1;;; mule-util.el --- utility functions for mulitilingual environment (mule) 2 3;; Copyright (C) 1997, 1998, 2000, 2001, 2002, 2003, 2004, 4;; 2005, 2006, 2007 Free Software Foundation, Inc. 5;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 6;; 2005, 2006, 2007 7;; National Institute of Advanced Industrial Science and Technology (AIST) 8;; Registration Number H14PRO021 9 10;; Keywords: mule, multilingual 11 12;; This file is part of GNU Emacs. 13 14;; GNU Emacs is free software; you can redistribute it and/or modify 15;; it under the terms of the GNU General Public License as published by 16;; the Free Software Foundation; either version 2, or (at your option) 17;; any later version. 18 19;; GNU Emacs is distributed in the hope that it will be useful, 20;; but WITHOUT ANY WARRANTY; without even the implied warranty of 21;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22;; GNU General Public License for more details. 23 24;; You should have received a copy of the GNU General Public License 25;; along with GNU Emacs; see the file COPYING. If not, write to the 26;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 27;; Boston, MA 02110-1301, USA. 28 29;;; Commentary: 30 31;;; Code: 32 33;;; String manipulations while paying attention to multibyte 34;;; characters. 35 36;;;###autoload 37(defun string-to-sequence (string type) 38 "Convert STRING to a sequence of TYPE which contains characters in STRING. 39TYPE should be `list' or `vector'." 40;;; (let ((len (length string)) 41;;; (i 0) 42;;; val) 43 (cond ((eq type 'list) 44 ;; Applicable post-Emacs 20.2 and asymptotically ~10 times 45 ;; faster than the code below: 46 (append string nil)) 47;;; (setq val (make-list len 0)) 48;;; (let ((l val)) 49;;; (while (< i len) 50;;; (setcar l (aref string i)) 51;;; (setq l (cdr l) i (1+ i)))))) 52 ((eq type 'vector) 53 ;; As above. 54 (vconcat string)) 55;;; (setq val (make-vector len 0)) 56;;; (while (< i len) 57;;; (aset val i (aref string i)) 58;;; (setq i (1+ i)))) 59 (t 60 (error "Invalid type: %s" type))) 61;;; val) 62) 63 64;;;###autoload 65(make-obsolete 'string-to-sequence 66 "use `string-to-list' or `string-to-vector'." 67 "22.1") 68 69;;;###autoload 70(defsubst string-to-list (string) 71 "Return a list of characters in STRING." 72 (append string nil)) 73 74;;;###autoload 75(defsubst string-to-vector (string) 76 "Return a vector of characters in STRING." 77 (vconcat string)) 78 79;;;###autoload 80(defun store-substring (string idx obj) 81 "Embed OBJ (string or character) at index IDX of STRING." 82 (if (integerp obj) 83 (aset string idx obj) 84 (let ((len1 (length obj)) 85 (len2 (length string)) 86 (i 0)) 87 (while (< i len1) 88 (aset string (+ idx i) (aref obj i)) 89 (setq i (1+ i))))) 90 string) 91 92;;;###autoload 93(defun truncate-string-to-width (str end-column 94 &optional start-column padding ellipsis) 95 "Truncate string STR to end at column END-COLUMN. 96The optional 3rd arg START-COLUMN, if non-nil, specifies the starting 97column; that means to return the characters occupying columns 98START-COLUMN ... END-COLUMN of STR. Both END-COLUMN and START-COLUMN 99are specified in terms of character display width in the current 100buffer; see also `char-width'. 101 102The optional 4th arg PADDING, if non-nil, specifies a padding 103character (which should have a display width of 1) to add at the end 104of the result if STR doesn't reach column END-COLUMN, or if END-COLUMN 105comes in the middle of a character in STR. PADDING is also added at 106the beginning of the result if column START-COLUMN appears in the 107middle of a character in STR. 108 109If PADDING is nil, no padding is added in these cases, so 110the resulting string may be narrower than END-COLUMN. 111 112If ELLIPSIS is non-nil, it should be a string which will replace the 113end of STR (including any padding) if it extends beyond END-COLUMN, 114unless the display width of STR is equal to or less than the display 115width of ELLIPSIS. If it is non-nil and not a string, then ELLIPSIS 116defaults to \"...\"." 117 (or start-column 118 (setq start-column 0)) 119 (when (and ellipsis (not (stringp ellipsis))) 120 (setq ellipsis "...")) 121 (let ((str-len (length str)) 122 (str-width (string-width str)) 123 (ellipsis-len (if ellipsis (length ellipsis) 0)) 124 (ellipsis-width (if ellipsis (string-width ellipsis) 0)) 125 (idx 0) 126 (column 0) 127 (head-padding "") (tail-padding "") 128 ch last-column last-idx from-idx) 129 (condition-case nil 130 (while (< column start-column) 131 (setq ch (aref str idx) 132 column (+ column (char-width ch)) 133 idx (1+ idx))) 134 (args-out-of-range (setq idx str-len))) 135 (if (< column start-column) 136 (if padding (make-string end-column padding) "") 137 (when (and padding (> column start-column)) 138 (setq head-padding (make-string (- column start-column) padding))) 139 (setq from-idx idx) 140 (when (>= end-column column) 141 (if (and (< end-column str-width) 142 (> str-width ellipsis-width)) 143 (setq end-column (- end-column ellipsis-width)) 144 (setq ellipsis "")) 145 (condition-case nil 146 (while (< column end-column) 147 (setq last-column column 148 last-idx idx 149 ch (aref str idx) 150 column (+ column (char-width ch)) 151 idx (1+ idx))) 152 (args-out-of-range (setq idx str-len))) 153 (when (> column end-column) 154 (setq column last-column 155 idx last-idx)) 156 (when (and padding (< column end-column)) 157 (setq tail-padding (make-string (- end-column column) padding)))) 158 (concat head-padding (substring str from-idx idx) 159 tail-padding ellipsis)))) 160 161;;; Test suite for truncate-string-to-width 162;; (dolist (test '((("" 0) . "") 163;; (("x" 1) . "x") 164;; (("xy" 1) . "x") 165;; (("xy" 2 1) . "y") 166;; (("xy" 0) . "") 167;; (("xy" 3) . "xy") 168;; (("$AVP(B" 0) . "") 169;; (("$AVP(B" 1) . "") 170;; (("$AVP(B" 2) . "$AVP(B") 171;; (("$AVP(B" 1 nil ? ) . " ") 172;; (("$AVPND(B" 3 1 ? ) . " ") 173;; (("x$AVP(Bx" 2) . "x") 174;; (("x$AVP(Bx" 3) . "x$AVP(B") 175;; (("x$AVP(Bx" 3) . "x$AVP(B") 176;; (("x$AVP(Bx" 4 1) . "$AVP(Bx") 177;; (("kor$(CGQ(Be$(C1[(Ban" 8 1 ? ) . "or$(CGQ(Be$(C1[(B") 178;; (("kor$(CGQ(Be$(C1[(Ban" 7 2 ? ) . "r$(CGQ(Be ") 179;; (("" 0 nil nil "...") . "") 180;; (("x" 3 nil nil "...") . "x") 181;; (("$AVP(B" 3 nil nil "...") . "$AVP(B") 182;; (("foo" 3 nil nil "...") . "foo") 183;; (("foo" 2 nil nil "...") . "fo") ;; XEmacs failure? 184;; (("foobar" 6 0 nil "...") . "foobar") 185;; (("foobarbaz" 6 nil nil "...") . "foo...") 186;; (("foobarbaz" 7 2 nil "...") . "ob...") 187;; (("foobarbaz" 9 3 nil "...") . "barbaz") 188;; (("$B$3(Bh$B$s(Be$B$K(Bl$B$A(Bl$B$O(Bo" 15 1 ? t) . " h$B$s(Be$B$K(Bl$B$A(Bl$B$O(Bo") 189;; (("$B$3(Bh$B$s(Be$B$K(Bl$B$A(Bl$B$O(Bo" 14 1 ? t) . " h$B$s(Be$B$K(Bl$B$A(B...") 190;; (("x" 3 nil nil "$(0GnM$(B") . "x") 191;; (("$AVP(B" 2 nil nil "$(0GnM$(B") . "$AVP(B") 192;; (("$AVP(B" 1 nil ?x "$(0GnM$(B") . "x") ;; XEmacs error 193;; (("$AVPND(B" 3 nil ? "$(0GnM$(B") . "$AVP(B ") ;; XEmacs error 194;; (("foobarbaz" 4 nil nil "$(0GnM$(B") . "$(0GnM$(B") 195;; (("foobarbaz" 5 nil nil "$(0GnM$(B") . "f$(0GnM$(B") 196;; (("foobarbaz" 6 nil nil "$(0GnM$(B") . "fo$(0GnM$(B") 197;; (("foobarbaz" 8 3 nil "$(0GnM$(B") . "b$(0GnM$(B") 198;; (("$B$3(Bh$B$s(Be$B$K(Bl$B$A(Bl$B$O(Bo" 14 4 ?x "$BF|K\8l(B") . "xe$B$KF|K\8l(B") 199;; (("$B$3(Bh$B$s(Be$B$K(Bl$B$A(Bl$B$O(Bo" 13 4 ?x "$BF|K\8l(B") . "xex$BF|K\8l(B") 200;; )) 201;; (let (ret) 202;; (condition-case e 203;; (setq ret (apply #'truncate-string-to-width (car test))) 204;; (error (setq ret e))) 205;; (unless (equal ret (cdr test)) 206;; (error "%s: expected %s, got %s" 207;; (prin1-to-string (cons 'truncate-string-to-width (car test))) 208;; (prin1-to-string (cdr test)) 209;; (if (consp ret) 210;; (format "error: %s: %s" (car ret) 211;; (prin1-to-string (cdr ret))) 212;; (prin1-to-string ret)))))) 213 214 215;;; Nested alist handler. Nested alist is alist whose elements are 216;;; also nested alist. 217 218;;;###autoload 219(defsubst nested-alist-p (obj) 220 "Return t if OBJ is a nested alist. 221 222Nested alist is a list of the form (ENTRY . BRANCHES), where ENTRY is 223any Lisp object, and BRANCHES is a list of cons cells of the form 224\(KEY-ELEMENT . NESTED-ALIST). 225 226You can use a nested alist to store any Lisp object (ENTRY) for a key 227sequence KEYSEQ, where KEYSEQ is a sequence of KEY-ELEMENT. KEYSEQ 228can be a string, a vector, or a list." 229 (and obj (listp obj) (listp (cdr obj)))) 230 231;;;###autoload 232(defun set-nested-alist (keyseq entry alist &optional len branches) 233 "Set ENTRY for KEYSEQ in a nested alist ALIST. 234Optional 4th arg LEN non-nil means the first LEN elements in KEYSEQ 235 is considered. 236Optional argument BRANCHES if non-nil is branches for a keyseq 237longer than KEYSEQ. 238See the documentation of `nested-alist-p' for more detail." 239 (or (nested-alist-p alist) 240 (error "Invalid argument %s" alist)) 241 (let ((islist (listp keyseq)) 242 (len (or len (length keyseq))) 243 (i 0) 244 key-elt slot) 245 (while (< i len) 246 (if (null (nested-alist-p alist)) 247 (error "Keyseq %s is too long for this nested alist" keyseq)) 248 (setq key-elt (if islist (nth i keyseq) (aref keyseq i))) 249 (setq slot (assoc key-elt (cdr alist))) 250 (if (null slot) 251 (progn 252 (setq slot (cons key-elt (list t))) 253 (setcdr alist (cons slot (cdr alist))))) 254 (setq alist (cdr slot)) 255 (setq i (1+ i))) 256 (setcar alist entry) 257 (if branches 258 (setcdr (last alist) branches)))) 259 260;;;###autoload 261(defun lookup-nested-alist (keyseq alist &optional len start nil-for-too-long) 262 "Look up key sequence KEYSEQ in nested alist ALIST. Return the definition. 263Optional 1st argument LEN specifies the length of KEYSEQ. 264Optional 2nd argument START specifies index of the starting key. 265The returned value is normally a nested alist of which 266car part is the entry for KEYSEQ. 267If ALIST is not deep enough for KEYSEQ, return number which is 268 how many key elements at the front of KEYSEQ it takes 269 to reach a leaf in ALIST. 270Optional 3rd argument NIL-FOR-TOO-LONG non-nil means return nil 271 even if ALIST is not deep enough." 272 (or (nested-alist-p alist) 273 (error "Invalid argument %s" alist)) 274 (or len 275 (setq len (length keyseq))) 276 (let ((i (or start 0))) 277 (if (catch 'lookup-nested-alist-tag 278 (if (listp keyseq) 279 (while (< i len) 280 (if (setq alist (cdr (assoc (nth i keyseq) (cdr alist)))) 281 (setq i (1+ i)) 282 (throw 'lookup-nested-alist-tag t)))) 283 (while (< i len) 284 (if (setq alist (cdr (assoc (aref keyseq i) (cdr alist)))) 285 (setq i (1+ i)) 286 (throw 'lookup-nested-alist-tag t)))) 287 ;; KEYSEQ is too long. 288 (if nil-for-too-long nil i) 289 alist))) 290 291 292;; Coding system related functions. 293 294;;;###autoload 295(defun coding-system-post-read-conversion (coding-system) 296 "Return the value of CODING-SYSTEM's `post-read-conversion' property." 297 (coding-system-get coding-system 'post-read-conversion)) 298 299;;;###autoload 300(defun coding-system-pre-write-conversion (coding-system) 301 "Return the value of CODING-SYSTEM's `pre-write-conversion' property." 302 (coding-system-get coding-system 'pre-write-conversion)) 303 304;;;###autoload 305(defun coding-system-translation-table-for-decode (coding-system) 306 "Return the value of CODING-SYSTEM's `translation-table-for-decode' property." 307 (coding-system-get coding-system 'translation-table-for-decode)) 308 309;;;###autoload 310(defun coding-system-translation-table-for-encode (coding-system) 311 "Return the value of CODING-SYSTEM's `translation-table-for-encode' property." 312 (coding-system-get coding-system 'translation-table-for-encode)) 313 314;;;###autoload 315(defmacro detect-coding-with-priority (from to priority-list) 316 "Detect a coding system of the text between FROM and TO with PRIORITY-LIST. 317PRIORITY-LIST is an alist of coding categories vs the corresponding 318coding systems ordered by priority." 319 `(unwind-protect 320 (let* ((prio-list ,priority-list) 321 (coding-category-list coding-category-list) 322 ,@(mapcar (function (lambda (x) (list x x))) 323 coding-category-list)) 324 (mapc (function (lambda (x) (set (car x) (cdr x)))) 325 prio-list) 326 (set-coding-priority (mapcar #'car prio-list)) 327 ;; Changing the binding of a coding category requires this call. 328 (update-coding-systems-internal) 329 (detect-coding-region ,from ,to)) 330 ;; We must restore the internal database. 331 (set-coding-priority coding-category-list) 332 (update-coding-systems-internal))) 333 334;;;###autoload 335(defun detect-coding-with-language-environment (from to lang-env) 336 "Detect a coding system of the text between FROM and TO with LANG-ENV. 337The detection takes into account the coding system priorities for the 338language environment LANG-ENV." 339 (let ((coding-priority (get-language-info lang-env 'coding-priority))) 340 (if coding-priority 341 (detect-coding-with-priority 342 from to 343 (mapcar (function (lambda (x) 344 (cons (coding-system-get x 'coding-category) x))) 345 coding-priority)) 346 (detect-coding-region from to)))) 347 348;;;###autoload 349(defun char-displayable-p (char) 350 "Return non-nil if we should be able to display CHAR. 351On a multi-font display, the test is only whether there is an 352appropriate font from the selected frame's fontset to display CHAR's 353charset in general. Since fonts may be specified on a per-character 354basis, this may not be accurate." 355 (cond ((< char 256) 356 ;; Single byte characters are always displayable. 357 t) 358 ((not enable-multibyte-characters) 359 ;; Maybe there's a font for it, but we can't put it in the buffer. 360 nil) 361 ((display-multi-font-p) 362 ;; On a window system, a character is displayable if we have 363 ;; a font for that character in the default face of the 364 ;; currently selected frame. 365 (car (internal-char-font nil char))) 366 (t 367 (let ((coding (terminal-coding-system))) 368 (if coding 369 (let ((safe-chars (coding-system-get coding 'safe-chars)) 370 (safe-charsets (coding-system-get coding 'safe-charsets))) 371 (or (and safe-chars 372 (aref safe-chars char)) 373 (and safe-charsets 374 (memq (char-charset char) safe-charsets))))))))) 375 376(provide 'mule-util) 377 378;; Local Variables: 379;; coding: iso-2022-7bit 380;; End: 381 382;; arch-tag: 5bdb52b6-a3a5-4529-b7a0-37d01b0e570b 383;;; mule-util.el ends here 384