Several of us discussed typeof and I'd expect a proposal for a feature along these lines to be well received. (I recall someone even saying they're working on one but that shouldn't stop anyone from submitting one of their own.)
I'm not aware of recent proposals for those but we have discussed ideas along those lines (closures: N2030, C++ lambdas, Apple Blocks: N1451, and I think there was one from Cilk). I think there was interest but not enough support for the details and likely also concerns from implementers.