[Rd] Conditional importFrom (roxygen?)

[Duncan Murdoch]

On 04/10/2015 10:10 AM, Jonathan Greenberg wrote:
> Folks:
> 
> I am getting a build failure when I:
> #' @importFrom utils shortPathName
> 
> which roxygenizes it to the NAMESPACE.
> 
> I suspect this is because this particular function is Windows-only, but I'm
> a bit confused how I should "properly" importFrom a function like this so
> it doesn't cause a build failure, but I don't get a note in my R CMD CHECK
> if I DON'T have it:
> 
> gdal_setInstallation : correctPath: no visible global function
>   definition for 'shortPathName'
> gdalinfo: no visible global function definition for 'glob2rx'
> gdallocationinfo: no visible global function definition for
>   'write.table'
> gdaltransform: no visible global function definition for 'write.table'
> get_subdatasets: no visible global function definition for 'glob2rx'
> mosaic_rasters: no visible global function definition for 'write.table'
> Undefined global functions or variables:
>   glob2rx shortPathName write.table
> Consider adding
>   importFrom("utils", "glob2rx", "shortPathName", "write.table")
> to your NAMESPACE.
> 
> I'll note my function actually first checks to see what OS is running, and
> doesn't use this function on non-Windows machines, so having this function
> does not cause any actual errors:
> 
> ...
> 
> if (.Platform$OS.type=="windows")
> 
> {
> 
> x <- shortPathName(x)
> 
> } else
> 
> {
> 
> x <- path.expand(x)
> 
> }
> 
> 
> ...
> 
> Is there a way to do a conditional importFrom based on the OS?  Or can I
> safely ignore this (I'm trying to submit to CRAN).
> 

Yes, you can put conditionals into the NAMESPACE file.  Apparently
roxygen2 doesn't support this feature, so you'll have to do it by hand.

Duncan Murdoch