parameter string;
storage string;
return string;
code {DUP;                      # We're going to need both the storage and parameter
      CAR;                      # Get the parameter
      DIP{CDR;                  # Get the storage value
          DUP};                 # We need to replace it in the storage, so we dup it
      SWAP;                     # Get the order we want (this is optional)
      CONCAT;                   # Concatenate the strings
      PAIR}                     # Pair them up, matching the calling convention