Where can i find a document explaining how Objective-C is implemented

Question

I mean the fundamental runtime. How is method dispatching implemented (via a selector hashtable?). What is a selector anyway? How is the object model as you can add methods later with some low level API etc.

I need to look at it from a compiler programming point of view, not a simple user of the language.

Answer 1

Here's a few docs to get you started (should help you google the right questions):

• http://www.mulle-kybernetik.com/artikel/Optimization/opti-9.html
• http://developer.apple.com/documentation/Cocoa/Reference/ObjCRuntimeRef/index.html

Answer 2

Use the source, Lothar.

http://www.opensource.apple.com/source/objc4/objc4-437/

And for parsing, look to Clang:

http://clang.llvm.org/get%5Fstarted.html