Or a reference type variable might not hold a reference to any object, in which case it is said to be a null reference or a reference to Nothing.

或者，引用类型变量可能不存放对任何对象的引用，这种情况称为空引用。

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This paper tentatively analyzes the realization mechanism of a reference type variable in C, and compares reference and pointer so as to deepen the comprehension of reference.

为准确理解C语言引用的本质，对C语言引用型变理的实现机制进行了初步探讨。

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The rule project can reference the CEIEventBOM module and define a variable with type ilog.connector.ibm.runtime.EventContainer to emit CEI events to Process Server.

规则项目可以引用 CEIEventBOM 模块并定义一个 ilog.connector.ibm.runtime.EventContainer 类型的变量，从而把 CEI 事件发送给 Process Server。

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