Rumor has it that Xcode 4.4 adds support for dictionary, array, and NSNumber literals to Objective-C. It looks like that code just landed in the public clang repo: http://llvm.org/viewvc/llvm-project?view=rev&revision=152137

NSArrays can now be written like @[my, object, collection], NSDictionaries are @{my: object}, NSNumbers are @1(this is a boxed integer, in javaspeak).

NSArrays can now be subscripted with myarray[0], dicts can be subscripted with dict[key].

(See the test cases for example syntax.)
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