[R-pkg-devel] Native pipe in package examples

[Berwin A Turlach]

G'day Duncon,

On Thu, 25 Jan 2024 11:27:50 -0500
Duncan Murdoch <murdoch.duncan using gmail.com> wrote:

> On 25/01/2024 11:18 a.m., Henrik Bengtsson wrote:
[...]
> I think you're right that syntax errors in help page examples will be 
> installable, but I don't think there's a way to make them pass "R CMD 
> check" other than wrapping them in \dontrun{}, and I don't know a way
> to do that conditional on the R version.

I remember vaguely that 'S Programming' was discussing some nifty
tricks to deal with differences between S and R, and how to write code
that would work with either.  If memory serves correctly, those
tricks depended on whether a macro called using_S (using_R?) was
defined. Not sure if the same tricks could be used to distinguish
between different versions of R.

But you could always code your example (not tested :-) ) along lines
similar to:

if( with(version, all(as.numeric(c(major, minor)) >= c(4, 1))) ){
  ## code that uses native pipe
}else{
  cat("You have to upgrade to R >= 4.1.0 to run this example\n")
}


> I would say that a package that doesn't pass "R CMD check" without 
> errors shouldn't be trusted.

Given the number of packages on CRAN and Murphy's law (or equivalents),
I would say that there are packages that do pass "R CMD check" without
errors but shouldn't be trusted, own packages not excluded. :)

Cheers,

	Berwin