[Rd] Eval and the enclos argument

[Duncan Murdoch]

On 02/10/2010 7:57 AM, Hadley Wickham wrote:
> Hi all,
> 
> I'm trying to understand the default value of the enclos argument of eval:
> 
>   enclos = if(is.list(envir) || is.pairlist(envir)) parent.frame()
> else baseenv()
> 
> Why isn't it just
> 
>   enclos = parent.frame()
> 
> given that enclos is only meaningful (given my reading of the
> documentation) when envir is not an environment already.
> 
> Hadley
> 


I think that handles the case of envir=NULL.

Duncan Murdoch