Storage Modifiers (Cocoa)
On the Cocoa platform, which uses ARC rather than Garbage Collection for memory management, the three storage modifier keywords strong
, weak
and unretained
are available to control how object references are stored in local variables, fields or properties.
By default, all variables and fields are strong
– that means when an object is
stored in the variable, its retain count is increased, and when a variable's value gets overwritten, the retain count of the previously stored object gets reduced by one.
Read more about this topic in the Storage Modifiers topic in the Cocoa platform section.
var x: weak Button;
Cocoa Only
Storage Modifiers are relevant and available on the Cocoa platform. They can optionally be ignored on .NET, Java and Island, when Cross-Platform Compatibility Mode is enabled.
See Also
- Storage Modifiers in the Cocoa platform section
- Automatic Reference Counting
- Retain Cycles
- Cocoa Platform
- Life-Time Strategies for Island