and-let* for Emacs LISP

and-let.el

(defmacro and-let* (bindings &rest body)
  (let ((head (car bindings))
        (rest (cdr bindings)))
    (cond
     ((null head)
      `(progn
         ,@body))
     ((and (null rest) (null body))
      (cond
       ((symbolp head)
        head)
       ((symbolp (car head))
        (let ((exp (cadr head)))
          exp))
       ((listp (car head))
        (let ((exp (car head)))
          exp))))
     ((symbolp head)
      `(if ,head
           (and-let* ,rest ,@body)
         nil))
     ((symbolp (car head))
      (let ((var (car head))
            (exp (cadr head))
            (tmp-var (gensym)))
        `(let ((,tmp-var ,exp))
           (if ,tmp-var
               (let ((,var ,tmp-var))
                 ,(if (and (null rest) (null body))
                      var
                    `(and-let* ,rest ,@body)))
             nil))))
     ((listp (car head))
      (let ((exp (car head)))
        `(if ,exp
             (and-let* ,rest ,@body)
           nil)))
     (t
      nil))))