Value and reference types

There are some very fundamental differences between value types (structures, enumerations, and tuples) and reference types (classes). The primary difference is how the instances of value and reference types are passed. When we pass an instance of a value type, we are actually passing a copy of the original instance. This means that the changes made to one instance are not reflected back to the others. When we pass an instance of a reference type, we are passing a reference to the original instance. This means that both references point to the same instance; therefore, a change made to one reference will reflect in the others.

The explanation in the previous paragraph is a pretty straightforward explanation; however, ...

Get Swift 4 Protocol-Oriented Programming - Third Edition now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.