[datatable-help] Suggestion on ITime class implementing.

[statquant3]

I wrote almost the same message few month ago (so that Matthew knows that I
am not duplicating ids to trick him into implementing this :))

More seriously I recently discovered that R itself handles tdatetime very
wrongly. 

It has the nice POSIXlt which stores date and time as a list (on 40 bytes
which is why data.table do not handle it)
R> lt = as.POSIXlt("2011-01-01 12:32.234354")
R> attributes(lt)
$names
[1] "sec"   "min"   "hour"  "mday"  "mon"   "year"  "wday"  "yday"  "isdst"
$class
[1] "POSIXlt" "POSIXt" 

It has POSIXct which stores the datetime as a double but very often displays
the datetime wrongly

See my SO post 
http://stackoverflow.com/questions/15383057/accurately-converting-from-character-posixct-character-with-sub-millisecond-da
and the one it links to
http://stackoverflow.com/questions/7726034/how-r-formats-posixct-with-fractional-seconds

Dirk Edd. wrote something (then deleted it) stating that Windows could not
handle more than milli-second datetimes and Linux "almost" micros. I never
understood this...
He is developing a RccpBDT that expose Boost::Datetime class to R that I
would like to try but it not mature enough (according to him). 

So at the moment datetime are really a nasty thing that is not handled as
accurately as it should



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