[R] packagename:::functionname vs. importFrom

[Peter Langfelder]

Well, I'm pretty sure that, inside package A, calling B::functionName
will not work if B has not been imported. That's why I use ::: (after
spending some time trying to figure out why :: didn't work). At least
that was the state of affairs as of R 2.9 or so, perhaps things have
changed since then.

Peter

On Mon, Jan 3, 2011 at 4:48 PM, Hadley Wickham <hadley at rice.edu> wrote:
>>> I think you mean packagename::functionname?  The three colon form is
>>> for accessing non-exported objects.
>>
>> Normally two colons suffice, but within a package you need three to
>> access exported but un-imported objects :)
>
> Are you sure?
>
>     Note that it is typically a design mistake to use ‘:::’ in your
>     code since the corresponding object has probably been kept
>     internal for a good reason.  Consider contacting the package
>     maintainer if you feel the need to access the object for anything
>     but mere inspection.
>
> Hadley
>
> --
> Assistant Professor / Dobelman Family Junior Chair
> Department of Statistics / Rice University
> http://had.co.nz/
>