Swift Technology & Digital Applications 3

Question 1

In Swift, what is a `protocol` with an `associatedtype` primarily used for?

Accepted Answer

Defining generic interfaces that work with placeholder types

Answer

An `associatedtype` acts as a placeholder in a protocol, letting conforming types specify the concrete type, enabling generic protocol-oriented design.

Question 2

Which Swift keyword captures a closure's surrounding variables by value rather than by reference?

Accepted Answer

capture list with `=` syntax

Answer

A capture list entry like `[x = x]` copies the current value of `x` into the closure rather than capturing a reference to it.

Question 3

What does `Task.detached` do differently from `Task` in Swift Concurrency?

Accepted Answer

It creates a task with no actor or priority inheritance

Answer

`Task.detached` creates a task that does not inherit the actor context or priority of the calling scope, unlike a regular `Task`.

Question 4

In Core Data integrated with Swift, what is an `NSManagedObjectContext` responsible for?

Accepted Answer

Acting as a scratch pad for creating, fetching, and saving managed objects

Answer

The `NSManagedObjectContext` is the in-memory workspace where you create, fetch, and modify managed objects before persisting them to the store.

Question 5

Which Combine operator transforms each element from an upstream publisher into a new publisher and flattens the result?

Accepted Answer

flatMap

Answer

`flatMap` transforms each upstream value into a publisher and subscribes to it, emitting the inner publisher's values to downstream.

Swift Practice Test

Swift Practice Test

Swift Technology & Digital Applications 3