+ (let (keep-at-top tail)
+ (if (memq imenu--rescan-item menulist)
+ (setq keep-at-top (cons imenu--rescan-item nil)
+ menulist (delq imenu--rescan-item menulist)))
+ (setq tail menulist)
+ (while tail
+ (if (imenu--subalist-p (car tail))
+ (setq keep-at-top (cons (car tail) keep-at-top)
+ menulist (delq (car tail) menulist)))
+ (setq tail (cdr tail)))
+ (if imenu-sort-function
+ (setq menulist
+ (sort
+ (let ((res nil)
+ (oldlist menulist))
+ ;; Copy list method from the cl package `copy-list'
+ (while (consp oldlist) (push (pop oldlist) res))
+ (if res ; in case, e.g. no functions defined
+ (prog1 (nreverse res) (setcdr res oldlist))))
+ imenu-sort-function)))
+ (if (> (length menulist) imenu-max-items)
+ (let ((count 0))
+ (setq menulist
+ (mapcar
+ (function
+ (lambda (menu)
+ (cons (format "From: %s" (caar menu)) menu)))
+ (imenu--split menulist imenu-max-items)))))
+ (cons title
+ (nconc (nreverse keep-at-top) menulist))))
+
+;;; Split up each long alist that are nested within ALIST
+;;; into nested alists.
+(defun imenu--split-submenus (alist)
+ (mapcar (function
+ (lambda (elt)
+ (if (and (consp elt)
+ (stringp (car elt))
+ (listp (cdr elt)))
+ (imenu--split-menu (cdr elt) (car elt))
+ elt)))
+ alist))
+
+;;; Truncate all strings in MENULIST to imenu-max-item-length
+(defun imenu--truncate-items (menulist)
+ (mapcar (function
+ (lambda (item)
+ (cond
+ ((consp (cdr item))
+ (imenu--truncate-items (cdr item)))
+ (t
+ ;; truncate if necessary
+ (if (and (numberp imenu-max-item-length)
+ (> (length (car item)) imenu-max-item-length))
+ (setcar item (substring (car item) 0 imenu-max-item-length)))))))
+ menulist))