[plt-scheme] When does eqv? differ from eq? , from equal?

From: Carl Eastlund (cce at ccs.neu.edu)
Date: Mon Oct 6 13:01:02 EDT 2008

On Mon, Oct 6, 2008 at 12:28 PM, Marco Morazan <morazanm at gmail.com> wrote:
> My real question is why is there a difference for datatypes that are
> not mutable? AFAIK, for example, I can not dissect a bignum and make
> assignments to individual bigits. Would it not make more sense for eq?
> on two numbers to turn into a call to = ?
>> (= 10000000000 10000000000)
> true

The raison d'etre of eq?, as I understand it, is constant-time
operation; eqv? and = do not have this property.  Bignums can take
arbitrary time to compare.

Carl Eastlund

Posted on the users mailing list.