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by tcard 2476 days ago
You can't use jump tables in Objective-C because methods can be added to objects at runtime.
1 comments

That doesn't preclude using jump tables. You can also add methods to objects at runtime in JS and modern runtimes use jump tables.

I expect you can't use jump tables in objc because you can't really "patch in" jump tables at runtime as it's AOT-compiled rather than JIT-ed.

Right, but that's no longer "just" jump tables, you need additional JIT logic for those tables to be correct.

Plus, in a JIT you can go even further and just do direct calls, no need for the indirection of tables.