(symbol-under-point, symbol-before-point)

(symbol-under-or-before-point, symbol-before-point-for-complete):
Use unwind-protect to restore syntax table.
(symbol-before-point, symbol-before-point-for-complete):
Start the backward scan-sexps from point, not (1+ (point)).

diff --git a/lisp/completion.el b/lisp/completion.el
index 55c65a92015bad13c79b77552607d116f56cd1be..a4e066f21cede15aa8e91d75f325b0e792c2d4a9 100644 (file)
--- a/lisp/completion.el
+++ b/lisp/completion.el
@@ -618,41 +618,36 @@ Used to decide whether to save completions.")
   "Returns the symbol that the point is currently on.
 But only if it is longer than `completion-min-length'."
   (setq cmpl-saved-syntax (syntax-table))
-  (set-syntax-table cmpl-syntax-table)
-  (cond 
-  ;; Cursor is on following-char and after preceding-char
-    ((memq (char-syntax (following-char)) '(?w ?_))     
-     (setq cmpl-saved-point (point)
-          cmpl-symbol-start (scan-sexps (1+ cmpl-saved-point) -1)
-          cmpl-symbol-end (scan-sexps cmpl-saved-point 1))
-     ;; remove chars to ignore at the start
-     (cond ((= (char-syntax (char-after cmpl-symbol-start)) ?w)
-           (goto-char cmpl-symbol-start)
-           (forward-word 1)
-           (setq cmpl-symbol-start (point))
-           (goto-char cmpl-saved-point)
-           ))
-     ;; remove chars to ignore at the end
-     (cond ((= (char-syntax (char-after (1- cmpl-symbol-end))) ?w)
-           (goto-char cmpl-symbol-end)
-           (forward-word -1)
-           (setq cmpl-symbol-end (point))
-           (goto-char cmpl-saved-point)
-           ))
-     ;; restore state
-     (set-syntax-table cmpl-saved-syntax)
-     ;; Return completion if the length is reasonable
-     (if (and (<= (cmpl-read-time-eval completion-min-length)
-                 (- cmpl-symbol-end cmpl-symbol-start))
-             (<= (- cmpl-symbol-end cmpl-symbol-start)
-                 (cmpl-read-time-eval completion-max-length)))
-        (buffer-substring cmpl-symbol-start cmpl-symbol-end))
-     )
-    (t 
-     ;; restore table if no symbol
-     (set-syntax-table cmpl-saved-syntax)
-     nil)
-    ))
+  (unwind-protect
+      (progn
+       (set-syntax-table cmpl-syntax-table)
+       (cond 
+       ;; Cursor is on following-char and after preceding-char
+         ((memq (char-syntax (following-char)) '(?w ?_))     
+          (setq cmpl-saved-point (point)
+                cmpl-symbol-start (scan-sexps (1+ cmpl-saved-point) -1)
+                cmpl-symbol-end (scan-sexps cmpl-saved-point 1))
+          ;; Remove chars to ignore at the start.
+          (cond ((= (char-syntax (char-after cmpl-symbol-start)) ?w)
+                 (goto-char cmpl-symbol-start)
+                 (forward-word 1)
+                 (setq cmpl-symbol-start (point))
+                 (goto-char cmpl-saved-point)
+                 ))
+          ;; Remove chars to ignore at the end.
+          (cond ((= (char-syntax (char-after (1- cmpl-symbol-end))) ?w)
+                 (goto-char cmpl-symbol-end)
+                 (forward-word -1)
+                 (setq cmpl-symbol-end (point))
+                 (goto-char cmpl-saved-point)
+                 ))
+          ;; Return completion if the length is reasonable.
+          (if (and (<= (cmpl-read-time-eval completion-min-length)
+                       (- cmpl-symbol-end cmpl-symbol-start))
+                   (<= (- cmpl-symbol-end cmpl-symbol-start)
+                       (cmpl-read-time-eval completion-max-length)))
+              (buffer-substring cmpl-symbol-start cmpl-symbol-end)))))
+    (set-syntax-table cmpl-saved-syntax)))
 
 ;;; tests for symbol-under-point
 ;;;  `^' indicates cursor pos. where value is returned
@@ -671,56 +666,50 @@ But only if it is longer than `completion-min-length'."
 Returns nil if there isn't one longer than `completion-min-length'."       
   ;; This is called when a word separator is typed so it must be FAST !
   (setq cmpl-saved-syntax (syntax-table))
-  (set-syntax-table cmpl-syntax-table)
-  ;; Cursor is on following-char and after preceding-char
-  (cond ((= (setq cmpl-preceding-syntax (char-syntax (preceding-char))) ?_)
-        ;; No chars. to ignore at end
-        (setq cmpl-symbol-end (point)
-              cmpl-symbol-start (scan-sexps (1+ cmpl-symbol-end) -1)
+  (unwind-protect
+      (progn
+       (set-syntax-table cmpl-syntax-table)
+       ;; Cursor is on following-char and after preceding-char
+       (cond ((= (setq cmpl-preceding-syntax (char-syntax (preceding-char))) ?_)
+              ;; Number of chars to ignore at end.
+              (setq cmpl-symbol-end (point)
+                    cmpl-symbol-start (scan-sexps cmpl-symbol-end -1)
+                    )
+              ;; Remove chars to ignore at the start.
+              (cond ((= (char-syntax (char-after cmpl-symbol-start)) ?w)
+                     (goto-char cmpl-symbol-start)
+                     (forward-word 1)
+                     (setq cmpl-symbol-start (point))
+                     (goto-char cmpl-symbol-end)
+                     ))
+              ;; Return value if long enough.
+              (if (>= cmpl-symbol-end
+                      (+ cmpl-symbol-start
+                         (cmpl-read-time-eval completion-min-length)))
+                  (buffer-substring cmpl-symbol-start cmpl-symbol-end))
               )
-        ;; remove chars to ignore at the start
-        (cond ((= (char-syntax (char-after cmpl-symbol-start)) ?w)
-               (goto-char cmpl-symbol-start)
-               (forward-word 1)
-               (setq cmpl-symbol-start (point))
-               (goto-char cmpl-symbol-end)
-               ))
-        ;; restore state
-        (set-syntax-table cmpl-saved-syntax)
-        ;; return value if long enough
-        (if (>= cmpl-symbol-end
-                (+ cmpl-symbol-start
-                   (cmpl-read-time-eval completion-min-length)))
-            (buffer-substring cmpl-symbol-start cmpl-symbol-end))
-        )
-       ((= cmpl-preceding-syntax ?w)
-        ;; chars to ignore at end
-        (setq cmpl-saved-point (point)
-              cmpl-symbol-start (scan-sexps (1+ cmpl-saved-point) -1))
-        ;; take off chars. from end
-        (forward-word -1)
-        (setq cmpl-symbol-end (point))
-        ;; remove chars to ignore at the start
-        (cond ((= (char-syntax (char-after cmpl-symbol-start)) ?w)
-               (goto-char cmpl-symbol-start)
-               (forward-word 1)
-               (setq cmpl-symbol-start (point))
-               ))
-        ;; restore state
-        (goto-char cmpl-saved-point)
-        (set-syntax-table cmpl-saved-syntax)
-        ;; Return completion if the length is reasonable
-        (if (and (<= (cmpl-read-time-eval completion-min-length)
-                     (- cmpl-symbol-end cmpl-symbol-start))
-                 (<= (- cmpl-symbol-end cmpl-symbol-start)
-                     (cmpl-read-time-eval completion-max-length)))
-            (buffer-substring cmpl-symbol-start cmpl-symbol-end))
-        )
-       (t 
-        ;; restore table if no symbol
-        (set-syntax-table cmpl-saved-syntax)
-        nil)
-       ))
+             ((= cmpl-preceding-syntax ?w)
+              ;; chars to ignore at end
+              (setq cmpl-saved-point (point)
+                    cmpl-symbol-start (scan-sexps cmpl-saved-point -1))
+              ;; take off chars. from end
+              (forward-word -1)
+              (setq cmpl-symbol-end (point))
+              ;; remove chars to ignore at the start
+              (cond ((= (char-syntax (char-after cmpl-symbol-start)) ?w)
+                     (goto-char cmpl-symbol-start)
+                     (forward-word 1)
+                     (setq cmpl-symbol-start (point))
+                     ))
+              ;; Restore state.
+              (goto-char cmpl-saved-point)
+              ;; Return completion if the length is reasonable
+              (if (and (<= (cmpl-read-time-eval completion-min-length)
+                           (- cmpl-symbol-end cmpl-symbol-start))
+                       (<= (- cmpl-symbol-end cmpl-symbol-start)
+                           (cmpl-read-time-eval completion-max-length)))
+                  (buffer-substring cmpl-symbol-start cmpl-symbol-end)))))
+    (set-syntax-table cmpl-saved-syntax)))
 
 ;;; tests for symbol-before-point
 ;;;  `^' indicates cursor pos. where value is returned
@@ -741,15 +730,17 @@ Returns nil if there isn't one longer than `completion-min-length'."
   ;;; copying all the code.
   ;;; However, it is only used by the completion string prompter.
   ;;; If it comes into common use, it could be rewritten.
-  (setq cmpl-saved-syntax (syntax-table))
-  (set-syntax-table cmpl-syntax-table)
-  (cond ((memq (char-syntax (following-char)) '(?w ?_))
-        (set-syntax-table cmpl-saved-syntax)
+  (cond ((memq (progn
+                (setq cmpl-saved-syntax (syntax-table))
+                (unwind-protect
+                    (progn
+                      (set-syntax-table cmpl-syntax-table)
+                      (char-syntax (following-char)))
+                  (set-syntax-table cmpl-saved-syntax)))
+              '(?w ?_))
         (symbol-under-point))
        (t
-        (set-syntax-table cmpl-saved-syntax)
-        (symbol-before-point))
-       ))
+        (symbol-before-point))))
 
 
 (defun symbol-before-point-for-complete ()
@@ -758,34 +749,30 @@ Returns nil if there isn't one longer than `completion-min-length'."
   ;; end chars."
   ;; Cursor is on following-char and after preceding-char
   (setq cmpl-saved-syntax (syntax-table))
-  (set-syntax-table cmpl-syntax-table)
-  (cond ((memq (setq cmpl-preceding-syntax (char-syntax (preceding-char)))
-              '(?_ ?w))
-        (setq cmpl-symbol-end (point)
-              cmpl-symbol-start (scan-sexps (1+ cmpl-symbol-end) -1)
-              )
-        ;; remove chars to ignore at the start
-        (cond ((= (char-syntax (char-after cmpl-symbol-start)) ?w)
-               (goto-char cmpl-symbol-start)
-               (forward-word 1)
-               (setq cmpl-symbol-start (point))
-               (goto-char cmpl-symbol-end)
-               ))
-        ;; restore state
-        (set-syntax-table cmpl-saved-syntax)
-        ;; Return completion if the length is reasonable
-        (if (and (<= (cmpl-read-time-eval
-                      completion-prefix-min-length)
-                     (- cmpl-symbol-end cmpl-symbol-start))
-                 (<= (- cmpl-symbol-end cmpl-symbol-start)
-                     (cmpl-read-time-eval completion-max-length)))
-            (buffer-substring cmpl-symbol-start cmpl-symbol-end))
-        )
-       (t 
-        ;; restore table if no symbol
-        (set-syntax-table cmpl-saved-syntax)
-        nil)
-       ))
+  (unwind-protect
+      (progn
+       (set-syntax-table cmpl-syntax-table)
+       (cond ((memq (setq cmpl-preceding-syntax (char-syntax (preceding-char)))
+                    '(?_ ?w))
+              (setq cmpl-symbol-end (point)
+                    cmpl-symbol-start (scan-sexps cmpl-symbol-end -1)
+                    )
+              ;; Remove chars to ignore at the start.
+              (cond ((= (char-syntax (char-after cmpl-symbol-start)) ?w)
+                     (goto-char cmpl-symbol-start)
+                     (forward-word 1)
+                     (setq cmpl-symbol-start (point))
+                     (goto-char cmpl-symbol-end)
+                     ))
+              ;; Return completion if the length is reasonable.
+              (if (and (<= (cmpl-read-time-eval
+                            completion-prefix-min-length)
+                           (- cmpl-symbol-end cmpl-symbol-start))
+                       (<= (- cmpl-symbol-end cmpl-symbol-start)
+                           (cmpl-read-time-eval completion-max-length)))
+                  (buffer-substring cmpl-symbol-start cmpl-symbol-end)))))
+    ;; Restore syntax table.
+    (set-syntax-table cmpl-saved-syntax)))
 
 ;;; tests for symbol-before-point-for-complete
 ;;;  `^' indicates cursor pos. where value is returned