[Rd] attributes of environments

Thomas Lumley tlumley at u.washington.edu
Wed Jul 5 18:00:07 CEST 2006


On Tue, 4 Jul 2006, Gabor Grothendieck wrote:

> In the code below, e is an environment which we copy to f and then
> add attributes to e.  Now f winds up with the same attributes.
>
> In other words it seems that the attributes are a property of the
> environment itself and not of the variable.  Thus it appears we
> cannot have two environment variables that correspond to the
> original environment but with different attributes.

No, we can't. The two variables are references to the same environment, so 
they are the same.

If you want the attributes to be copies rather than references then create 
a list with the environment as an element and put the attributes on the 
list.

 	-thomas

Thomas Lumley			Assoc. Professor, Biostatistics
tlumley at u.washington.edu	University of Washington, Seattle



More information about the R-devel mailing list