Figuring out enums and structs with foreigners

[Diogo via Chicken-users]

Dear mailing list,

I have a beginners question. Using `foreigners` one can easily define 
structs and enums. But how does one figure out whether a symbol is an
enum or a struct? 

Here is a small example of what I am trying to do:

```
(import (chicken base)
        (chicken foreign)
        foreigners)

;; define "enum event" and "struct plan"
#>
#define EV_X 111
#define EV_Y 222
<#

(define-foreign-enum-type
 (event unsigned-integer32)
 (event->int int->event)
 ((evx event/x) EV_X)
 ((evy event/y) EV_Y))

(define-foreign-record-type
 plan
 (integer nxt plan-nxt)
 (c-string msg plan-msg))

;; assume this function comes from a library, it doesn't know about event
;; or plan:
(define (print-type-info type)
 (cond ((??) (printf "~a is enum~n" type))
       ((??) (printf "~a is struct~n" type))
       (else (printf "~a is something else~n" type))))

;; And I'd hope to use it like this
(print-type-info 'plan)
(print-type-info 'event)

;; Or like this if print-type-info would need to be defined with syntax-rules.
(print-type-info plan)
(print-type-info event)
```

Any suggestions?

Thanks in advance.

Best,
-Diogo