c2d4u3.5 packages not working in R 3.5 anymore

| Travis users are reporting a lot of these errors when testing packages on R 3.5:
| 
|   Error: package or namespace load failed for ?....? in rbind(info,
| getNamespaceInfo(env, "S3methods")):
| 
| This problem seems to happen when a c2d4u package was compiled with R
| 3.6 and is loaded in R 3.5. The problem does not appear when using the
| same r-cran-xyz package on R 3.6. I'm not entirely sure what the root
| cause is but I think it has to do with a new feature in R 3.6 (from
| the NEWS file):
| 
|   S3method() directives in ?NAMESPACE? can now also be used to perform
| delayed S3 method registration.
| 
| Maybe c2d4u3.5 packages should be compiled with R 3.5 instead of R
| 3.6? I think backward compatibility not a problem.

'3.5' is an API label.

So users should just upgrade. There is no reason to stick with R 3.5.*.

Not speaking for Michael, but I don't think aims to supply over 4,000
packages for multiple Ubuntu release _and_ multiple R versions.   In short,
when you opt into the PPAs, you also opt into the corresponding _current_ R
release.

Dirk

http://dirk.eddelbuettel.com | @eddelbuettel | edd at debian.org