[pro] (values) for for-effect functions

[Pascal Costanza]

Yes.

On 7 Dec 2010, at 19:36, Peter Seibel wrote:

> You mean PCL the CLOS implementation, right?
> 
> -Peter
> 
> On Tue, Dec 7, 2010 at 10:20 AM, Pascal Costanza <pc at p-cos.net> wrote:
>> 
>> On 3 Dec 2010, at 13:34, Martin Simmons wrote:
>> 
>>> I think it is confusing to use (values) for that purpose, because "no values"
>>> is also a valid return value (e.g. for reader macro functions
>>> http://www.lispworks.com/documentation/HyperSpec/Body/02_add.htm).
>>> 
>>> I would make it a macro, called something like void.
>>> 
>>> OTOH, use of (values) or (void) will prevent tail call optimization, so may be
>>> undesirable.
>> 
>> I think this is the strongest argument in this thread: Most other arguments seem to point out only subjective and/or stylistic issues, while this one is a hard technical difference. Preventing tail call optimizations for stylistic issues is a bad idea, IMHO.
>> 
>> I have occasionally used the (values) idiom, but only in test situations, when I don't like seeing return values in the REPL. I seem to recall some uses of (values) in PCL.
>> 
>> Pascal
>> 
>> --
>> Pascal Costanza, mailto:pc at p-cos.net, http://p-cos.net
>> Vrije Universiteit Brussel
>> Software Languages Lab
>> Pleinlaan 2, B-1050 Brussel, Belgium
>> 
>> 
>> 
>> 
>> 
>> 
>> 
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> 
> 
> 
> -- 
> Peter Seibel
> http://www.codequarterly.com/

-- 
Pascal Costanza, mailto:pc at p-cos.net, http://p-cos.net
Vrije Universiteit Brussel
Software Languages Lab
Pleinlaan 2, B-1050 Brussel, Belgium