[plt-scheme] Please help test version 359.100

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Mon Nov 13 18:23:34 EST 2006


On Nov 13, 2006, at 5:55 PM, Matthew Flatt wrote:

> At Mon, 13 Nov 2006 08:23:29 -0500, Sam Tobin-Hochstadt wrote:
>> On Mon, 2006-11-13 at 12:26 +0800, Matthew Flatt wrote:
>>> At Mon, 6 Nov 2006 10:38:53 -0600, Robby Findler wrote:
>>>> The function for-each used to always return void. Now, it  
>>>> returns the
>>>> result of calling its functional argument on the last element of  
>>>> the
>>>> list.
>>>> [...]
>>>> I believe this change is going to be a part of r6.
>>>
>>> After further consideration, we've concluded that this change is
>>> pre-mature for PLT Scheme v360. After all, R6RS is far from  
>>> finalized,
>>> and changing `for-each' now is inconsistent with R5RS (I think).  
>>> It's
>>> good to know how much code would break with the change, but it's  
>>> better
>>> to not have to worry about it.
>>
>> I don't have an opinion about the merits of this change, but R5RS
>> explicitly leaves the return value of unspecified (6.4).
>
> But I think (I'm not sure) "unspecified" is defined to mean a single
> value.


That's far from clear. I can easily put my Editor hat on and argue that
"unspecified" means that I can return whatever bits are currently lying
around in register 137. But you are now one of those, eh, editors. So
what does your hat say?

-- Matthias, non-editor :-) 





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