;; NOTE: https://github.com/minad/tempel/issues/23

c-mode c-ts-mode c++-mode c++-ts-mode

(guard
 "#ifndef "
 (p
  (thread-last
    (file-name-base (or (buffer-file-name)
                        (buffer-name)))
    (concat (when-let ((project (project-current)))
              (concat (project-name project) "_")))
    (upcase)
    (string-replace "-" "_")
    (replace-regexp-in-string "^[0-9]+" "_\\&")
    (replace-regexp-in-string "[^A-Z0-9_]+" "")
    (format "%s_H"))
  header)
 n
 "#define " header n n r n n
 "#endif /* !" header " */")

emacs-lisp-mode

(header
 ";;; " (file-name-nondirectory (or (buffer-file-name)
                                    (buffer-name)))
 " --- " p "  -*- lexical-binding: t; -*-" n n q)

(section "\f" n ";;; " p n n q)