[Rd] Eval and the enclos argument
hadley at rice.edu
Sat Oct 2 16:40:33 CEST 2010
On Sat, Oct 2, 2010 at 8:18 AM, Duncan Murdoch <murdoch.duncan at gmail.com> wrote:
> 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.
> I think that handles the case of envir=NULL.
So that makes eval(expr, NULL) equivalent to eval(expr, baseenv()), right?
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
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