[racket] Are there any papers that explain Code/Structure Inspectors?

At Sun, 24 Jun 2012 15:14:12 -0700, Ian Tegebo wrote:
> I was playing with #lang racket/gui, and then did,
> 
> > (class-info button%)
> class-info: current inspector cannot inspect class: #<class:button%>
> 
> Reading a bit of the reference manual turned up both "code" and
> "structure" inspectors, but I'm not sure how to solve my particular
> problem.  That aside, are there any papers that introduce
> "inspectors"?

No. There are no such papers, yet, although there should be.

To inspect `button%', you'd need to set the inspector before loading
`racket/gui':

 > (define i (current-inspector))
 > (current-inspector (make-inspector))
 > (require racket/gui)
 > (class-info button%)
 class-info: current inspector cannot inspect class
   class: #<class:button%>
   context...:
    /Users/mflatt/proj/plt/collects/racket/private/misc.rkt:87:7
 > (current-inspector i)
 > (class-info button%)
 'button%
 0
 '()
 'field-ref
 'field-set!
 #<class:basic-control%>
 #f
 > 

The intent is that `button%' is opaque to clients of `racket/gui'.
Setting the inspector before loading `racket/gui' is stepping outside
the system and taking extra control to, say, debug `racket/gui' itself.