No: https://www.gnu.org/software/emacs/manual/html_node/elisp/Variable-Scoping.html https://www.gnu.org/software/emacs/manual/html_node/elisp/Va... In practice

No: https://www.gnu.org/software/emacs/manual/html_node/elisp/Variable-Scoping.html https://www.gnu.org/software/emacs/manual/html_node/elisp/Va... In practice, everyone writing new projects uses it, but when you choose to interact with existing code...