Creates a tracker that provides the difference between a set of input files for successive invocations.
Creates a tracker that provides the difference between a set of output files for successive invocations.
Creates a tracker that indicates whether the arguments given to f have changed since the most recent invocation.
Creates a tracker that provides the output of the most recent invocation of the function
Creates a tracker that provides the last time it was evaluated.
Creates a tracker that provides the last time it was evaluated. If 'useStartTime' is true, the recorded time is the start of the evaluated function. If 'useStartTime' is false, the recorded time is when the evaluated function completes. In both cases, the timestamp is not updated if the function throws an exception.