So, I just wrote my own "cleanroom" version of srfi-136 as a laborious - but very gratifying - exercise. It's not useful as another reference as it's chock-full of non-portable internals from my system.
I borrowed the tests from the sample implementation, and added a few more as I was coding some corner cases. The following forms fail in expansion on the sample implementation. I double-checked them on chibi to make sure the failures weren't caused by some bug in my own syntax-rules:
;; middle record type has no constructor, and 2 or more fields
(let ()
(define-record-type <base> (make-base) base?)
(define-record-type (<middle> <base>) #f middle? (a middle-a middle-a-set!) (b middle-b middle-b-set!))
(define-record-type (<leaf> <middle>) (make-leaf d) leaf? (d leaf-d))
'ok)
;; type with unnamed field and no constructor
(let () (define-record-type <simple> #f simple? (#f foo set-foo!)) 'ok)
Pedantic nit:
"Furthermore, the macro use (<type name>) macro-expands into an object that serves as a runtime record-type descriptor for the procedural interface (see below)."
should be "...macro-expands into an expression that evaluates to an object that serves ..."