src/category.c

   1 /* GNU Emacs routines to deal with category tables.
   2    Copyright (C) 1995, 1997 Electrotechnical Laboratory, JAPAN.
   3    Licensed to the Free Software Foundation.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22
  23 /* Here we handle three objects: category, category set, and category
  24    table.  Read comments in the file category.h to understand them.  */
  25
  26 #include <config.h>
  27 #include <ctype.h>
  28 #include "lisp.h"
  29 #include "buffer.h"
  30 #include "charset.h"
  31 #include "category.h"
  32 #include "keymap.h"
  33
  34 /* The version number of the latest category table.  Each category
  35    table has a unique version number.  It is assigned a new number
  36    also when it is modified.  When a regular expression is compiled
  37    into the struct re_pattern_buffer, the version number of the
  38    category table (of the current buffer) at that moment is also
  39    embedded in the structure.
  40
  41    For the moment, we are not using this feature.  */
  42 static int category_table_version;
  43
  44 Lisp_Object Qcategory_table, Qcategoryp, Qcategorysetp, Qcategory_table_p;
  45
  46 /* Variables to determine word boundary.  */
  47 Lisp_Object Vword_combining_categories, Vword_separating_categories;
  48
  49 /* Temporary internal variable used in macro CHAR_HAS_CATEGORY.  */
  50 Lisp_Object _temp_category_set;
  51
  52 \f
  53 /* Category set staff.  */
  54
  55 DEFUN ("make-category-set", Fmake_category_set, Smake_category_set, 1, 1, 0,
  56        doc: /* Return a newly created category-set which contains CATEGORIES.
  57 CATEGORIES is a string of category mnemonics.
  58 The value is a bool-vector which has t at the indices corresponding to
  59 those categories.  */)
  60      (categories)
  61      Lisp_Object categories;
  62 {
  63   Lisp_Object val;
  64   int len;
  65
  66   CHECK_STRING (categories, 0);
  67   val = MAKE_CATEGORY_SET;
  68
  69   if (STRING_MULTIBYTE (categories))
  70     error ("Multibyte string in make-category-set");
  71
  72   len = XSTRING (categories)->size;
  73   while (--len >= 0)
  74     {
  75       Lisp_Object category;
  76
  77       XSETFASTINT (category, XSTRING (categories)->data[len]);
  78       CHECK_CATEGORY (category, 0);
  79       SET_CATEGORY_SET (val, category, Qt);
  80     }
  81   return val;
  82 }
  83
  84 \f
  85 /* Category staff.  */
  86
  87 Lisp_Object check_category_table ();
  88
  89 DEFUN ("define-category", Fdefine_category, Sdefine_category, 2, 3, 0,
  90        doc: /* Define CHAR as a category which is described by DOCSTRING.
  91 CHAR should be an ASCII printing character in the range ` ' to `~'.
  92 DOCSTRING is a documentation string of the category.
  93 The category is defined only in category table TABLE, which defaults to
  94  the current buffer's category table.  */)
  95      (category, docstring, table)
  96      Lisp_Object category, docstring, table;
  97 {
  98   CHECK_CATEGORY (category, 0);
  99   CHECK_STRING (docstring, 1);
 100   table = check_category_table (table);
 101
 102   if (!NILP (CATEGORY_DOCSTRING (table, XFASTINT (category))))
 103     error ("Category `%c' is already defined", XFASTINT (category));
 104   CATEGORY_DOCSTRING (table, XFASTINT (category)) = docstring;
 105
 106   return Qnil;
 107 }
 108
 109 DEFUN ("category-docstring", Fcategory_docstring, Scategory_docstring, 1, 2, 0,
 110        doc: /* Return the documentation string of CATEGORY, as defined in CATEGORY-TABLE.  */)
 111      (category, table)
 112      Lisp_Object category, table;
 113 {
 114   CHECK_CATEGORY (category, 0);
 115   table = check_category_table (table);
 116
 117   return CATEGORY_DOCSTRING (table, XFASTINT (category));
 118 }
 119
 120 DEFUN ("get-unused-category", Fget_unused_category, Sget_unused_category,
 121        0, 1, 0,
 122        doc: /* Return a category which is not yet defined in CATEGORY-TABLE.  If no
 123 category remains available, return nil.  The optional argument CATEGORY-TABLE
 124 specifies which category table to modify; it defaults to the current
 125 buffer's category table.  */)
 126      (table)
 127      Lisp_Object table;
 128 {
 129   int i;
 130
 131   table = check_category_table (table);
 132
 133   for (i = ' '; i <= '~'; i++)
 134     if (NILP (CATEGORY_DOCSTRING (table, i)))
 135       return make_number (i);
 136
 137   return Qnil;
 138 }
 139
 140 \f
 141 /* Category-table staff.  */
 142
 143 DEFUN ("category-table-p", Fcategory_table_p, Scategory_table_p, 1, 1, 0,
 144        doc: /* Return t if ARG is a category table.  */)
 145      (arg)
 146      Lisp_Object arg;
 147 {
 148   if (CHAR_TABLE_P (arg)
 149       && EQ (XCHAR_TABLE (arg)->purpose, Qcategory_table))
 150     return Qt;
 151   return Qnil;
 152 }
 153
 154 /* If TABLE is nil, return the current category table.  If TABLE is
 155    not nil, check the validity of TABLE as a category table.  If
 156    valid, return TABLE itself, but if not valid, signal an error of
 157    wrong-type-argument.  */
 158
 159 Lisp_Object
 160 check_category_table (table)
 161      Lisp_Object table;
 162 {
 163   register Lisp_Object tem;
 164   if (NILP (table))
 165     return current_buffer->category_table;
 166   while (tem = Fcategory_table_p (table), NILP (tem))
 167     table = wrong_type_argument (Qcategory_table_p, table);
 168   return table;
 169 }
 170
 171 DEFUN ("category-table", Fcategory_table, Scategory_table, 0, 0, 0,
 172        doc: /* Return the current category table.
 173 This is the one specified by the current buffer.  */)
 174      ()
 175 {
 176   return current_buffer->category_table;
 177 }
 178
 179 DEFUN ("standard-category-table", Fstandard_category_table,
 180    Sstandard_category_table, 0, 0, 0,
 181        doc: /* Return the standard category table.
 182 This is the one used for new buffers.  */)
 183      ()
 184 {
 185   return Vstandard_category_table;
 186 }
 187
 188 /* Return a copy of category table TABLE.  We can't simply use the
 189    function copy-sequence because no contents should be shared between
 190    the original and the copy.  This function is called recursively by
 191    binding TABLE to a sub char table.  */
 192
 193 Lisp_Object
 194 copy_category_table (table)
 195      Lisp_Object table;
 196 {
 197   Lisp_Object tmp;
 198   int i, to;
 199
 200   if (!NILP (XCHAR_TABLE (table)->top))
 201     {
 202       /* TABLE is a top level char table.
 203          At first, make a copy of tree structure of the table.  */
 204       table = Fcopy_sequence (table);
 205
 206       /* Then, copy elements for single byte characters one by one.  */
 207       for (i = 0; i < CHAR_TABLE_SINGLE_BYTE_SLOTS; i++)
 208         if (!NILP (tmp = XCHAR_TABLE (table)->contents[i]))
 209           XCHAR_TABLE (table)->contents[i] = Fcopy_sequence (tmp);
 210       to = CHAR_TABLE_ORDINARY_SLOTS;
 211
 212       /* Also copy the first (and sole) extra slot.  It is a vector
 213          containing docstring of each category.  */
 214       Fset_char_table_extra_slot
 215         (table, make_number (0),
 216          Fcopy_sequence (Fchar_table_extra_slot (table, make_number (0))));
 217     }
 218   else
 219     {
 220       i  = 32;
 221       to = SUB_CHAR_TABLE_ORDINARY_SLOTS;
 222     }
 223
 224   /* If the table has non-nil default value, copy it.  */
 225   if (!NILP (tmp = XCHAR_TABLE (table)->defalt))
 226     XCHAR_TABLE (table)->defalt = Fcopy_sequence (tmp);
 227
 228   /* At last, copy the remaining elements while paying attention to a
 229      sub char table.  */
 230   for (; i < to; i++)
 231     if (!NILP (tmp = XCHAR_TABLE (table)->contents[i]))
 232       XCHAR_TABLE (table)->contents[i]
 233         = (SUB_CHAR_TABLE_P (tmp)
 234            ? copy_category_table (tmp) : Fcopy_sequence (tmp));
 235
 236   return table;
 237 }
 238
 239 DEFUN ("copy-category-table", Fcopy_category_table, Scopy_category_table,
 240        0, 1, 0,
 241        doc: /* Construct a new category table and return it.
 242 It is a copy of the TABLE, which defaults to the standard category table.  */)
 243      (table)
 244      Lisp_Object table;
 245 {
 246   if (!NILP (table))
 247     check_category_table (table);
 248   else
 249     table = Vstandard_category_table;
 250
 251   return copy_category_table (table);
 252 }
 253
 254 DEFUN ("make-category-table", Fmake_category_table, Smake_category_table,
 255        0, 0, 0,
 256        doc: /* Construct a new and empty category table and return it.  */)
 257      ()
 258 {
 259   Lisp_Object val;
 260
 261   val = Fmake_char_table (Qcategory_table, Qnil);
 262   XCHAR_TABLE (val)->defalt = MAKE_CATEGORY_SET;
 263   Fset_char_table_extra_slot (val, make_number (0),
 264                               Fmake_vector (make_number (95), Qnil));
 265   return val;
 266 }
 267
 268 DEFUN ("set-category-table", Fset_category_table, Sset_category_table, 1, 1, 0,
 269        doc: /* Specify TABLE as the category table for the current buffer.  */)
 270      (table)
 271      Lisp_Object table;
 272 {
 273   int idx;
 274   table = check_category_table (table);
 275   current_buffer->category_table = table;
 276   /* Indicate that this buffer now has a specified category table.  */
 277   idx = PER_BUFFER_VAR_IDX (category_table);
 278   SET_PER_BUFFER_VALUE_P (current_buffer, idx, 1);
 279   return table;
 280 }
 281
 282 \f
 283 DEFUN ("char-category-set", Fchar_category_set, Schar_category_set, 1, 1, 0,
 284        doc: /* Return the category set of CHAR.  */)
 285      (ch)
 286      Lisp_Object ch;
 287 {
 288   CHECK_NUMBER (ch, 0);
 289   return CATEGORY_SET (XFASTINT (ch));
 290 }
 291
 292 DEFUN ("category-set-mnemonics", Fcategory_set_mnemonics,
 293        Scategory_set_mnemonics, 1, 1, 0,
 294        doc: /* Return a string containing mnemonics of the categories in CATEGORY-SET.
 295 CATEGORY-SET is a bool-vector, and the categories \"in\" it are those
 296 that are indexes where t occurs the bool-vector.
 297 The return value is a string containing those same categories.  */)
 298      (category_set)
 299      Lisp_Object category_set;
 300 {
 301   int i, j;
 302   char str[96];
 303
 304   CHECK_CATEGORY_SET (category_set, 0);
 305
 306   j = 0;
 307   for (i = 32; i < 127; i++)
 308     if (CATEGORY_MEMBER (i, category_set))
 309       str[j++] = i;
 310   str[j] = '\0';
 311
 312   return build_string (str);
 313 }
 314
 315 /* Modify all category sets stored under sub char-table TABLE so that
 316    they contain (SET_VALUE is t) or don't contain (SET_VALUE is nil)
 317    CATEGORY.  */
 318
 319 void
 320 modify_lower_category_set (table, category, set_value)
 321      Lisp_Object table, category, set_value;
 322 {
 323   Lisp_Object val;
 324   int i;
 325
 326   val = XCHAR_TABLE (table)->defalt;
 327   if (!CATEGORY_SET_P (val))
 328     val = MAKE_CATEGORY_SET;
 329   SET_CATEGORY_SET (val, category, set_value);
 330   XCHAR_TABLE (table)->defalt = val;
 331
 332   for (i = 32; i < SUB_CHAR_TABLE_ORDINARY_SLOTS; i++)
 333     {
 334       val = XCHAR_TABLE (table)->contents[i];
 335
 336       if (CATEGORY_SET_P (val))
 337         SET_CATEGORY_SET (val, category, set_value);
 338       else if (SUB_CHAR_TABLE_P (val))
 339         modify_lower_category_set (val, category, set_value);
 340     }
 341 }
 342
 343 void
 344 set_category_set (category_set, category, val)
 345      Lisp_Object category_set, category, val;
 346 {
 347   do {
 348     int idx = XINT (category) / 8;
 349     unsigned char bits = 1 << (XINT (category) % 8);
 350
 351     if (NILP (val))
 352       XCATEGORY_SET (category_set)->data[idx] &= ~bits;
 353     else
 354       XCATEGORY_SET (category_set)->data[idx] |= bits;
 355   } while (0);
 356 }
 357
 358 DEFUN ("modify-category-entry", Fmodify_category_entry,
 359        Smodify_category_entry, 2, 4, 0,
 360        doc: /* Modify the category set of CHARACTER by adding CATEGORY to it.
 361 The category is changed only for table TABLE, which defaults to
 362  the current buffer's category table.
 363 If optional fourth argument RESET is non-nil,
 364 then delete CATEGORY from the category set instead of adding it.  */)
 365      (character, category, table, reset)
 366      Lisp_Object character, category, table, reset;
 367 {
 368   int c, charset, c1, c2;
 369   Lisp_Object set_value;        /* Actual value to be set in category sets.  */
 370   Lisp_Object val, category_set;
 371
 372   CHECK_NUMBER (character, 0);
 373   c = XINT (character);
 374   CHECK_CATEGORY (category, 1);
 375   table = check_category_table (table);
 376
 377   if (NILP (CATEGORY_DOCSTRING (table, XFASTINT (category))))
 378     error ("Undefined category: %c", XFASTINT (category));
 379
 380   set_value = NILP (reset) ? Qt : Qnil;
 381
 382   if (c < CHAR_TABLE_SINGLE_BYTE_SLOTS)
 383     {
 384       val = XCHAR_TABLE (table)->contents[c];
 385       if (!CATEGORY_SET_P (val))
 386         XCHAR_TABLE (table)->contents[c] = (val = MAKE_CATEGORY_SET);
 387       SET_CATEGORY_SET (val, category, set_value);
 388       return Qnil;
 389     }
 390
 391   SPLIT_CHAR (c, charset, c1, c2);
 392
 393   /* The top level table.  */
 394   val = XCHAR_TABLE (table)->contents[charset + 128];
 395   if (CATEGORY_SET_P (val))
 396     category_set = val;
 397   else if (!SUB_CHAR_TABLE_P (val))
 398     {
 399       category_set = val = MAKE_CATEGORY_SET;
 400       XCHAR_TABLE (table)->contents[charset + 128] = category_set;
 401     }
 402
 403   if (c1 <= 0)
 404     {
 405       /* Only a charset is specified.  */
 406       if (SUB_CHAR_TABLE_P (val))
 407         /* All characters in CHARSET should be the same as for having
 408            CATEGORY or not.  */
 409         modify_lower_category_set (val, category, set_value);
 410       else
 411         SET_CATEGORY_SET (category_set, category, set_value);
 412       return Qnil;
 413     }
 414
 415   /* The second level table.  */
 416   if (!SUB_CHAR_TABLE_P (val))
 417     {
 418       val = make_sub_char_table (Qnil);
 419       XCHAR_TABLE (table)->contents[charset + 128] = val;
 420       /* We must set default category set of CHARSET in `defalt' slot.  */
 421       XCHAR_TABLE (val)->defalt = category_set;
 422     }
 423   table = val;
 424
 425   val = XCHAR_TABLE (table)->contents[c1];
 426   if (CATEGORY_SET_P (val))
 427     category_set = val;
 428   else if (!SUB_CHAR_TABLE_P (val))
 429     {
 430       category_set = val = Fcopy_sequence (XCHAR_TABLE (table)->defalt);
 431       XCHAR_TABLE (table)->contents[c1] = category_set;
 432     }
 433
 434   if (c2 <= 0)
 435     {
 436       if (SUB_CHAR_TABLE_P (val))
 437         /* All characters in C1 group of CHARSET should be the same as
 438            for CATEGORY.  */
 439         modify_lower_category_set (val, category, set_value);
 440       else
 441         SET_CATEGORY_SET (category_set, category, set_value);
 442       return Qnil;
 443     }
 444
 445   /* The third (bottom) level table.  */
 446   if (!SUB_CHAR_TABLE_P (val))
 447     {
 448       val = make_sub_char_table (Qnil);
 449       XCHAR_TABLE (table)->contents[c1] = val;
 450       /* We must set default category set of CHARSET and C1 in
 451          `defalt' slot.  */
 452       XCHAR_TABLE (val)->defalt = category_set;
 453     }
 454   table = val;
 455
 456   val = XCHAR_TABLE (table)->contents[c2];
 457   if (CATEGORY_SET_P (val))
 458     category_set = val;
 459   else if (!SUB_CHAR_TABLE_P (val))
 460     {
 461       category_set = Fcopy_sequence (XCHAR_TABLE (table)->defalt);
 462       XCHAR_TABLE (table)->contents[c2] = category_set;
 463     }
 464   else
 465     /* This should never happen.  */
 466     error ("Invalid category table");
 467
 468   SET_CATEGORY_SET (category_set, category, set_value);
 469
 470   return Qnil;
 471 }
 472 \f
 473 /* Dump category table to buffer in human-readable format */
 474
 475 static void
 476 describe_category (value)
 477     Lisp_Object value;
 478 {
 479   Lisp_Object mnemonics;
 480
 481   Findent_to (make_number (16), make_number (1));
 482
 483   if (NILP (value))
 484     {
 485       insert_string ("default\n");
 486       return;
 487     }
 488
 489   if (CHAR_TABLE_P (value))
 490     {
 491       insert_string ("deeper char-table ...\n");
 492       return;
 493     }
 494
 495   if (!CATEGORY_SET_P (value))
 496     {
 497       insert_string ("invalid\n");
 498       return;
 499     }
 500
 501   mnemonics = Fcategory_set_mnemonics (value);
 502   insert_from_string (mnemonics, 0, 0, XSTRING (mnemonics)->size,
 503                       STRING_BYTES (XSTRING (mnemonics)), 0);
 504   insert_string ("\n");
 505   return;
 506 }
 507
 508 static Lisp_Object
 509 describe_category_1 (vector)
 510      Lisp_Object vector;
 511 {
 512   struct buffer *old = current_buffer;
 513   set_buffer_internal (XBUFFER (Vstandard_output));
 514   describe_vector (vector, Qnil, describe_category, 0, Qnil, Qnil,
 515                    (int *)0, 0);
 516   {
 517     int i;
 518     Lisp_Object docs = XCHAR_TABLE (vector)->extras[0];
 519     Lisp_Object elt;
 520
 521     if (!VECTORP (docs) || XVECTOR (docs)->size != 95)
 522       {
 523         insert_string ("Invalid first extra slot in this char table\n");
 524         return Qnil;
 525       }
 526
 527     insert_string ("Meanings of mnemonice characters are:\n");
 528     for (i = 0; i < 95; i++)
 529       {
 530         elt = XVECTOR (docs)->contents[i];
 531         if (NILP (elt))
 532           continue;
 533
 534         insert_char (i + 32);
 535         insert (": ", 2);
 536         insert_from_string (elt, 0, 0, XSTRING (elt)->size,
 537                             STRING_BYTES (XSTRING (elt)), 0);
 538         insert ("\n", 1);
 539       }
 540   }
 541
 542   while (! NILP (XCHAR_TABLE (vector)->parent))
 543     {
 544       vector = XCHAR_TABLE (vector)->parent;
 545       insert_string ("\nThe parent category table is:");
 546       describe_vector (vector, Qnil, describe_category, 0, Qnil, Qnil,
 547                        (int *) 0, 0);
 548     }
 549
 550   call0 (intern ("help-mode"));
 551   set_buffer_internal (old);
 552   return Qnil;
 553 }
 554
 555 DEFUN ("describe-categories", Fdescribe_categories, Sdescribe_categories, 0, 0, "",
 556        doc: /* Describe the category specifications in the current category table.
 557 The descriptions are inserted in a buffer, which is then displayed.  */)
 558      ()
 559 {
 560   internal_with_output_to_temp_buffer
 561      ("*Help*", describe_category_1, current_buffer->category_table);
 562
 563   return Qnil;
 564 }
 565 \f
 566 /* Return 1 if there is a word boundary between two word-constituent
 567    characters C1 and C2 if they appear in this order, else return 0.
 568    Use the macro WORD_BOUNDARY_P instead of calling this function
 569    directly.  */
 570
 571 int
 572 word_boundary_p (c1, c2)
 573      int c1, c2;
 574 {
 575   Lisp_Object category_set1, category_set2;
 576   Lisp_Object tail;
 577   int default_result;
 578
 579   if (CHAR_CHARSET (c1) == CHAR_CHARSET (c2))
 580     {
 581       tail = Vword_separating_categories;
 582       default_result = 0;
 583     }
 584   else
 585     {
 586       tail = Vword_combining_categories;
 587       default_result = 1;
 588     }
 589
 590   category_set1 = CATEGORY_SET (c1);
 591   if (NILP (category_set1))
 592     return default_result;
 593   category_set2 = CATEGORY_SET (c2);
 594   if (NILP (category_set2))
 595     return default_result;
 596
 597   for (; CONSP (tail); tail = XCDR (tail))
 598     {
 599       Lisp_Object elt = XCAR (tail);
 600
 601       if (CONSP (elt)
 602           && CATEGORYP (XCAR (elt))
 603           && CATEGORYP (XCDR (elt))
 604           && CATEGORY_MEMBER (XFASTINT (XCAR (elt)), category_set1)
 605           && CATEGORY_MEMBER (XFASTINT (XCDR (elt)), category_set2))
 606         return !default_result;
 607     }
 608   return default_result;
 609 }
 610
 611 \f
 612 void
 613 init_category_once ()
 614 {
 615   /* This has to be done here, before we call Fmake_char_table.  */
 616   Qcategory_table = intern ("category-table");
 617   staticpro (&Qcategory_table);
 618
 619   /* Intern this now in case it isn't already done.
 620      Setting this variable twice is harmless.
 621      But don't staticpro it here--that is done in alloc.c.  */
 622   Qchar_table_extra_slots = intern ("char-table-extra-slots");
 623
 624   /* Now we are ready to set up this property, so we can
 625      create category tables.  */
 626   Fput (Qcategory_table, Qchar_table_extra_slots, make_number (2));
 627
 628   Vstandard_category_table = Fmake_char_table (Qcategory_table, Qnil);
 629   /* Set a category set which contains nothing to the default.  */
 630   XCHAR_TABLE (Vstandard_category_table)->defalt = MAKE_CATEGORY_SET;
 631   Fset_char_table_extra_slot (Vstandard_category_table, make_number (0),
 632                               Fmake_vector (make_number (95), Qnil));
 633 }
 634
 635 void
 636 syms_of_category ()
 637 {
 638   Qcategoryp = intern ("categoryp");
 639   staticpro (&Qcategoryp);
 640   Qcategorysetp = intern ("categorysetp");
 641   staticpro (&Qcategorysetp);
 642   Qcategory_table_p = intern ("category-table-p");
 643   staticpro (&Qcategory_table_p);
 644
 645   DEFVAR_LISP ("word-combining-categories", &Vword_combining_categories,
 646                doc: /* List of pair (cons) of categories to determine word boundary.
 647
 648 Emacs treats a sequence of word constituent characters as a single
 649 word (i.e. finds no word boundary between them) iff they belongs to
 650 the same charset.  But, exceptions are allowed in the following cases.
 651
 652 \(1) The case that characters are in different charsets is controlled
 653 by the variable `word-combining-categories'.
 654
 655 Emacs finds no word boundary between characters of different charsets
 656 if they have categories matching some element of this list.
 657
 658 More precisely, if an element of this list is a cons of category CAT1
 659 and CAT2, and a multibyte character C1 which has CAT1 is followed by
 660 C2 which has CAT2, there's no word boundary between C1 and C2.
 661
 662 For instance, to tell that ASCII characters and Latin-1 characters can
 663 form a single word, the element `(?l . ?l)' should be in this list
 664 because both characters have the category `l' (Latin characters).
 665
 666 \(2) The case that character are in the same charset is controlled by
 667 the variable `word-separating-categories'.
 668
 669 Emacs find a word boundary between characters of the same charset
 670 if they have categories matching some element of this list.
 671
 672 More precisely, if an element of this list is a cons of category CAT1
 673 and CAT2, and a multibyte character C1 which has CAT1 is followed by
 674 C2 which has CAT2, there's a word boundary between C1 and C2.
 675
 676 For instance, to tell that there's a word boundary between Japanese
 677 Hiragana and Japanese Kanji (both are in the same charset), the
 678 element `(?H . ?C) should be in this list.  */);
 679
 680   Vword_combining_categories = Qnil;
 681
 682   DEFVAR_LISP ("word-separating-categories", &Vword_separating_categories,
 683                doc: /* List of pair (cons) of categories to determine word boundary.
 684 See the documentation of the variable `word-combining-categories'.  */);
 685
 686   Vword_separating_categories = Qnil;
 687
 688   defsubr (&Smake_category_set);
 689   defsubr (&Sdefine_category);
 690   defsubr (&Scategory_docstring);
 691   defsubr (&Sget_unused_category);
 692   defsubr (&Scategory_table_p);
 693   defsubr (&Scategory_table);
 694   defsubr (&Sstandard_category_table);
 695   defsubr (&Scopy_category_table);
 696   defsubr (&Smake_category_table);
 697   defsubr (&Sset_category_table);
 698   defsubr (&Schar_category_set);
 699   defsubr (&Scategory_set_mnemonics);
 700   defsubr (&Smodify_category_entry);
 701   defsubr (&Sdescribe_categories);
 702
 703   category_table_version = 0;
 704 }