(beginning-of-defun)
(re-search-backward "^\n" (- (point) 1) t))
+(defun narrow-to-defun (&optional arg)
+ "Make text outside current defun invisible.
+The defun visible is the one that contains point or follows point."
+ (interactive)
+ (save-excursion
+ (widen)
+ (beginning-of-defun)
+ (narrow-to-region (point) (progn (end-of-defun) (point)))))
+
(defun insert-parentheses (arg)
"Put parentheses around next ARG sexps. Leave point after open-paren.
No argument is equivalent to zero: just insert `()' and leave point between.