lisp/gnus/gnus-range.el

   1 ;;; gnus-range.el --- range and sequence functions for Gnus
   2
   3 ;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
   5
   6 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   7 ;; Keywords: news
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;;; Code:
  27
  28 (eval-when-compile (require 'cl))
  29
  30 ;;; List and range functions
  31
  32 (defsubst gnus-range-normalize (range)
  33   "Normalize RANGE.
  34 If RANGE is a single range, return (RANGE). Otherwise, return RANGE."
  35   (if (listp (cdr-safe range)) range (list range)))
  36
  37 (defun gnus-last-element (list)
  38   "Return last element of LIST."
  39   (while (cdr list)
  40     (setq list (cdr list)))
  41   (car list))
  42
  43 (defun gnus-copy-sequence (list)
  44   "Do a complete, total copy of a list."
  45   (let (out)
  46     (while (consp list)
  47       (if (consp (car list))
  48           (push (gnus-copy-sequence (pop list)) out)
  49         (push (pop list) out)))
  50     (if list
  51         (nconc (nreverse out) list)
  52       (nreverse out))))
  53
  54 (defun gnus-set-difference (list1 list2)
  55   "Return a list of elements of LIST1 that do not appear in LIST2."
  56   (let ((list1 (copy-sequence list1)))
  57     (while list2
  58       (setq list1 (delq (car list2) list1))
  59       (setq list2 (cdr list2)))
  60     list1))
  61
  62 (defun gnus-range-difference (range1 range2)
  63   "Return the range of elements in RANGE1 that do not appear in RANGE2.
  64 Both ranges must be in ascending order."
  65   (setq range1 (gnus-range-normalize range1))
  66   (setq range2 (gnus-range-normalize range2))
  67   (let* ((new-range (cons nil (copy-sequence range1)))
  68          (r new-range)
  69          (safe t))
  70     (while (cdr r)
  71       (let* ((r1 (cadr r))
  72              (r2 (car range2))
  73              (min1 (if (numberp r1) r1 (car r1)))
  74              (max1 (if (numberp r1) r1 (cdr r1)))
  75              (min2 (if (numberp r2) r2 (car r2)))
  76              (max2 (if (numberp r2) r2 (cdr r2))))
  77
  78         (cond ((> min1 max1)
  79                ;; Invalid range: may result from overlap condition (below)
  80                ;; remove Invalid range
  81                (setcdr r (cddr r)))
  82               ((and (= min1 max1)
  83                     (listp r1))
  84                ;; Inefficient representation: may result from overlap condition (below)
  85                (setcar (cdr r) min1))
  86               ((not min2)
  87                ;; All done with range2
  88                (setq r nil))
  89               ((< max1 min2)
  90                ;; No overlap: range1 preceeds range2
  91                (pop r))
  92               ((< max2 min1)
  93                ;; No overlap: range2 preceeds range1
  94                (pop range2))
  95               ((and (<= min2 min1) (<= max1 max2))
  96                ;; Complete overlap: range1 removed
  97                (setcdr r (cddr r)))
  98               (t
  99                (setcdr r (nconc (list (cons min1 (1- min2)) (cons (1+ max2) max1)) (cddr r)))))))
 100     (cdr new-range)))
 101
 102
 103
 104 ;;;###autoload
 105 (defun gnus-sorted-difference (list1 list2)
 106   "Return a list of elements of LIST1 that do not appear in LIST2.
 107 Both lists have to be sorted over <.
 108 The tail of LIST1 is not copied."
 109   (let (out)
 110     (while (and list1 list2)
 111       (cond ((= (car list1) (car list2))
 112              (setq list1 (cdr list1)
 113                    list2 (cdr list2)))
 114             ((< (car list1) (car list2))
 115              (setq out (cons (car list1) out))
 116              (setq list1 (cdr list1)))
 117             (t
 118              (setq list2 (cdr list2)))))
 119     (nconc (nreverse out) list1)))
 120
 121 ;;;###autoload
 122 (defun gnus-sorted-ndifference (list1 list2)
 123   "Return a list of elements of LIST1 that do not appear in LIST2.
 124 Both lists have to be sorted over <.
 125 LIST1 is modified."
 126   (let* ((top (cons nil list1))
 127          (prev top))
 128     (while (and list1 list2)
 129       (cond ((= (car list1) (car list2))
 130              (setcdr prev (cdr list1))
 131              (setq list1 (cdr list1)
 132                    list2 (cdr list2)))
 133             ((< (car list1) (car list2))
 134              (setq prev list1
 135                    list1 (cdr list1)))
 136             (t
 137              (setq list2 (cdr list2)))))
 138     (cdr top)))
 139
 140 ;;;###autoload
 141 (defun gnus-sorted-complement (list1 list2)
 142   "Return a list of elements that are in LIST1 or LIST2 but not both.
 143 Both lists have to be sorted over <."
 144   (let (out)
 145     (if (or (null list1) (null list2))
 146         (or list1 list2)
 147       (while (and list1 list2)
 148         (cond ((= (car list1) (car list2))
 149                (setq list1 (cdr list1)
 150                      list2 (cdr list2)))
 151               ((< (car list1) (car list2))
 152                (setq out (cons (car list1) out))
 153                (setq list1 (cdr list1)))
 154               (t
 155                (setq out (cons (car list2) out))
 156                (setq list2 (cdr list2)))))
 157       (nconc (nreverse out) (or list1 list2)))))
 158
 159 ;;;###autoload
 160 (defun gnus-intersection (list1 list2)
 161   (let ((result nil))
 162     (while list2
 163       (when (memq (car list2) list1)
 164         (setq result (cons (car list2) result)))
 165       (setq list2 (cdr list2)))
 166     result))
 167
 168 ;;;###autoload
 169 (defun gnus-sorted-intersection (list1 list2)
 170   "Return intersection of LIST1 and LIST2.
 171 LIST1 and LIST2 have to be sorted over <."
 172   (let (out)
 173     (while (and list1 list2)
 174       (cond ((= (car list1) (car list2))
 175              (setq out (cons (car list1) out)
 176                    list1 (cdr list1)
 177                    list2 (cdr list2)))
 178             ((< (car list1) (car list2))
 179              (setq list1 (cdr list1)))
 180             (t
 181              (setq list2 (cdr list2)))))
 182     (nreverse out)))
 183
 184 ;;;###autoload
 185 (defun gnus-sorted-range-intersection (range1 range2)
 186   "Return intersection of RANGE1 and RANGE2.
 187 RANGE1 and RANGE2 have to be sorted over <."
 188   (let* (out
 189          (min1 (car range1))
 190          (max1 (if (numberp min1)
 191                    (if (numberp (cdr range1))
 192                        (prog1 (cdr range1)
 193                          (setq range1 nil)) min1)
 194                  (prog1 (cdr min1)
 195                    (setq min1 (car min1)))))
 196          (min2 (car range2))
 197          (max2 (if (numberp min2)
 198                    (if (numberp (cdr range2))
 199                        (prog1 (cdr range2)
 200                          (setq range2 nil)) min2)
 201                  (prog1 (cdr min2)
 202                    (setq min2 (car min2))))))
 203     (setq range1 (cdr range1)
 204           range2 (cdr range2))
 205     (while (and min1 min2)
 206       (cond ((< max1 min2)              ; range1 preceeds range2
 207              (setq range1 (cdr range1)
 208                    min1 nil))
 209             ((< max2 min1)              ; range2 preceeds range1
 210              (setq range2 (cdr range2)
 211                    min2 nil))
 212             (t                     ; some sort of overlap is occurring
 213              (let ((min (max min1 min2))
 214                    (max (min max1 max2)))
 215                (setq out (if (= min max)
 216                              (cons min out)
 217                            (cons (cons min max) out))))
 218              (if (< max1 max2)          ; range1 ends before range2
 219                  (setq min1 nil)        ; incr range1
 220                (setq min2 nil))))       ; incr range2
 221       (unless min1
 222         (setq min1 (car range1)
 223               max1 (if (numberp min1) min1 (prog1 (cdr min1) (setq min1 (car min1))))
 224               range1 (cdr range1)))
 225       (unless min2
 226         (setq min2 (car range2)
 227               max2 (if (numberp min2) min2 (prog1 (cdr min2) (setq min2 (car min2))))
 228               range2 (cdr range2))))
 229     (cond ((cdr out)
 230         (nreverse out))
 231           ((numberp (car out))
 232            out)
 233           (t
 234            (car out)))))
 235
 236 ;;;###autoload
 237 (defalias 'gnus-set-sorted-intersection 'gnus-sorted-nintersection)
 238
 239 ;;;###autoload
 240 (defun gnus-sorted-nintersection (list1 list2)
 241   "Return intersection of LIST1 and LIST2 by modifying cdr pointers of LIST1.
 242 LIST1 and LIST2 have to be sorted over <."
 243   (let* ((top (cons nil list1))
 244          (prev top))
 245     (while (and list1 list2)
 246       (cond ((= (car list1) (car list2))
 247              (setq prev list1
 248                    list1 (cdr list1)
 249                    list2 (cdr list2)))
 250             ((< (car list1) (car list2))
 251              (setcdr prev (cdr list1))
 252              (setq list1 (cdr list1)))
 253             (t
 254              (setq list2 (cdr list2)))))
 255     (setcdr prev nil)
 256     (cdr top)))
 257
 258 ;;;###autoload
 259 (defun gnus-sorted-union (list1 list2)
 260   "Return union of LIST1 and LIST2.
 261 LIST1 and LIST2 have to be sorted over <."
 262   (let (out)
 263     (while (and list1 list2)
 264       (cond ((= (car list1) (car list2))
 265              (setq out (cons (car list1) out)
 266                    list1 (cdr list1)
 267                    list2 (cdr list2)))
 268             ((< (car list1) (car list2))
 269              (setq out (cons (car list1) out)
 270                    list1 (cdr list1)))
 271             (t
 272              (setq out (cons (car list2) out)
 273                    list2 (cdr list2)))))
 274     (while list1
 275       (setq out (cons (car list1) out)
 276             list1 (cdr list1)))
 277     (while list2
 278       (setq out (cons (car list2) out)
 279             list2 (cdr list2)))
 280     (nreverse out)))
 281
 282 ;;;###autoload
 283 (defun gnus-sorted-nunion (list1 list2)
 284   "Return union of LIST1 and LIST2 by modifying cdr pointers of LIST1.
 285 LIST1 and LIST2 have to be sorted over <."
 286   (let* ((top (cons nil list1))
 287          (prev top))
 288     (while (and list1 list2)
 289       (cond ((= (car list1) (car list2))
 290              (setq prev list1
 291                    list1 (cdr list1)
 292                    list2 (cdr list2)))
 293             ((< (car list1) (car list2))
 294              (setq prev list1
 295                    list1 (cdr list1)))
 296             (t
 297              (setcdr prev (list (car list2)))
 298              (setq prev (cdr prev)
 299                    list2 (cdr list2))
 300              (setcdr prev list1))))
 301     (while list2
 302       (setcdr prev (list (car list2)))
 303       (setq prev (cdr prev)
 304             list2 (cdr list2)))
 305     (cdr top)))
 306
 307 (defun gnus-compress-sequence (numbers &optional always-list)
 308   "Convert sorted list of numbers to a list of ranges or a single range.
 309 If ALWAYS-LIST is non-nil, this function will always release a list of
 310 ranges."
 311   (let* ((first (car numbers))
 312          (last (car numbers))
 313          result)
 314     (if (null numbers)
 315         nil
 316       (if (not (listp (cdr numbers)))
 317           numbers
 318         (while numbers
 319           (cond ((= last (car numbers)) nil) ;Omit duplicated number
 320                 ((= (1+ last) (car numbers)) ;Still in sequence
 321                  (setq last (car numbers)))
 322                 (t                      ;End of one sequence
 323                  (setq result
 324                        (cons (if (= first last) first
 325                                (cons first last))
 326                              result))
 327                  (setq first (car numbers))
 328                  (setq last  (car numbers))))
 329           (setq numbers (cdr numbers)))
 330         (if (and (not always-list) (null result))
 331             (if (= first last) (list first) (cons first last))
 332           (nreverse (cons (if (= first last) first (cons first last))
 333                           result)))))))
 334
 335 (defalias 'gnus-uncompress-sequence 'gnus-uncompress-range)
 336 (defun gnus-uncompress-range (ranges)
 337   "Expand a list of ranges into a list of numbers.
 338 RANGES is either a single range on the form `(num . num)' or a list of
 339 these ranges."
 340   (let (first last result)
 341     (cond
 342      ((null ranges)
 343       nil)
 344      ((not (listp (cdr ranges)))
 345       (setq first (car ranges))
 346       (setq last (cdr ranges))
 347       (while (<= first last)
 348         (setq result (cons first result))
 349         (setq first (1+ first)))
 350       (nreverse result))
 351      (t
 352       (while ranges
 353         (if (atom (car ranges))
 354             (when (numberp (car ranges))
 355               (setq result (cons (car ranges) result)))
 356           (setq first (caar ranges))
 357           (setq last  (cdar ranges))
 358           (while (<= first last)
 359             (setq result (cons first result))
 360             (setq first (1+ first))))
 361         (setq ranges (cdr ranges)))
 362       (nreverse result)))))
 363
 364 (defun gnus-add-to-range (ranges list)
 365   "Return a list of ranges that has all articles from both RANGES and LIST.
 366 Note: LIST has to be sorted over `<'."
 367   (if (not ranges)
 368       (gnus-compress-sequence list t)
 369     (setq list (copy-sequence list))
 370     (unless (listp (cdr ranges))
 371       (setq ranges (list ranges)))
 372     (let ((out ranges)
 373           ilist lowest highest temp)
 374       (while (and ranges list)
 375         (setq ilist list)
 376         (setq lowest (or (and (atom (car ranges)) (car ranges))
 377                          (caar ranges)))
 378         (while (and list (cdr list) (< (cadr list) lowest))
 379           (setq list (cdr list)))
 380         (when (< (car ilist) lowest)
 381           (setq temp list)
 382           (setq list (cdr list))
 383           (setcdr temp nil)
 384           (setq out (nconc (gnus-compress-sequence ilist t) out)))
 385         (setq highest (or (and (atom (car ranges)) (car ranges))
 386                           (cdar ranges)))
 387         (while (and list (<= (car list) highest))
 388           (setq list (cdr list)))
 389         (setq ranges (cdr ranges)))
 390       (when list
 391         (setq out (nconc (gnus-compress-sequence list t) out)))
 392       (setq out (sort out (lambda (r1 r2)
 393                             (< (or (and (atom r1) r1) (car r1))
 394                                (or (and (atom r2) r2) (car r2))))))
 395       (setq ranges out)
 396       (while ranges
 397         (if (atom (car ranges))
 398             (when (cdr ranges)
 399               (if (atom (cadr ranges))
 400                   (when (= (1+ (car ranges)) (cadr ranges))
 401                     (setcar ranges (cons (car ranges)
 402                                          (cadr ranges)))
 403                     (setcdr ranges (cddr ranges)))
 404                 (when (= (1+ (car ranges)) (caadr ranges))
 405                   (setcar (cadr ranges) (car ranges))
 406                   (setcar ranges (cadr ranges))
 407                   (setcdr ranges (cddr ranges)))))
 408           (when (cdr ranges)
 409             (if (atom (cadr ranges))
 410                 (when (= (1+ (cdar ranges)) (cadr ranges))
 411                   (setcdr (car ranges) (cadr ranges))
 412                   (setcdr ranges (cddr ranges)))
 413               (when (= (1+ (cdar ranges)) (caadr ranges))
 414                 (setcdr (car ranges) (cdadr ranges))
 415                 (setcdr ranges (cddr ranges))))))
 416         (setq ranges (cdr ranges)))
 417       out)))
 418
 419 (defun gnus-remove-from-range (range1 range2)
 420   "Return a range that has all articles from RANGE2 removed from RANGE1.
 421 The returned range is always a list.  RANGE2 can also be a unsorted
 422 list of articles.  RANGE1 is modified by side effects, RANGE2 is not
 423 modified."
 424   (if (or (null range1) (null range2))
 425       range1
 426     (let (out r1 r2 r1_min r1_max r2_min r2_max
 427               (range2 (gnus-copy-sequence range2)))
 428       (setq range1 (if (listp (cdr range1)) range1 (list range1))
 429             range2 (sort (if (listp (cdr range2)) range2 (list range2))
 430                          (lambda (e1 e2)
 431                            (< (if (consp e1) (car e1) e1)
 432                               (if (consp e2) (car e2) e2))))
 433             r1 (car range1)
 434             r2 (car range2)
 435             r1_min (if (consp r1) (car r1) r1)
 436             r1_max (if (consp r1) (cdr r1) r1)
 437             r2_min (if (consp r2) (car r2) r2)
 438             r2_max (if (consp r2) (cdr r2) r2))
 439       (while (and range1 range2)
 440         (cond ((< r2_max r1_min)        ; r2 < r1
 441                (pop range2)
 442                (setq r2 (car range2)
 443                      r2_min (if (consp r2) (car r2) r2)
 444                      r2_max (if (consp r2) (cdr r2) r2)))
 445               ((and (<= r2_min r1_min) (<= r1_max r2_max)) ; r2 overlap r1
 446                (pop range1)
 447                (setq r1 (car range1)
 448                      r1_min (if (consp r1) (car r1) r1)
 449                      r1_max (if (consp r1) (cdr r1) r1)))
 450               ((and (<= r2_min r1_min) (<= r2_max r1_max)) ; r2 overlap min r1
 451                (pop range2)
 452                (setq r1_min (1+ r2_max)
 453                      r2 (car range2)
 454                      r2_min (if (consp r2) (car r2) r2)
 455                      r2_max (if (consp r2) (cdr r2) r2)))
 456               ((and (<= r1_min r2_min) (<= r2_max r1_max)) ; r2 contained in r1
 457                (if (eq r1_min (1- r2_min))
 458                    (push r1_min out)
 459                  (push (cons r1_min (1- r2_min)) out))
 460                (pop range2)
 461                (if (< r2_max r1_max)    ; finished with r1?
 462                    (setq r1_min (1+ r2_max))
 463                  (pop range1)
 464                  (setq r1 (car range1)
 465                        r1_min (if (consp r1) (car r1) r1)
 466                        r1_max (if (consp r1) (cdr r1) r1)))
 467                (setq r2 (car range2)
 468                      r2_min (if (consp r2) (car r2) r2)
 469                      r2_max (if (consp r2) (cdr r2) r2)))
 470               ((and (<= r2_min r1_max) (<= r1_max r2_max)) ; r2 overlap max r1
 471                (if (eq r1_min (1- r2_min))
 472                    (push r1_min out)
 473                  (push (cons r1_min (1- r2_min)) out))
 474                (pop range1)
 475                (setq r1 (car range1)
 476                      r1_min (if (consp r1) (car r1) r1)
 477                      r1_max (if (consp r1) (cdr r1) r1)))
 478               ((< r1_max r2_min)        ; r2 > r1
 479                (pop range1)
 480                (if (eq r1_min r1_max)
 481                    (push r1_min out)
 482                  (push (cons r1_min r1_max) out))
 483                (setq r1 (car range1)
 484                      r1_min (if (consp r1) (car r1) r1)
 485                      r1_max (if (consp r1) (cdr r1) r1)))))
 486       (when r1
 487         (if (eq r1_min r1_max)
 488             (push r1_min out)
 489           (push (cons r1_min r1_max) out))
 490         (pop range1))
 491       (while range1
 492         (push (pop range1) out))
 493       (nreverse out))))
 494
 495 (defun gnus-member-of-range (number ranges)
 496   (if (not (listp (cdr ranges)))
 497       (and (>= number (car ranges))
 498            (<= number (cdr ranges)))
 499     (let ((not-stop t))
 500       (while (and ranges
 501                   (if (numberp (car ranges))
 502                       (>= number (car ranges))
 503                     (>= number (caar ranges)))
 504                   not-stop)
 505         (when (if (numberp (car ranges))
 506                   (= number (car ranges))
 507                 (and (>= number (caar ranges))
 508                      (<= number (cdar ranges))))
 509           (setq not-stop nil))
 510         (setq ranges (cdr ranges)))
 511       (not not-stop))))
 512
 513 (defun gnus-list-range-intersection (list ranges)
 514   "Return a list of numbers in LIST that are members of RANGES.
 515 LIST is a sorted list."
 516   (setq ranges (gnus-range-normalize ranges))
 517   (let (number result)
 518     (while (setq number (pop list))
 519       (while (and ranges
 520                   (if (numberp (car ranges))
 521                       (< (car ranges) number)
 522                     (< (cdar ranges) number)))
 523         (setq ranges (cdr ranges)))
 524       (when (and ranges
 525                  (if (numberp (car ranges))
 526                       (= (car ranges) number)
 527                    ;; (caar ranges) <= number <= (cdar ranges)
 528                    (>= number (caar ranges))))
 529         (push number result)))
 530     (nreverse result)))
 531
 532 (defalias 'gnus-inverse-list-range-intersection 'gnus-list-range-difference)
 533
 534 (defun gnus-list-range-difference (list ranges)
 535   "Return a list of numbers in LIST that are not members of RANGES.
 536 LIST is a sorted list."
 537   (setq ranges (gnus-range-normalize ranges))
 538   (let (number result)
 539     (while (setq number (pop list))
 540       (while (and ranges
 541                   (if (numberp (car ranges))
 542                       (< (car ranges) number)
 543                     (< (cdar ranges) number)))
 544         (setq ranges (cdr ranges)))
 545       (when (or (not ranges)
 546                 (if (numberp (car ranges))
 547                     (not (= (car ranges) number))
 548                   ;; not ((caar ranges) <= number <= (cdar ranges))
 549                   (< number (caar ranges))))
 550         (push number result)))
 551     (nreverse result)))
 552
 553 (defun gnus-range-length (range)
 554   "Return the length RANGE would have if uncompressed."
 555   (cond
 556    ((null range)
 557     0)
 558    ((not (listp (cdr range)))
 559     (- (cdr range) (car range) -1))
 560    (t
 561     (let ((sum 0))
 562       (dolist (x range sum)
 563         (setq sum
 564               (+ sum (if (consp x) (- (cdr x) (car x) -1) 1))))))))
 565
 566 (defun gnus-sublist-p (list sublist)
 567   "Test whether all elements in SUBLIST are members of LIST."
 568   (let ((sublistp t))
 569     (while sublist
 570       (unless (memq (pop sublist) list)
 571         (setq sublistp nil
 572               sublist nil)))
 573     sublistp))
 574
 575 (defun gnus-range-add (range1 range2)
 576   "Add RANGE2 to RANGE1 (nondestructively)."
 577   (unless (listp (cdr range1))
 578     (setq range1 (list range1)))
 579   (unless (listp (cdr range2))
 580     (setq range2 (list range2)))
 581   (let ((item1 (pop range1))
 582         (item2 (pop range2))
 583         range item selector)
 584     (while (or item1 item2)
 585       (setq selector
 586             (cond
 587              ((null item1) nil)
 588              ((null item2) t)
 589              ((and (numberp item1) (numberp item2)) (< item1 item2))
 590              ((numberp item1) (< item1 (car item2)))
 591              ((numberp item2) (< (car item1) item2))
 592              (t (< (car item1) (car item2)))))
 593       (setq item
 594             (or
 595              (let ((tmp1 item) (tmp2 (if selector item1 item2)))
 596                (cond
 597                 ((null tmp1) tmp2)
 598                 ((null tmp2) tmp1)
 599                 ((and (numberp tmp1) (numberp tmp2))
 600                  (cond
 601                   ((eq tmp1 tmp2) tmp1)
 602                   ((eq (1+ tmp1) tmp2) (cons tmp1 tmp2))
 603                   ((eq (1+ tmp2) tmp1) (cons tmp2 tmp1))
 604                   (t nil)))
 605                 ((numberp tmp1)
 606                  (cond
 607                   ((and (>= tmp1 (car tmp2)) (<= tmp1 (cdr tmp2))) tmp2)
 608                   ((eq (1+ tmp1) (car tmp2)) (cons tmp1 (cdr tmp2)))
 609                   ((eq (1- tmp1) (cdr tmp2)) (cons (car tmp2) tmp1))
 610                   (t nil)))
 611                 ((numberp tmp2)
 612                  (cond
 613                   ((and (>= tmp2 (car tmp1)) (<= tmp2 (cdr tmp1))) tmp1)
 614                   ((eq (1+ tmp2) (car tmp1)) (cons tmp2 (cdr tmp1)))
 615                   ((eq (1- tmp2) (cdr tmp1)) (cons (car tmp1) tmp2))
 616                   (t nil)))
 617                 ((< (1+ (cdr tmp1)) (car tmp2)) nil)
 618                 ((< (1+ (cdr tmp2)) (car tmp1)) nil)
 619                 (t (cons (min (car tmp1) (car tmp2))
 620                          (max (cdr tmp1) (cdr tmp2))))))
 621              (progn
 622                (if item (push item range))
 623                (if selector item1 item2))))
 624       (if selector
 625           (setq item1 (pop range1))
 626         (setq item2 (pop range2))))
 627     (if item (push item range))
 628     (reverse range)))
 629
 630 ;;;###autoload
 631 (defun gnus-add-to-sorted-list (list num)
 632   "Add NUM into sorted LIST by side effect."
 633   (let* ((top (cons nil list))
 634          (prev top))
 635     (while (and list (< (car list) num))
 636       (setq prev list
 637             list (cdr list)))
 638     (unless (eq (car list) num)
 639       (setcdr prev (cons num list)))
 640     (cdr top)))
 641
 642 (defun gnus-range-map (func range)
 643   "Apply FUNC to each value contained by RANGE."
 644   (setq range (gnus-range-normalize range))
 645   (while range
 646     (let ((span (pop range)))
 647       (if (numberp span)
 648           (funcall func span)
 649         (let ((first (car span))
 650               (last (cdr span)))
 651           (while (<= first last)
 652             (funcall func first)
 653             (setq first (1+ first))))))))
 654
 655 (provide 'gnus-range)
 656
 657 ;; arch-tag: 4780bdd8-5a15-4aff-be28-18727895b6ad
 658 ;;; gnus-range.el ends here