Takashi Kato scripsit:

> - Can this SRFI make container like pair/vector without using pair/vector?

No, it cannot.

> - What's the reason of returning make-subtype? To me, it's not minimal.
>   You can build type system which has subtype on top of single type.
>   (c.f. sample implementation of R6RS record)

To make sure that the relationship between supertype predicates and
subtype instances holds.

> - Is this also intended to be a part of R7RS-large?

As a proposal for it, yes.

--
John Cowan          http://www.ccil.org/~cowan        xxxxxx@ccil.org
There are books that are at once excellent and boring.  Those that at
once leap to the mind are Thoreau's Walden, Emerson's Essays, George
Eliot's Adam Bede, and Landor's Dialogues.  --Somerset Maugham