title: How to replace a running function in Common Lisp?
body: <p>Suppose we use SBCL's #'save-lisp-and-die to create an server applicatioon App1, which works very well.  Now we want to replace a function #'func1 with a new version without stopping App1.   How can we do it in Common Lisp ?</p>
  
  <p>Any suggestion is appreciated !</p>