This could be completely off-base but: - Clarity and establishing convention. Boost coroutine2 uses a lot of boostyness to make using coroutines in c++ less pa

This could be completely off-base but: - Clarity and establishing convention. Boost coroutine2 uses a lot of boostyness to make using coroutines in c++ less painful, but they still require boilerplate and can be quite difficult to write. Understanding code that uses coroutine2 also requires understanding how the coroutine2 library works and how it uses normal c++ syntax in unique ways. Having a dedicated operator like [<-] arguably produces more familiar looking and clearer user code. (Take a look at the generator example in the appendix of this proposal; the implementation of the 'generator' type is horrific but the 'Traverse' function is pretty easy to read.) - Generalization. Boost::coroutine2 targets coroutines. This proposal tries to generalize aspects of the coroutines proposal such as the unwrap operator [<-] to support use cases like linear monads.