while trying to write a minimal example for a problem that is bothering me, I discoverd that dput() does not work on data.tables. More precisely, the output of dput cannot be read in, most probably because the ".internal.selfref = <pointer: ..." syntax causes problems:
Hi. You can include the <pointer:...> part when posting, we know what is
meant and can fix it up if we need to. It's an R thing, from ?deparseOpts
Some exotic objects such as environments, external pointers, etc. can not
be deparsed properly. This option causes a warning to be issued if the
deparser recognizes one of these situations.
Using control = "all" comes closest to making deparse() an inverse of
parse(). However, not all objects are deparse-able even with this option.
A warning will be issued if the function recognizes that it is being asked
to do the impossible.