Shiro Kawai wrote:

> Here's one idea:
>
> An implementation may extend make-rtd so that it can take
> a symbol 'nongenerative and another symbol (name) in the
> optional argument list.   Then make-rtd returns an RTD
> that is semantically equivalent to another RTD with the
> same field specs, parent rtd, opaqueness, sealedness,
> and the name.  How to realize this equivalence is up
> to the implementation; it can calculate a unique signature
> and use it to distinguish rtds, it can memoize make-rtd
> arguments, or it can use element-wise comparison.

Isn't that equivalent (modulo the use of 'nongenerative
instead of 'uid) to the recommended semantics for the 'uid
extension that's already described by the draft of SRFI 99?

Will