Swift · Interview Question

When do you need to mark a method as `mutating` inside a Swift struct?

Detailed answer, explanation and code for this interview question. Ideal for Swift interview preparation, coding rounds and viva questions.

Difficulty: MediumType: MCQ

Problem Statement

Explanation

In Swift a `struct` is a value type. To modify its own properties within a method, you must mark the method `mutating`. This makes clear that the instance is being changed. Classes do not require `mutating`.

Practice Sets

This question appears in the following practice sets:

Structs, Classes & Value vs Reference Types

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When do you need to mark a method as `mutating` inside a Swift struct?

Problem Statement

Explanation

Practice Sets

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When do you need to mark a method as `mutating` inside a Swift struct?

Problem Statement

Explanation

Practice Sets

Related Questions

What is the difference between `let` and `var` in Swift?

What does the `?` after a type name signify in Swift, e.g., `Int?`?

Which statement is true about `struct` vs `class` in Swift?

What is the purpose of a `guard` statement in Swift?

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More from Swift

When do you need to mark a method as `mutating` inside a Swift struct?

Problem Statement

Explanation

Practice Sets

Related Questions

What is the difference between `let` and `var` in Swift?

What does the `?` after a type name signify in Swift, e.g., `Int?`?

Which statement is true about `struct` vs `class` in Swift?

What is the purpose of a `guard` statement in Swift?

Which of these best describes a closure in Swift?

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Master Interviews Anywhere, Anytime

When do you need to mark a method as `mutating` inside a Swift struct?

Problem Statement

Explanation

Practice Sets

Related Questions

What is the difference between `let` and `var` in Swift?

What does the `?` after a type name signify in Swift, e.g., `Int?`?

Which statement is true about `struct` vs `class` in Swift?

What is the purpose of a `guard` statement in Swift?

Which of these best describes a closure in Swift?

More from Swift

Master Interviews
Anywhere, Anytime