[R] Genuine relative paths with R

Olivier GIVAUDAN
Wed, 10 Oct 2018 23:53:41 -0000

Yes, I am aware that both '__FILE__' and 'SAS_EXECFILENAME' are
macro variables. I don't know how the VBA
'Application.ThisWorkbook.Path' VBA or PHP '__DIR__' (or
'__FILE__') work.

And yes, indeed, until now I didn't even realise that this simple
find-and-replace solution of "mine" is actually the basic job of a
preprocessor when it expands macro variables, thank you!

A macro language in R, yes, I think it would be useful, at least for this
function. If nothing simpler is available, of course...
________________________________
De : Peter Claussen <dakotajudo at mac.com>
Envoy? : mercredi 10 octobre 2018 23:29
? : Olivier GIVAUDAN
Cc : Duncan Murdoch; Jeff Newmiller; r-help at r-project.org
Objet : Re: [R] Genuine relative paths with R

If I?m following all this correctly, it seems your criticism is that R doesn?t
provide a run-time function that is equivalent to a compile-time macro. You do
realize that __FILE__ is not part of the C programming language - it?s a
predefined variable recognized by the cpp - the C preprocessor program.
Similarly, SAS_EXECFILENAME is a predefined variable that can be recognized by
the SAS macro processor, but has no meaning in the SAS language itself.

So, to go back to your original post:
1.  Either create a variable "ScriptPath" in the first lines of each
of my R scripts and run a batch (or shell, etc.) to replace every single
occurrence of "ScriptPath <-" by "ScriptPath <- [Absolute
path of the R script]" in all the R scripts located in the folder (and
possibly subfolders) of the batch file.

This is what a macro processor does. Are you asking for a macro language in R?

Cheers

On Oct 10, 2018, at 6:11 PM, Olivier GIVAUDAN <olivier_givaudan at
hotmail.com<mailto:olivier_givaudan at hotmail.com>> wrote:

It is not wrong to claim that R currently doesn't have a function returning
the path of the R file where this same function was invoked.

'getwd()' is indeed not equivalent to VBA