X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/5d74f2a65c0e8e67e5933d1f47e2b9413fd84646..22cc6690e717501adc7dcbb19ec910a4009e92ca:/lisp/disp-table.el

diff --git a/lisp/disp-table.el b/lisp/disp-table.el
index b15bc7fed1..d75dd41e70 100644
--- a/lisp/disp-table.el
+++ b/lisp/disp-table.el
@@ -1,8 +1,9 @@
 ;;; disp-table.el --- functions for dealing with char tables.
 
-;; Copyright (C) 1987, 1994 Free Software Foundation, Inc.
+;; Copyright (C) 1987, 1994, 1995 Free Software Foundation, Inc.
 
-;; Author: Howard Gayle
+;; Author: Erik Naggum <erik@naggum.no>
+;; Based on a previous version by Howard Gayle
 ;; Maintainer: FSF
 ;; Keywords: i18n
 
@@ -24,24 +25,65 @@
 
 ;;; Code:
 
-(defconst display-table-len 262
-  "The proper length of a display table.")
+(put 'display-table 'char-table-extra-slots 6)
 
+;;;###autoload
+(defun make-display-table ()
+  "Return a new, empty display table."
+  (make-char-table 'display-table nil))
+
+(or standard-display-table
+    (setq standard-display-table (make-display-table)))
+
+;;; Display-table slot names.  The property value says which slot.
+
+(put 'truncation 'display-table-slot 0)
+(put 'wrap 'display-table-slot 1)
+(put 'escape 'display-table-slot 2)
+(put 'control 'display-table-slot 3)
+(put 'selective-display 'display-table-slot 4)
+(put 'vertical-border 'display-table-slot 5)
+
+;;;###autoload
+(defun display-table-slot (display-table slot)
+  "Return the value of the extra slot in DISPLAY-TABLE named SLOT.
+SLOT may be a number from 0 to 5 inclusive, or a slot name (symbol).
+Valid symbols are `truncation', `wrap', `escape', `control',
+`selective-display', and `vertical-border'."
+  (let ((slot-number
+	 (if (numberp slot) slot
+	   (or (get slot 'display-table-slot)
+	       (error "Invalid display-table slot name: %s" slot)))))
+    (char-table-extra-slot display-table slot-number)))
+
+;;;###autoload
+(defun set-display-table-slot (display-table slot value)
+  "Set the value of the extra slot in DISPLAY-TABLE named SLOT to VALUE.
+SLOT may be a number from 0 to 5 inclusive, or a name (symbol).
+Valid symbols are `truncation', `wrap', `escape', `control',
+`selective-display', and `vertical-border'."
+  (let ((slot-number
+	 (if (numberp slot) slot
+	   (or (get slot 'display-table-slot)
+	       (error "Invalid display-table slot name: %s" slot)))))
+    (set-char-table-extra-slot display-table slot-number value)))
+
+;;;###autoload
 (defun describe-display-table (dt)
   "Describe the display table DT in a help buffer."
   (with-output-to-temp-buffer "*Help*"
     (princ "\nTruncation glyph: ")
-    (prin1 (aref dt 256))
+    (prin1 (display-table-slot dt 'truncation))
     (princ "\nWrap glyph: ")
-    (prin1 (aref dt 257))
+    (prin1 (display-table-slot dt 'wrap))
     (princ "\nEscape glyph: ")
-    (prin1 (aref dt 258))
+    (prin1 (display-table-slot dt 'escape))
     (princ "\nCtrl glyph: ")
-    (prin1 (aref dt 259))
+    (prin1 (display-table-slot dt 'control))
     (princ "\nSelective display glyph sequence: ")
-    (prin1 (aref dt 260))
+    (prin1 (display-table-slot dt 'selective-display))
     (princ "\nVertical window border glyph: ")
-    (prin1 (aref dt 261))
+    (prin1 (display-table-slot dt 'vertical-border))
     (princ "\nCharacter display glyph sequences:\n")
     (save-excursion
       (set-buffer standard-output)
@@ -58,27 +100,19 @@
 (defun describe-current-display-table ()
   "Describe the display table in use in the selected window and buffer."
   (interactive)
-  (let ((disptab
-	 (or (window-display-table (selected-window))
-	     buffer-display-table
-	     standard-display-table)))
+  (let ((disptab (or (window-display-table (selected-window))
+		     buffer-display-table
+		     standard-display-table)))
     (if disptab
 	(describe-display-table disptab)
       (message "No display table"))))
 
-;;;###autoload
-(defun make-display-table ()
-  "Return a new, empty display table."
-  (make-vector display-table-len nil))
-
 ;;;###autoload
 (defun standard-display-8bit (l h)
   "Display characters in the range L to H literally."
   (while (<= l h)
     (if (and (>= l ?\ ) (< l 127))
-	(if standard-display-table (aset standard-display-table l nil))
-      (or standard-display-table
-	  (setq standard-display-table (make-vector display-table-len nil)))
+	(aset standard-display-table l nil)
       (aset standard-display-table l (vector l)))
     (setq l (1+ l))))
 
@@ -87,22 +121,17 @@
   "Display characters in the range L to H using the default notation."
   (while (<= l h)
     (if (and (>= l ?\ ) (< l 127))
-	(if standard-display-table (aset standard-display-table l nil))
-      (or standard-display-table
-	  (setq standard-display-table (make-vector display-table-len nil)))
+	(aset standard-display-table l nil)
       (aset standard-display-table l nil))
     (setq l (1+ l))))
 
+;; This function does NOT take terminal-dependent escape sequences.
+;; For that, you need to go through create-glyph.  Use one of the
+;; other functions below, or roll your own.
 ;;;###autoload
 (defun standard-display-ascii (c s)
-  "Display character C using string S.
-S is usually a terminal-dependent escape sequence.
-This function is meaningless for an X frame."
-  (if window-system
-      (error "Cannot use string glyphs in a windowing system"))
-  (or standard-display-table
-      (setq standard-display-table (make-vector display-table-len nil)))
-  (aset standard-display-table c (apply 'vector (append s nil))))
+  "Display character C using printable string S."
+  (aset standard-display-table c (vconcat s)))
 
 ;;;###autoload
 (defun standard-display-g1 (c sc)
@@ -111,8 +140,6 @@ This function assumes that your terminal uses the SO/SI characters;
 it is meaningless for an X frame."
   (if window-system
       (error "Cannot use string glyphs in a windowing system"))
-  (or standard-display-table
-      (setq standard-display-table (make-vector display-table-len nil)))
   (aset standard-display-table c
 	(vector (create-glyph (concat "\016" (char-to-string sc) "\017")))))
 
@@ -123,8 +150,6 @@ This function assumes VT100-compatible escapes; it is meaningless for an
 X frame."
   (if window-system
       (error "Cannot use string glyphs in a windowing system"))
-  (or standard-display-table
-      (setq standard-display-table (make-vector display-table-len nil)))
   (aset standard-display-table c
 	(vector (create-glyph (concat "\e(0" (char-to-string gc) "\e(B")))))
 
@@ -132,8 +157,6 @@ X frame."
 (defun standard-display-underline (c uc)
   "Display character C as character UC plus underlining."
   (if window-system (require 'faces))
-  (or standard-display-table
-      (setq standard-display-table (make-vector display-table-len nil)))
   (aset standard-display-table c
 	(vector 
 	 (if window-system
@@ -160,11 +183,14 @@ With prefix argument, enable European character display iff arg is positive."
   (interactive "P")
   (if (or (<= (prefix-numeric-value arg) 0)
 	  (and (null arg)
-	       (vectorp standard-display-table)
-	       (>= (length standard-display-table) 161)
-	       (equal (aref standard-display-table 160) [160])))
+	       (char-table-p standard-display-table)
+	       ;; Test 161, because 160 displays as a space.
+	       (equal (aref standard-display-table 161) [161])))
       (standard-display-default 160 255)
-    (standard-display-8bit 160 255)))
+    (standard-display-8bit 160 255)
+    ;; Make non-line-break space display as a plain space.
+    ;; Most X fonts do the wrong thing for code 160.
+    (aset standard-display-table 160 [32])))
 
 (provide 'disp-table)