When the input is present, the output is the previously received
input. When the input is absent, the output is absent. The first
time the input is present, the output is given by <i>initialValue
</i>, or if <i>initialValue </i> is not given, then the output is
absent. The output data type is greater than or equal to the input
and the <i>initialValue </i> parameter, if it is given. Note that
in contrast to the NonStrictDelay actor, this actor is strict. It
cannot fire until the input is known. While NonStrictDelay delays
by one clock tick, regardless of whether the input is present, this
actor delays only present values, and produces an output only when
the input is present.
Edward A. Lee
$Id: Pre.java 70398 2014-10-22 23:44:32Z cxh $
Ptolemy II 4.1
Yellow (eal)
Red (cxh)
Initial token value. Can be of any type.