Certainly adding call/cc doesn't allow you to represent more computable functions by programs. But there are plenty of internal features of programs that we're

Certainly adding call/cc doesn't allow you to represent more computable functions by programs. But there are plenty of internal features of programs that we're interested in, that let us meaningfully distinguish amongst programs that otherwise have the exact same observable behavior. I like coroutines as an example here, because I have very direct experience writing programs with similar behavior in systems that either do or do not have coroutines. By far, I found the coroutine-based programs far easier to understand and extend. Mattias Felleisen wrote the seminal paper on comparing expressive power of Turing-complete languages. It's worth a read if it's not come across your radar before! https://homepage.cs.uiowa.edu/~jgmorrs/eecs762f19/papers/felleisen.pdf https://homepage.cs.uiowa.edu/~jgmorrs/eecs762f19/papers/fel... Although, Shriram Krishnamurthi's talk from two years ago on this paper might be more approachable. https://www.youtube.com/watch?v=43XaZEn2aLc https://www.youtube.com/watch?v=43XaZEn2aLc