For LABELS, a vector of Robjects (if the object is
not a vector, it is converted using as.list).
For LABEL, an Robject.
max_width
Integer vector (recycled as needed) specifying the
maximum label width for each component of x.
If NULL, there is no limit, otherwise, the label will be
truncated to max_width.
dots
A character string appended to a truncated label.
If NULL, nothing is appended.
unique
Logical indicating whether
make.unique should be called on the final
result.
Value
A character vector of labels generated from the supplied object(s).
LABELS first checks whether the object has names and uses these
if any; otherwise, LABEL is called for each element to generate
a short representation.
LABEL is generic to allow user extensions.
The current methods return the result of format if the
argument is of length 1 (for objects of classes set and
tuple: of length 5), and create a simple class
information otherwise.