(hide-ifdef-syntax-table): New variable.

(hif-tokenize): Use it.
(hide-ifdef-mode): Don't clobber `c-mode-syntax-table'.

diff --git a/lisp/progmodes/hideif.el b/lisp/progmodes/hideif.el
index ee7ff90da487c67cced941050d8d3c02bd046d7b..59bdd215861e6830a364ab950d2cba9a38ef56f3 100644 (file)
--- a/lisp/progmodes/hideif.el
+++ b/lisp/progmodes/hideif.el
@@ -205,6 +205,15 @@
           (cons '(hide-ifdef-mode " Ifdef")
                 minor-mode-alist)))
 
+;; fix c-mode syntax table so we can recognize whole symbols.
+(defvar hide-ifdef-syntax-table
+  (copy-syntax-table c-mode-syntax-table)
+  "Syntax table used for tokenizing #if expressions.")
+
+(modify-syntax-entry ?_ "w" hide-ifdef-syntax-table)
+(modify-syntax-entry ?& "." hide-ifdef-syntax-table)
+(modify-syntax-entry ?\| "." hide-ifdef-syntax-table)
+
 ;;;###autoload
 (defun hide-ifdef-mode (arg)
   "Toggle Hide-Ifdef mode.  This is a minor mode, albeit a large one.
@@ -249,11 +258,6 @@ hide-ifdef-read-only
 
   (if hide-ifdef-mode
       (progn
-       ; fix c-mode syntax table so we can recognize whole symbols.
-       (modify-syntax-entry ?_ "w")
-       (modify-syntax-entry ?& ".")
-       (modify-syntax-entry ?\| ".")
-
        ; inherit global values
        (make-local-variable 'hide-ifdef-env)
        (setq hide-ifdef-env (default-value 'hide-ifdef-env))
@@ -376,55 +380,54 @@ that form should be displayed.")
   "Separate string into a list of tokens"
   (let ((token-list nil)
        (expr-start 0)
-       (expr-length (length expr-string)))
-
-    (while (< expr-start expr-length) 
-;      (message "expr-start = %d" expr-start) (sit-for 1)
-      (cond
-       ((string-match "^[ \t]+" expr-string expr-start)
-          ; skip whitespace
-        (setq expr-start (match-end 0))
-        ; stick newline in string so ^ matches on the next string-match
-        (aset expr-string (1- expr-start) ?\n)
-        )
-
-       ((string-match "^/\\*" expr-string expr-start)
-        (setq expr-start (match-end 0))
-        (aset expr-string (1- expr-start) ?\n)
-        (or
-          (string-match hif-end-of-comment
-                        expr-string expr-start) ; eat comment
-          (string-match "$" expr-string expr-start)) ; multi-line comment
-        (setq expr-start (match-end 0))
-        (aset expr-string (1- expr-start) ?\n)
-        )
-
-       ((string-match "^//" expr-string expr-start)
-        (string-match "$" expr-string expr-start)
-        (setq expr-start (match-end 0))
-        )
-
-       ((string-match hif-token-regexp expr-string expr-start)
-         (let ((token (substring expr-string expr-start (match-end 0))))
-           (setq expr-start (match-end 0))
-           (aset expr-string (1- expr-start) ?\n)
-;          (message "token: %s" token) (sit-for 1)
-           (setq token-list
-                 (cons
-                   (cond
-                     ((string-equal token "||") 'or)
-                     ((string-equal token "&&") 'and)
-                     ((string-equal token "!")  'not)
-                     ((string-equal token "defined") 'hif-defined)
-                     ((string-equal token "(") 'lparen)
-                     ((string-equal token ")") 'rparen)
-                     (t (intern token)))
-                   token-list))
-           ))
-         (t (error "Bad #if expression: %s" expr-string))
-         ))
-    (nreverse token-list)
-    ))
+       (expr-length (length expr-string))
+       (current-syntax-table (syntax-table)))
+    (unwind-protect
+       (progn
+         (set-syntax-table hide-ifdef-syntax-table)
+         (while (< expr-start expr-length) 
+;          (message "expr-start = %d" expr-start) (sit-for 1)
+           (cond
+            ((string-match "^[ \t]+" expr-string expr-start)
+             ;; skip whitespace
+             (setq expr-start (match-end 0))
+             ;; stick newline in string so ^ matches on the next string-match
+             (aset expr-string (1- expr-start) ?\n))
+
+            ((string-match "^/\\*" expr-string expr-start)
+             (setq expr-start (match-end 0))
+             (aset expr-string (1- expr-start) ?\n)
+             (or
+              (string-match hif-end-of-comment
+                            expr-string expr-start) ; eat comment
+              (string-match "$" expr-string expr-start)) ; multi-line comment
+             (setq expr-start (match-end 0))
+             (aset expr-string (1- expr-start) ?\n))
+
+            ((string-match "^//" expr-string expr-start)
+             (string-match "$" expr-string expr-start)
+             (setq expr-start (match-end 0)))
+
+            ((string-match hif-token-regexp expr-string expr-start)
+             (let ((token (substring expr-string expr-start (match-end 0))))
+               (setq expr-start (match-end 0))
+               (aset expr-string (1- expr-start) ?\n)
+;              (message "token: %s" token) (sit-for 1)
+               (setq token-list
+                     (cons
+                      (cond
+                       ((string-equal token "||") 'or)
+                       ((string-equal token "&&") 'and)
+                       ((string-equal token "!")  'not)
+                       ((string-equal token "defined") 'hif-defined)
+                       ((string-equal token "(") 'lparen)
+                       ((string-equal token ")") 'rparen)
+                       (t (intern token)))
+                      token-list))))
+
+            (t (error "Bad #if expression: %s" expr-string)))))
+      (set-syntax-table current-syntax-table))
+    (nreverse token-list)))
 
 ;;;-----------------------------------------------------------------
 ;;; Translate C preprocessor #if expressions using recursive descent.