Swift Intermediate Quiz
Explore classes, structs, protocols, optionals, error handling, and collections
Start the quizSample questions from this quiz
A preview of the style and depth. Try each one, then reveal the answer — or skip straight to the timed quiz.
1. What is a protocol?
- All of the above
- Interface
- Contract
- Blueprint of methods and properties
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Answer: All of the above. Protocol defines requirements: protocol Drawable { func draw() }. Types conform: class Circle: Drawable. Multiple protocols. Protocol-oriented programming. Core Swift paradigm.
2. What is protocol-oriented programming?
- Interface programming
- Protocol design
- Design paradigm using protocols over inheritance
- Contract coding
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Answer: Design paradigm using protocols over inheritance. POP uses protocols and extensions. Composition over inheritance. Protocol extensions provide default implementations. Value types with protocol conformance. Swift philosophy.
3. What is extension?
- Augmentation
- Type extension
- Feature addition
- Adds functionality to existing types
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Answer: Adds functionality to existing types. Extensions add functionality: extension String { func reversed() -> String }. No subclassing needed. Retroactive modeling. Protocol conformance. Very powerful feature.
Frequently asked questions
How many questions are in this Swift quiz?+
30 questions, with a 60-minute time limit. Every question includes a written explanation of the correct answer.
Is this Swift quiz free?+
Yes. Every quiz on CodexQuizz is free and needs no account. You only enter a name if you choose to post your score to the leaderboard.
What level is the intermediate quiz aimed at?+
Explore classes, structs, protocols, optionals, error handling, and collections
Can I use this to prepare for a Swift interview?+
Yes. The questions cover the topics that come up in Swift technical screens, and the explanations are written so that a wrong answer still teaches you the underlying concept.
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