;;;; Make a macro that is like C's printf statement

(defmacro printf (string &rest vars)
  "Pretend to be printf... except preceding dec places"
  `(format t ,(printf-to-format string) ,@vars))

(defun replace-all (string part replacement &key (test #'char=))
  "Returns a new string in which all the occurences of the part 
is replaced with replacement."
  (with-output-to-string (out)
    (loop with part-length = (length part)
          for old-pos = 0 then (+ pos part-length)
          for pos = (search part string
                            :start2 old-pos
                            :test test)
          do (write-string string out
                           :start old-pos
                           :end (or pos (length string)))
          when pos do (write-string replacement out)
          while pos)))

(defun printf-to-format (string &optional
				  (printf-format '("%s" "%d" "%x" "%f" "%u" "\n"))
				  (lisp-format '("~A" "~D" "~X" "~F" "~D" "~%")))
  "Convert printf sytax to format syntax"
  (cond ((NULL printf-format) (return-from printf-to-format string))
	(T (printf-to-format (replace-all string
					  (car printf-format)
					  (car lisp-format))
			     (cdr printf-format)
			     (cdr lisp-format)))))