Re: Was not making tail recursion elmination a mistake?

From: Svein Ove Aas (svein+usenet01_at_brage.info)
Date: 06/11/04 

Date: Fri, 11 Jun 2004 21:08:33 +0200

Pascal Costanza wrote:

>
> John Thingstad wrote:
>
>> I have recently been annoyeed by the fact that tail recursion
>> elimination is
>> not part of the standard. Any ansi compliant program can now not rely
>> on recurive tail
>> elimination and must use loops or some simular structue. For mutual
>> recurion things get even uglier.
>> Wouldn't it have been better to make a commentary on the implementation
>> and require it?
>> Most implementations do anyhow.
>> What is the historic reason for this omission?
>
> There are situations in which it is better not to eliminate tail
> recursions (better debuggability, more restart options), so it would
> have been an optional feature. The ANSI standard generally doesn't cover
> optional features (or so it seems to me).
>
It seems to me that you could make it an obligatory feature that has an
option to be turned off by the programmer.

Tail-call elimination isn't exactly hard to do, is it?

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