It looks like a typo in section 4.2 because using (undefined variable) 'c' returns an error on Chibi and Kawa. Otherwise, I fully endorse comments made elsewhere that this is a very accessible and friendly intro to Scheme; thank you! <img width="742" height="648" alt="Image" src="https://github.com/user-attachments/assets/9942900d-7491-4d35-96c0-668e35f26d63" />
It looks like a typo in section 4.2 because using (undefined variable) 'c' returns an error on Chibi and Kawa.
Otherwise, I fully endorse comments made elsewhere that this is a very accessible and friendly intro to Scheme; thank you!