What are immutable data structures and how do they affect performance?

What are immutable data structures and how do they affect performance?

Immutable data structures are data types that cannot be modified after they are created. This means any change results in a new data structure being created. They can improve performance in certain scenarios, especially in functional programming, by enabling easier reasoning about code and reducing bugs.

Can you give me an example of an immutable data structure?

Sure! A common example is a string in many programming languages. Once a string is created, it cannot be changed. If you want to modify it, a new string is created instead.

What are the performance benefits of using immutable data structures?

The main benefits include easier concurrency, as immutable structures can be shared safely between threads, and reduced memory overhead due to structural sharing, where new versions of data structures can reuse parts of the old ones.

Are there any downsides to using immutable data structures?

Yes, one downside is that they can lead to increased memory usage if not managed properly, as each modification creates a new instance. Additionally, they may introduce performance overhead in scenarios where frequent updates are required.