R devel - Oct 2012 - Class generator functions for reference classes

As of rev. 61035 in r-devel, setRefClass() now returns a generator 
function, as setClass() has done since 2.15.0.

The convenient style is now:
   mEdit <- setRefClass("mEdit",......)
   xx <- mEdit(data = xMat)

instead of
   xx <- mEdit$new(data = xMat)

The returned object still has fields and methods accessible as before.

See the "Value" and "Reference Class Generators" sections of
?ReferenceClasses for details.

Thanks to Romain Fran?ois for suggesting this.

John

A heads up for those using Rcpp and perhaps other packages related to 
reference classes.

The changes in 61035 cause a problem for classes defined with a slot 
using the return value of setRefClass(), notably for Rcpp. The name of 
that class changed.

Rather than introduce back-incompatibility, I will rename a couple of 
classes so the class name of the return value remains the same.  (It's 
not as natural a naming scheme as what is in place, but not the first 
time back-compatibility has won out over preferred design.)

It will be a day or two before I can get to this, so don't panic if your 
package does not install from the current r-devel until then.

John

On 10/27/12 2:07 PM, John Chambers wrote:
> As of rev. 61035 in r-devel, setRefClass() now returns a generator 
> function, as setClass() has done since 2.15.0.
>
> The convenient style is now:
>   mEdit <- setRefClass("mEdit",......)
>   xx <- mEdit(data = xMat)
>
> instead of
>   xx <- mEdit$new(data = xMat)
>
> The returned object still has fields and methods accessible as before.
>
> See the "Value" and "Reference Class Generators"
sections of
> ?ReferenceClasses for details.
>
> Thanks to Romain Fran?ois for suggesting this.
>
> John
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel

> As of rev. 61035 in r-devel, setRefClass() now returns a generator
function,
> as setClass() has done since 2.15.0.
>
> The convenient style is now:
>   mEdit <- setRefClass("mEdit",......)
>   xx <- mEdit(data = xMat)
>
> instead of
>   xx <- mEdit$new(data = xMat)
>
> The returned object still has fields and methods accessible as before.
Similarly, would it be possible for setGeneric and setMethod to return
the equivalent generic and method objects?

Hadley

-- 
RStudio / Rice University
http://had.co.nz/