[r6rs-discuss] [Formal] Requirement to detect circular lists

[AndrevanTonder]

On Mon, 2 Oct 2006, Dan Muresan wrote:

>> 1.  The claim of "adverse global effects on performance"
>> needs to be supported.  Having used and implemented these
>
> I agree that there don't seem to be many instances where this makes a huge
> difference. Certainly nothing becomes O(n) instead of O(1). For (length),
> for example, there's just an extra check at each step -- no need for
> hare-and-tortoise.

Could you elaborate on this last sentence (I don't see it)?

Andre