Atomics: If of length 0 or 1, they are basically printed as they are.
Numerics are formated with num.format
.
If of length greater than 1, they are collapsed witd “,” and clipped.
so they do not become excessively long.
Expressions will be converted to plain text.
All others: Currently, only their class is simply printed
like “<data.frame>”.
Lists: The mechanism above is applied (non-recursively) to their elements.
The result looks like this:
“a=1, <unamed>=2, b=<data.frame>, c=<list>”.