The aim of the paper is to provide solid foundations for a programming paradigm natively supporting the creation and manipulation of cyclic data structures. To this end, we describe coFJ, a Java-like calculus where objects can be infinite and methods are equipped with a codefinition (an alternative body). We provide an abstract semantics of the calculus based on the framework of inference systems with corules. In coFJ with this semantics, FJ recursive methods on finite objects can be extended to infinite objects as well, and behave as desired by the programmer, by specifying a codefinition. We also describe an operational semantics which can be directly implemented in a programming language, and prove the soundness of such semantics with respect to the abstract one.

中文翻译：

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coFJ 中的 Sound Regular Corecursion

本文的目的是为原生支持循环数据结构的创建和操作的编程范式提供坚实的基础。为此，我们描述了 coFJ，一种类似于 Java 的演算，其中对象可以是无限的，并且方法配备了代码定义（替代体）。我们基于带有 coules 的推理系统框架提供了微积分的抽象语义。在具有这种语义的 coFJ 中，有限对象上的 FJ 递归方法也可以扩展到无限对象，并通过指定代码定义来按照程序员的需要运行。我们还描述了一种可以直接在编程语言中实现的操作语义，并证明了这种语义相对于抽象语义的合理性。