;;; gnus-range.el --- range and sequence functions for Gnus
-;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
-;; 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+;; Copyright (C) 1996-2012 Free Software Foundation, Inc.
;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
;; Keywords: news
(defun gnus-set-difference (list1 list2)
"Return a list of elements of LIST1 that do not appear in LIST2."
- (let ((list1 (copy-sequence list1)))
- (while list2
- (setq list1 (delq (car list2) list1))
- (setq list2 (cdr list2)))
- list1))
+ (let ((hash2 (make-hash-table :test 'eq))
+ (result nil))
+ (dolist (elt list2) (puthash elt t hash2))
+ (dolist (elt list1)
+ (unless (gethash elt hash2)
+ (setq result (cons elt result))))
+ (nreverse result)))
+
+(defun gnus-range-nconcat (&rest ranges)
+ "Return a range comprising all the RANGES, which are pre-sorted.
+RANGES will be destructively altered."
+ (setq ranges (delete nil ranges))
+ (let* ((result (gnus-range-normalize (pop ranges)))
+ (last (last result)))
+ (dolist (range ranges)
+ (setq range (gnus-range-normalize range))
+ ;; Normalize the single-number case, so that we don't need to
+ ;; special-case that so much.
+ (when (numberp (car last))
+ (setcar last (cons (car last) (car last))))
+ (when (numberp (car range))
+ (setcar range (cons (car range) (car range))))
+ (if (= (1+ (cdar last)) (caar range))
+ (progn
+ (setcdr (car last) (cdar range))
+ (setcdr last (cdr range)))
+ (setcdr last range)
+ ;; Denormalize back, since we couldn't join the ranges up.
+ (when (= (caar range) (cdar range))
+ (setcar range (caar range)))
+ (when (= (caar last) (cdar last))
+ (setcar last (caar last))))
+ (setq last (last last)))
+ (if (and (consp (car result))
+ (= (length result) 1))
+ (car result)
+ result)))
(defun gnus-range-difference (range1 range2)
"Return the range of elements in RANGE1 that do not appear in RANGE2.
;; All done with range2
(setq r nil))
((< max1 min2)
- ;; No overlap: range1 preceeds range2
+ ;; No overlap: range1 precedes range2
(pop r))
((< max2 min1)
- ;; No overlap: range2 preceeds range1
+ ;; No overlap: range2 precedes range1
(pop range2))
((and (<= min2 min1) (<= max1 max2))
;; Complete overlap: range1 removed
RANGE1 and RANGE2 have to be sorted over <."
(let* (out
(min1 (car range1))
- (max1 (if (numberp min1)
+ (max1 (if (numberp min1)
(if (numberp (cdr range1))
(prog1 (cdr range1)
(setq range1 nil)) min1)
(min2 (car range2))
(max2 (if (numberp min2)
(if (numberp (cdr range2))
- (prog1 (cdr range2)
- (setq range2 nil)) min2)
+ (prog1 (cdr range2)
+ (setq range2 nil)) min2)
(prog1 (cdr min2)
(setq min2 (car min2))))))
(setq range1 (cdr range1)
range2 (cdr range2))
(while (and min1 min2)
- (cond ((< max1 min2) ; range1 preceeds range2
+ (cond ((< max1 min2) ; range1 precedes range2
(setq range1 (cdr range1)
min1 nil))
- ((< max2 min1) ; range2 preceeds range1
+ ((< max2 min1) ; range2 precedes range1
(setq range2 (cdr range2)
min2 nil))
(t ; some sort of overlap is occurring
(setq sum
(+ sum (if (consp x) (- (cdr x) (car x) -1) 1))))))))
-(defun gnus-sublist-p (list sublist)
- "Test whether all elements in SUBLIST are members of LIST."
- (let ((sublistp t))
- (while sublist
- (unless (memq (pop sublist) list)
- (setq sublistp nil
- sublist nil)))
- sublistp))
-
(defun gnus-range-add (range1 range2)
"Add RANGE2 to RANGE1 (nondestructively)."
(unless (listp (cdr range1))
(provide 'gnus-range)
-;; arch-tag: 4780bdd8-5a15-4aff-be28-18727895b6ad
;;; gnus-range.el ends here