type-date-time.md
In vctrs: Vector Helpers

datetime coercions are symmetric and unchanging

Code
  print(mat)
Output
                       date                   datetime<local>        datetime<US/Central>   POSIXlt<US/Central>    duration<mins>   duration<secs>  
  date                 "date"                 "datetime<local>"      "datetime<US/Central>" "datetime<US/Central>" NA               NA              
  datetime<local>      "datetime<local>"      "datetime<local>"      "datetime<US/Central>" "datetime<US/Central>" NA               NA              
  datetime<US/Central> "datetime<US/Central>" "datetime<US/Central>" "datetime<US/Central>" "datetime<US/Central>" NA               NA              
  POSIXlt<US/Central>  "datetime<US/Central>" "datetime<US/Central>" "datetime<US/Central>" "datetime<US/Central>" NA               NA              
  duration<mins>       NA                     NA                     NA                     NA                     "duration<mins>" "duration<secs>"
  duration<secs>       NA                     NA                     NA                     NA                     "duration<secs>" "duration<secs>"