#name : find and replace on region
#contributor : Xah Lee
# --
(defun replace-html-chars-region (start end)
  "Replace “<” to “&lt;” and other chars in HTML.
This works on the current region."
  (interactive "r")
  (save-restriction 
    (narrow-to-region start end)
    (goto-char (point-min))
    (while (search-forward "&" nil t) (replace-match "&amp;" nil t))
    (goto-char (point-min))
    (while (search-forward "<" nil t) (replace-match "&lt;" nil t))
    (goto-char (point-min))
    (while (search-forward ">" nil t) (replace-match "&gt;" nil t))
    )
  )