LISP provides a function, defstruct, which creates a data structure and functions for accessing various fields in it. This can be useful, so I'm doing something similar here.

(defstruct book title author subject book-id )

~~~{{   :make-helper (nsq-)  [ d:create , ] dip does ;   :make-struct (ns-)   d:create , [ here swap fetch allot ] does ; ---reveal---   :defstruct (sa-)     dup a:length     [ n:dec swap       [ 'ab 'aabab reorder         '@ s:append [ fetch + fetch ] make-helper         '! s:append [ fetch + store ] make-helper         n:dec       ] a:for-each drop     ] sip swap make-struct ; }} ~~~

```'book { 'title 'author 'subject 'book-id } defstruct   book 'A const 'The_Hobbit     s:keep &A title! 'J.R.R._Tolkien s:keep &A author! 'Fantasy        s:keep &A subject!   :info (a-)   [ subject@ ] [ author@ ] [ title@ ] tri   '%s_by_%s_is_a_%s_book. s:format s:put nl ;   &A info ```