[R] syntactical meaning of fullstop in R functions

Rolf Turner rolf.turner at xtra.co.nz
Sat Jul 13 01:47:19 CEST 2013


On 13/07/13 08:57, Kay Cichini wrote:
> just found it myself:
>
> in '.GADM' the leading period designates an internal function - the source
> can be viewed with:
> getAnywhere('.GADM')

I think that's a bit misleading.  In general, the names of functions (or 
other objects) which
are "internal" to a package need *not* begin with a full stop.  That is 
just a convention that
the author of the "dismo" package is using.  What makes an object 
"internal" really is
not being exported in the NAMESPACE of the package.

The general impact of beginning the name of an object with a full stop 
is to make that
object "invisible" to ls().  I.e. if you do an ls() of the environment 
in which that object
"lives" then you will *not* see the name of that object unless you do

     ls(.....,all.names=TRUE)

See help(ls).

     cheers,

         Rolf Turner



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