Re: [Scheme-reports] Equality of records

[Alaric Snell-Pym <alaric@x>]

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On 03/02/2012 04:49 PM, John Cowan wrote:
> Ray Dillinger scripsit:
>
>> If it requires pairs, vectors, and strings. to be recursively compared,
>> then it is not sensible to require records *not* to be recursively
>> compared.
>
> One problem is that there is no portable way to ask if two records
> have the same type, which should certainly be a requirement for equality.
>

Also, records are meant to be opaque, unless you are actually given
access to their accessors (be it lexically or dynamically, as they're
first-class procedures). Allowing them to be compared with eqv? to see
if they are the same object with respect to mutation is handy, but
allowing comparison of their internals risks violating that encapsulation...

ABS

- --
Alaric Snell-Pym
http://www.snell-pym.org.uk/alaric/
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