Date: Thu, 25 Sep 1997 22:25:12 +0000 (GMT) From: Terry Lambert <tlambert@primenet.com> To: bde@zeta.org.au (Bruce Evans) Cc: bde@zeta.org.au, tlambert@primenet.com, current@FreeBSD.ORG, gibbs@plutotech.com, julian@whistle.com, nate@mt.sri.com Subject: Re: new timeout routines Message-ID: <199709252225.PAA04200@usr04.primenet.com> In-Reply-To: <199709251144.VAA13138@godzilla.zeta.org.au> from "Bruce Evans" at Sep 25, 97 09:44:49 pm
next in thread | previous in thread | raw e-mail | index | archive | help
> >> Now it is (almost) idempotent (N = 1 in the above), provided the
>
> This is correct. Idempotence (for an element x in a set with a binary
> operation '*') is x*x = x.
>
> >Actually, this is "called reflexively".
>
> Wrong. Reflexivity (for an element x in a set with a binary relation
> R to itself) is xRx.
Heh. You omitted the provision stated in "provided the ...".
The "called reflexively" referred to a one-to-one relationship between
enqueing and dequeueing (or expiration) of timers. If you call untimeout
more times than you call tiemout, then it's not "called reflexively".
> > Date: 1870
> > : relating to or being a mathematical quantity which when applied to
> > itself under a given binary operation (as multiplication) equals
> > itself; also : relating to or being an operation under which a
> > mathematical quantity is idempotent
> > - idempotent noun
>
> This is correct :-). There must be a binary operation (i.e., a mapping
> SxS -> S), not just a self-relation (i.e., a mapping SxS -> {0, 1}) to
> define idempotence.
Right. Yielding the identity set is not sufficient (ulnless what you
are testing for idempotence is the identity set. 8-)). Give them a
break, it was 1870. ;-).
Terry Lambert
terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199709252225.PAA04200>