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Re: [Scheme-reports] eq? and eqv? for records

Alex Shinn <alexshinn@x> writes:

> On Fri, Feb 14, 2014 at 10:17 PM, Taylan Ulrich Bayırlı/Kammer
> <taylanbayirli@x> wrote:
> I'm not sure what you're trying to specify about the
> initial values here, but it may be simpler to just leave
> this out. "The constructor guarantees a newly allocated
> record if there are any mutable fields." You can't assume
> anything about immutable records, including the degenerate
> empty record case.

I was trying to make it explicit in some way that (immutable) records
with different values in their fields cannot be the same record, though
it's obvious.  Just trying to "not leave any holes" in the wording so to

>     Ideally, IMO, the equivalence semantics of all objects created
>     with constructors would follow the logic we used for procedures
> Ah, well this was rather controversial itself :) While
> a stronger case can be made for desiring predictable
> record identity, similar optimizations still apply. This
> isn't really something we can just write in as an errata.

Indeed, I went into a rant there about things I only figured out since
after the procedure equivalence discussion and thus couldn't bring up
elsewhere, sorry about that.


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