On Tue, 5 Nov 2002, Ville Skyttä wrote: Ah. I don't actually have 21.4.10 at the moment, and I've only a modem with which to get it. I don't really want to delve too deeply into XEmacs's C-code myself. But... Forgive me for reporting this bug without providing a recipe for recreating it. That I will now do. 1. Compile the following function: (defun bsc-bug-after-change (beg end old-len) "After-change function for demonstrating a buffer-syntactic-context bug. Start off by wiping syntax-table text-properties from the line. If there is a matched pair of /s, give each of them s-t prop (7) (i.e. \"string\"). If there is a _single_ /, give it (and any eol) s-t prop (15) (i.e. \"string-fence\")." (save-excursion (save-match-data (let ((eol (progn (goto-char end) (end-of-line) (point)))) (goto-char beg) (beginning-of-line) (put-text-property (point) eol 'syntax-table nil) (cond ((search-forward-regexp "\\(/\\)[^/]*\\(/\\)" eol t) (put-text-property (match-beginning 1) (match-end 1) 'syntax-table '(7)) (put-text-property (match-beginning 2) (match-end 2) 'syntax-table '(7))) ((search-forward-regexp "/" eol t) (put-text-property (match-beginning 0) (match-end 0) 'syntax-table '(15)) (if (eq (char-after eol) ?\n) (put-text-property eol (1+ eol) 'syntax-table '(15)))) (t)))))) 2: Create an empty buffer in fundamental mode. 3: Enable syntax-table properties: (make-local-variable 'lookup-syntax-properties) (setq lookup-syntax-properties t) 4: Install the after-change-function for this buffer: (make-local-hook 'after-change-functions) (add-hook 'after-change-functions 'bsc-bug-after-change nil t) 5: Type the following, character by character, into the buffer: /regexp/ { (with or without a CR at the eol). 6: Place the cursor on the {, and do M-: (buffer-syntactic-context). The result is 'string; it ought to be nil. As I said, I suspect the reason for this result is that some sort of cacheing mechanism in b-s-c has remembered that the first / has string-fence syntax although its updated syntax is now string. -- Alan Mackenzie (Munich, Germany)