what is a defensive copy in Swift ?
Generated on 8/8/2024
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A defensive copy in Swift refers to the practice of creating a copy of a value to ensure that the original value is not inadvertently modified by other parts of the code. This is particularly relevant when dealing with complex data structures or when the storage is in a class property, where it can be challenging for Swift to prove that the property isn't modified simultaneously.
In the context of Swift's performance, defensive copies are sometimes necessary to avoid issues with simultaneous mutations or consumptions of a value. For example, if Swift cannot reliably prove that a property isn't being modified at the same time, it may need to add a defensive copy to ensure data integrity.
For more details, you can refer to the session Explore Swift performance (18:00).
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