One example: https://www.gnu.org/software/emacs/manual/html_node/elisp/Cons-Cells.html https://www.gnu.org/software/emacs/manual/html_node/elisp/Co... The conc

One example: https://www.gnu.org/software/emacs/manual/html_node/elisp/Cons-Cells.html https://www.gnu.org/software/emacs/manual/html_node/elisp/Co... The concept of Lisp through its historic evolution refers to the set of ideas and implementation details that allows one to read a book about Lisp written 40 years ago and apply the same concepts through a language called Lisp today without any -major- changes. If that's not possible or involves substantial programming logic rewriting, the language should not be viewed as Lisp.