[R6RS] `eqv?' on immutable records

R. Kent Dybvig dyb at cs.indiana.edu
Tue May 15 15:24:10 EDT 2007

> What you are advocating is a semantics that adds new
> side conditions to the beta rule, which reduces the
> number of transformations that are legal, and also
> makes the legal ones more difficult to justify.

Yes I am and have said as much.  I happen to believe it isn't a big deal
and the benefits outweigh the cost, especially given that it's not the
only or even the major inhibitor of the rule and that one can easily work
around it.

Based on the notes I've seen from Will, Mike, and Anton, however, the
concensus appears to be against me.  Since time is short, if no support
for my "all compound objects have location tags" position materializes in
the next 24 hours or so, I suggest we move ahead with the "all mutable
compound objects have location tags, but immutable compound objects may or
may not have location tags" position.


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