[Rd] Fwd: Using existing envars in Renviron on friendly Windows

[Ivan Krylov]

Sorry for the noise! I wasn't supposed to send my previous message.

On Fri, 15 Oct 2021 16:44:28 +0200
Michał Bojanowski <michal2992 using gmail.com> wrote:

> AVAR=${APPDATA}/foo/bar
> 
> Which is a documented way of referring to existing environment
> variables. Now, with that in R I'm getting:
> 
> Sys.getenv("APPDATA")    # That works OK
> [1] "C:\\Users\\mbojanowski\\AppData\\Roaming"
> 
> so OK, but:
> 
> Sys.getenv("AVAR")
> [1] "C:UsersmbojanowskiAppDataRoaming/foo/bar"

Hmm, a function called by readRenviron does seem to remove backslashes,
but not if they are encountered inside quotes:

https://github.com/r-devel/r-svn/blob/3f8b75857fb1397f9f3ceab6c75554e1a5386adc/src/main/Renviron.c#L149

Would AVAR="${APPDATA}"/foo/bar work?

-- 
Best regards,
Ivan