This is a generic function for which methods can be written: only the
default method is described here. Most methods should honor the
width
argument to specify the maximum display width (as measured
by nchar(type = "width")
of the result.
The default method first converts x
to character and then
concatenates the elements separated by ", "
.
If width
is supplied and is not NULL
, the default method
returns the first width - 4
characters of the result with
....
appended, if the full result would use more than
width
characters.