handle
object to see if it is valid within the current S-PLUS
session.
handle.valid(x)
handle
object.
TRUE
if the specified
handle
object is valid within the
current S-PLUS session. Returns
FALSE
otherwise.
A
handle
object is only valid within the same S-PLUS session that
created it. The number used for the handle value is allocated in such a
way as to make it highly unlikely to be useable in a different session.
As of the time of this writing, the first handle allocated in a session
will get the number corresponding to the current time (generally the
number of seconds since January 1, 1970) when it was allocated. Each
successive handle number will be one greater than the previous one. Do
not rely on this behavior as it is considered an internal implementation
detail that may be subject to change.
Also, the
handle.valid
function is a generic method that will have
specific methods for each class that can be subclassed from the
handle
class. This gives the subclass implementors the opportunity to perform
additional validity checks based on information stored with the handle.