From ross at biostat.ucsf.edu  Thu Dec  3 22:35:02 2009
From: ross at biostat.ucsf.edu (Ross Boylan)
Date: Thu, 03 Dec 2009 13:35:02 -0800
Subject: [Rd] group generics
In-Reply-To: <4B1826EC.5090504@fhcrc.org>
References: <1259109265.8792.22.camel@markov.biostat.ucsf.edu>
	<6ph3a428z2r.fsf@gopher4.fhcrc.org> <4B144DC4.3020904@biostat.ucsf.edu>
	<4B1826EC.5090504@fhcrc.org>
Message-ID: <1259876102.9331.1.camel@markov.biostat.ucsf.edu>

Thanks for your help.  I had two concerns about using as: that it would
impose some overhead, and that it would require me to code an explicit
conversion function.  I see now that the latter is not true; I don't
know if the overhead makes much difference.

On Thu, 2009-12-03 at 13:00 -0800, Martin Morgan wrote:
> setMethod("Arith", signature(e1="numeric", e2="B"), function(e1, e2) {
>     new("B", xb=e1*e2 at xb, callGeneric(e1, as(e2, "A")))
> })

Things were getting too weird, so I punted and used explicitly named
function calls for the multiplication operation that was causing
trouble.

Ross



[Rd] group generics
Ross Boylan