[plt-scheme] Unnecessary use of letrec?

From: Jens Axel Søgaard (jensaxel at soegaard.net)
Date: Fri Jun 15 10:45:13 EDT 2007

Jens Axel Søgaard skrev:
> Sam TH skrev:
>> On 6/15/07, Jens Axel Søgaard <jensaxel at soegaard.net> wrote:
>>> Grant Rettke skrev:
>>> > Do most folks using mzscheme or DrS just go ahead and use the correct
>>> > form according to R5RS or instead rely on how it works in mz or DrS?
>>>
>>> Old habits die hard - so I usually follow R5RS, but since
>>> R6RS will adopt letrec* semantics for letrec, it isn't terrible
>>> important.
>>
>> This is not correct.  The current draft (and all previous drafts) of
>> R6RS have letrec* semantics for internal definitions, but the
>> semantics of letrec still have undefined evaluation order.
> 
> Thanks for the correction. I see now that letrec is kept, and a
> new letrec* is added.

Hmm. let-values and let*-values are included, but letrec-values
have been omitted. I wonder why.

-- 
Jens Axel Søgaard




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