Применим ли принцип Copy-on-write ко всем типам данных и структурами?

The Copy-on-write (COW) principle is not applicable to all data types and structures. It is typically used to optimize operations with mutable objects that initially may share the same memory.

In iOS, COW is applied, for example, to Swift collections (Array, Dictionary, Set), where data is not duplicated immediately upon copying, but only when an attempt is made to modify the copy.

However, for data types that do not support COW or for classes with reference semantics, this principle does not work automatically. In such cases, copying occurs either by reference or a full copy is created.

Thus, COW is an optimization that is selectively applied and depends on the implementation of the specific data type.