Function: backquote-listify

backquote-listify is a byte-compiled function defined in backquote.el.gz.

Signature

(backquote-listify LIST OLD-TAIL)

Source Code

;; Defined in /usr/src/emacs/lisp/emacs-lisp/backquote.el.gz
;; backquote-listify takes (tag . structure) pairs from backquote-process
;; and decides between append, list, backquote-list*, and cons depending
;; on which tags are in the list.

(defun backquote-listify (list old-tail)
  (let ((heads nil) (tail (cdr old-tail)) (list-tail list) (item nil))
    (if (= (car old-tail) 0)
	(setq tail (eval tail)
	      old-tail nil))
    (while (consp list-tail)
      (setq item (car list-tail))
      (setq list-tail (cdr list-tail))
      (if (or heads old-tail (/= (car item) 0))
	  (setq heads (cons (cdr item) heads))
	(setq tail (cons (eval (cdr item)) tail))))
    (cond
     (tail
      (if (null old-tail)
	  (setq tail (list 'quote tail)))
      (if heads
	  (let ((use-list* (or (cdr heads)
			       (and (consp (car heads))
				    (eq (car (car heads))
					backquote-splice-symbol)))))
	    (cons (if use-list* 'backquote-list* 'cons)
		  (append heads (list tail))))
	tail))
     (t (cons 'list heads)))))