is nil, the entire expression evaluates to nil without causing a runtime error.
Here is an example:
let myOptional: MyClass? = MyClass()
let result = myOptional?.someMethod()
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Question: What are lazy properties in Swift?
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Answer: The lazy properties in Swift are properties that are initialized only when they are first accessed.
They are particularly useful for delaying the initialization of properties until they are actually needed,
which can help improve performance and reduce memory usage, especially for properties that are computationally expensive to initialize.
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