(set-dispatch-macro-character #\# #\{
  (lambda (s c n)
    (declare (ignore c n))
    `'(run-in-language
       ,(with-output-to-string (s*)
          (loop with maybe-} = nil
                for char = (read-char s)
                do (cond
                    ((char= #\} char)
                     (setf maybe-} t))
                    ((and maybe-} (char= #\# char))
                     (return))
                    (t
                     (setf maybe-} nil)
                     (write-char char s*))))))))