## Test environments
* Microsoft windows 10 Enterprise, R 3.6.0
* ubuntu 14.04 (on travis-ci), R 3.6.0
* win-builder (devel and release)

## R CMD check results

0 errors | 0 warnings | 0 notes

## Responding to Kurt Hornik's comments on 2020-05-19

* type.convert() is always called with an explicit "as.is" argument", to comply with new rules

