On Mon, Jan 4, 2016 at 7:26 AM, John Cowan <xxxxxx@mercury.ccil.org> wrote:

R7RS-small was all about compatibility.

Compatibility, but never at the expense of design.  Those
few places we thought we could make a clear improvement
we did so.  The reason there are so few of these is because
Scheme is already such a clean and simple language.

For new features we erred on the side of doing nothing
rather than adding a workaround or wart.  I think the large
language should be less conservative in new features
(how much so is debatable), but if you really want compatibility
regarding hash function APIs, just abandon salt/bounds rather
than adding ugly workarounds.