* lisp/isearch.el: Let M-e start with point at the first mismatched char.

(isearch-fail-pos): New function.
(isearch-edit-string): Use it.

lisp/ChangeLog

@@ -1,3 +1,9 @@
+2011-05-28  Drew Adams  <drew.adams@oracle.com>
+
+	* isearch.el: Let M-e start with point at the first mismatched char.
+	(isearch-fail-pos): New function.
+	(isearch-edit-string): Use it.
+
 2011-05-28  Dmitry Kurochkin  <dmitry.kurochkin@gmail.com>  (tiny change)
 
 	* isearch.el (isearch-range-invisible): Use invisible-p (bug#8721).

lisp/isearch.el

@@ -1062,6 +1062,22 @@ nonincremental search instead via `isearch-edit-string'."
 
 (defvar minibuffer-history-symbol) ;; from external package gmhist.el
 
+(defun isearch-fail-pos ()
+  "Position of first mismatch in search string, or its length if none."
+  (let ((cmds isearch-cmds))
+    (if (and isearch-success (not isearch-error))
+        (length isearch-message)
+      (while (or (not (isearch-success-state (car cmds)))
+                 (isearch-error-state (car cmds)))
+        (pop cmds))
+      (let ((succ-msg (and cmds (isearch-message-state (car cmds)))))
+        (if (and (stringp succ-msg)
+                 (< (length succ-msg) (length isearch-message))
+                 (equal succ-msg
+                        (substring isearch-message 0 (length succ-msg))))
+            (length succ-msg)
+          0)))))
+
 (defun isearch-edit-string ()
   "Edit the search string in the minibuffer.
 The following additional command keys are active while editing.
@@ -1141,7 +1157,7 @@ If first char entered is \\[isearch-yank-word-or-char], then do word search inst
 		(setq isearch-new-string
                       (read-from-minibuffer
                        (isearch-message-prefix nil nil isearch-nonincremental)
-                       isearch-string
+                        (cons isearch-string (1+ (isearch-fail-pos)))
                        minibuffer-local-isearch-map nil
                        (if isearch-regexp
 			   (cons 'regexp-search-ring