[R] Canonical method for S engine selection?

[Duncan Murdoch]

On 12/6/2006 5:02 PM, Paul Roebuck wrote:
> Assuming script 'common.q' contains code that needed
> different processing depending on interpreter
> (either S-PLUS or R), what should the condition be?
> 
> if (<condition>) {
>     # Do S-PLUS code
> } else {
>     # Do R code
> }
> 
> Looking for something akin to the C preprocessor directive
> USING_R, but for S.

See ?is.R.  This function is defined in both R and current versions of 
S-PLUS; there are instructions for how to put together a test that works 
in older S-PLUS versions too.

Duncan Murdoch