public ElseClause([NotNull] FlowBuilder builder, [NotNull] ConditionNode conditionNode)
        {
            myBuilder       = builder.NotNull();
            myConditionNode = conditionNode.NotNull();

            InitialConditionNode = null;
        }
        internal ThenClause(
            [NotNull] FlowBuilder builder,
            [NotNull] string conditionDescription,
            [NotNull] Expression <Func <bool> > condition)
        {
            myBuilder = builder.NotNull();
            myConditionDescription = conditionDescription.NotNull();
            myCondition            = condition.NotNull();

            ParentConditionNode  = null;
            InitialConditionNode = null;
        }