inappropriate warning in latticeExtra

The warning message in the last line of this email is incorrect.
This is behavior which Duncan Murdoch labeled a bug in
   https://stat.ethz.ch/pipermail/r-help/2017-December/450494.html

This is a fresh install of R-devel (2018-03-21 r74436)




R Under development (unstable) (2018-03-21 r74436) -- "Unsuffered Consequences"
Copyright (C) 2018 The R Foundation for Statistical Computing
Platform: x86_64-w64-mingw32/x64 (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

  Natural language support but running in an English locale

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

library(latticeExtra)

Error in library(latticeExtra) :
  there is no package called ?latticeExtra?

install.packages("latticeExtra")

Warning in install.packages("latticeExtra") :
  'lib = "C:/Program Files/R/R-devel/library"' is not writable
--- Please select a CRAN mirror for use in this session ---
also installing the dependency ?RColorBrewer?

Warning: unable to access index for repository
http://www.stats.ox.ac.uk/pub/RWin/bin/windows/contrib/3.5:
  cannot open URL
'http://www.stats.ox.ac.uk/pub/RWin/bin/windows/contrib/3.5/PACKAGES'
trying URL 'https://cran.wu.ac.at/bin/windows/contrib/3.5/RColorBrewer_1.1-2.zip'
Content type 'application/zip' length 55444 bytes (54 KB)
downloaded 54 KB

trying URL 'https://cran.wu.ac.at/bin/windows/contrib/3.5/latticeExtra_0.6-28.zip'
Content type 'application/zip' length 2191524 bytes (2.1 MB)
downloaded 2.1 MB

package ?RColorBrewer? successfully unpacked and MD5 sums checked
package ?latticeExtra? successfully unpacked and MD5 sums checked

The downloaded binary packages are in
        C:\Users\rmh.DESKTOP-60G4CCO\AppData\Local\Temp\RtmpqA7Rqg\downloaded_packages

library(latticeExtra)

Loading required package: lattice
Loading required package: RColorBrewer

a <- xyplot(1 ~ 1)
c(a,a)

Warning message:
In formals(fun) : argument is not a function