use documented R API function for extptr addr

[kevinushey]

Closes #1097.

"In theory" this PR should be safe ... but I'd definitely understand if we still don't want to take it so close to release.

Checklist

• Code compiles correctly
• R CMD check still passes all tests
• Prefereably, new tests were added which fail without the change
• Document the changes by file in ChangeLog

[codecov-commenter]

Codecov Report

Merging #1098 into master will increase coverage by 20.25%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           master    #1098       +/-   ##
===========================================
+ Coverage   75.35%   95.61%   +20.25%     
===========================================
  Files          64       64               
  Lines        2784     2784               
===========================================
+ Hits         2098     2662      +564     
+ Misses        686      122      -564     

Impacted Files	Coverage Δ
src/api.cpp	100.00% <ø> (ø)
src/module.cpp	100.00% <ø> (ø)
R/Module.R	98.51% <0.00%> (+0.99%)	⬆️
inst/include/Rcpp/vector/proxy.h	94.11% <0.00%> (+11.76%)	⬆️
inst/include/Rcpp/internal/Proxy_Iterator.h	100.00% <0.00%> (+15.38%)	⬆️
inst/include/Rcpp/vector/string_proxy.h	100.00% <0.00%> (+20.00%)	⬆️
R/Attributes.R	99.66% <0.00%> (+22.97%)	⬆️
src/attributes.cpp	100.00% <0.00%> (+25.57%)	⬆️
R/RcppClass.R	73.75% <0.00%> (+73.75%)	⬆️
R/Rcpp.package.skeleton.R	82.85% <0.00%> (+82.85%)	⬆️
... and 1 more

[eddelbuettel]

Thanks, on balance I think this will have to wait til after 1.5.0 is out.

[eddelbuettel]

I rebased this against master which has the 1.0.5 release now on CRAN, and will add a new minor release version 1.0.5.1 for it.

Ok with you I hope? ;-)

[kevinushey]

LGTM -- thanks!

[eddelbuettel]

I was a little slow preparing a new rev.dep check for this 1.0.5.1 rc, but it is running. I may give a few hours, or maybe even wait til tomorrow, to see all is ok as expected and then merge.

[eddelbuettel]

It's over 1/3 done and looking reasonable so far, so merging this now.

[eddelbuettel]

Just for completeness: no issue came up, the reverse depends check concluded just fine, and I just commited the summary to the usual rcpp-logs repo.