On Tue, 28 Sep 2004, Alex Shinn wrote:

> However, realistically most implementations either use a relative of
> TinyCLOS (for which slot-setting is customizable with the MOP and for
> immutable fields and left unchanged for mutable fields at no extra
> cost) or Meroon (which already supports immutable fields), so this
> isn't really an issue.

This is a little late to add to the discussion, but I just want to
contest the claim that most serious Scheme systems that provide first-
class record type descriptors base/implement their record systems atop
CLOS-style frameworks such as Tiny-CLOS or Meroon.  I can think of only
three implementations that do such a thing -- Gauche, RScheme, & STklos
--, whereas I can think of a very large number of others that either
don't support such frameworks at all or, if they do, don't base their
record systems on them (T, Scheme48, MIT Scheme, Gambit, Chicken, SISC,
Larceny, Chez, PLT, probably SCM & guile, and anything that uses SLIB
or Jonathan Rees's records proposal from the late '80s; there are also
surely a few more that elude my memory right now).  So I don't think
it's really reasonable to just punt arguments on the basis that they're
solved automatically by such CLOS-style frameworks.