Re: Some vars now limited to fixnum size. (Was: Merging bignum to master)

[Paul Eggert]

Richard Stallman wrote:
> If n is a bignum, how many years would it take for nthcdr to return?

It'd be a tiny fraction of a year. Nanoseconds would be a better unit of 
measure. I just timed the following test case with n == 2**61 (a bignum) on a 
2-element circular list:

(setq circular (list 1 2))
(setcdr (last circular) circular)
(setq n (ash 1 61))
(nthcdr n bench-circular)

On my circa-2010 64-bit desktop with Emacs master, the nthcdr call consumes 160 
nanoseconds. (You asked "how many years": it's about 5 femtoyears. :-)