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From: bakul@netcom.com (Bakul Shah)
Subject: Re: three R4RS/IEEE questions
Message-ID: <bakulD0vILL.6sD@netcom.com>
Organization: NETCOM On-line Communication Services (408 261-4700 guest)
References: <LORD.94Dec7141015@x1.cygnus.com> <3cl5rd$9u5@apple.com> <LORD.94Dec14223917@cygnus.com>
Date: Thu, 15 Dec 1994 22:32:09 GMT
Lines: 16

I am sorry but I just do not understand how a `Standard' can say
_anything_ about objects that are not specified in it.  The
`universe' of objects in the standard does not include any
nonstandard objects so phrases such as `values other than #f' can
not be construed to say anything about nonstandard objects.
Seems to to me an implementation that has, for example, a
`collection' object that acts as a vector as well as a list at
the same time (and can satisfy vector? as well as list?) can be
standard conforming *as far as the standard objects are
concerned*.  All bets are off when you extend a standard
procedure to a nonstandard object.

Now a legitimate question may be to ask what makes a `sensible'
extension.

Bakul Shah
