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Re: [Scheme-reports] multiple values module

On Mon, 23 May 2011 07:45:26 -0400, Alaric Snell-Pym  
<alaric@x> wrote:

> On 05/22/11 17:43, Peter Bex wrote:
>> This behaviour is quite practical and even enables a new idiom;
>> procedures can return one "main" value and several additional values
>> that you might sometimes need.  Then you can just call the procedure
>> as if it returned one value when you don't need the extra info.
> I like this idiom, too.

I might note, however, that his sort of idiom, is far different than the  
Chibi behavior. The abstraction of multiple values is not lost, because  
the multiple values are not reified. Chibi reifies multiple values into  
something that one cannot distinguish from a list, and that is, IMO, a bad  
thing. If reification happens, then it should be as a distinct type, and  
not as a tagged list.

I'm fine with the standard being lax on this point, and I think even the  
more "specified" R6RS left multiple values fairly open, but I do not think  
it would be a bad thing to specify a few things to keep up abstraction  
barriers. Maybe I'm missing something big here?

	Aaron W. Hsu

Programming is just another word for the lost art of thinking.

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