@Override
    public int hashCode() {
        return super.hashCode() + (int)waitTime + (busyWait ? 1 : 0);
    }
Constructs an instance of this class with given argument and wait parameters.

@param arg      The argument for this function.
@param waitTime The time to wait before executing expression.
@param busyWait true if busy wait, false if not.
searchlib/src/main/java/com/yahoo/searchlib/expression/DebugWaitFunctionNode.java