AccessControl.md

Access Control

When do we use it?

Access control is used to restrict parts of your code from code in other files or modules. We use varying access levels to signify intention and availability of code to other developers.

Key Considerations

• Default to private. Anything that can be fully private should be. Use private(set) if you need to access externally, but only allow setting internally.
• Use fileprivate and fileprivate(set) when necessary to restrict access to symbols belonging to a type only to types declared within the same file.
• Never explicitly use internal. It is the default access level, so it never needs to be specified.
• Only use public when a symbol needs to be used outside of its defining module.

Subclassing

• Declare classes as final unless you intend for the type to be subclassed.
• Only declare classes as open when you intend for the type to be subclassed outside of its defining module.

Reference Docs

• Access Control — The Swift Programming Language