I suggest to add a support for generating Objective-C compatible code Swift code for Strings. This would be valuable for mixed Objective-C / Swift projects.

Technical feasibility

To be Objective-C compatible, the template must generate NSObject subclass (instead of Swift enum with proper @objc annotations.

Solving nested classes not being available for Objective-C

Objective-C does not support Swift's nested classes. Only the root class is available in Objective-C by default.
This can be solved by providing custom class name for the nested classes using @objc(ClassName) expression. I suggest using simple namespacing scheme in form of camel-cased chaining of ParentChild class names.

Backwards compatibility

The change would be opt-in only via objcCompatible parameter to template, keeping 100% backwards compatibility with the current version.

Relation to #376

Although this is similar to #376 "Generate ObjC source for .strings files", this suggestion is different. #376 generates Objective-C .h/.m files while this suggestion is to generate Swift code compatible with Objective-C.

I already have the PR ready and will open it as proposal soon. Creating the issue to follow the process and have it as base for discussion.
[EDIT] related PR is #490