Hello.

I wonder how does the type system (without -rectypes)
check cyclic type abbreviations.
The type system with -rectypes can tell between

 type 'a t = A of 'a
 type s = s t

and

 type 'a t = 'a
 type s = s t

It admit the former, but the latter.

But, the type system without -rectypes cannot tell them.
Why?
I thought that the former would be legal without -rectypes.


Regards,
Keiko NAKATA.