[Rd] checking existence of active bindings

Martin Elff elff at sowi.uni-mannheim.de
Sun Apr 1 15:32:10 CEST 2007

On Wednesday 28 March 2007 23:56, Tony Plate wrote:
> Is there any way to check whether an active binding exists without
> actually calling the active binding?  I'd like to be able to do
> something like exists("x", ...) and know whether "x" exists without
> actually fetching its value if it is an active binding (because it could
> consume significant resources to fetch the value).
>  > exists("x", inherits=FALSE)
> getting x1
> [1] TRUE

As you most probably found out for yourself - this works
as intended.
> "x" %in% ls(globalenv())
[1] TRUE



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