[R] Call by reference: Was: Object orientation?

Thomas Lumley tlumley at u.washington.edu
Fri Mar 23 12:26:13 CET 2001


On 22 Mar 2001, Peter Dalgaard BSA wrote:

> "Henrik Bengtsson" <henrikb at braju.com> writes:
>
> > To reply to Yves Gauvreau question (Jan 24, 2001) about how to set values
> > within function, it is possible to do without without using the "<<-"
> > assignment operator or other nasty tricks. I had the same problem and I did
> > a nasty workaround two weeks ago implementing the functionality of reference
> > variables, but today I "ran into" the [R] help page for ".Alias". With
> > .Alias one can immitate call by reference! Here is an example that shows how
> > it works:
> .....
> > set <- function(object, value) {
> >   this <- .Alias(object);
> >   this$value <- value;
> >   return (invisible());
> > }
>
> It may work, but I wouldn't think it is documented to do so and could
> easily get blown away by an internal change (and *I'm* not going to put
> checks in to ensure that it keeps working)!


Some of us talked about putting
  Usage: this function should not be used
in the .Alias help page. It doesn't seem to have happened, but you get the
idea.

	-thomas

-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-help-request at stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._



More information about the R-help mailing list