Implementing a complex concept as an executable model in a strongly typed, purely functional language hits a sweet spot between mere simulation and formal specification. For research and education it is often desirable to enrich the algorithmic code with meta-logical annotations, variously embodied as assertions, theorems or test cases. Checking frameworks use the inherent logical power of the functional paradigm to approximate theorem proving by heuristic testing. Here we propose several novel idioms to enhance the practical expressivity of checking, namely meta-language marking, nominal axiomatics, and constructive existentials. All of these are formulated in literate Haskell'98 with some common language extensions. Their use and impact are illustrated by application to a realistic modeling problem.

中文翻译：

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实验性函数式编程中可检查元逻辑的实际惯用考虑

用强类型、纯函数式语言将复杂概念实现为可执行模型，在单纯的模拟和正式规范之间找到了一个最佳点。对于研究和教育，通常需要使用元逻辑注释来丰富算法代码，元逻辑注释以各种方式体现为断言、定理或测试用例。检查框架使用功能范式的内在逻辑能力来近似通过启发式测试证明的定理。在这里，我们提出了几种新颖的习语来增强检查的实际表达能力，即元语言标记、名义公理和建设性存在。所有这些都是在 Haskell'98 中用一些通用语言扩展编写的。它们的使用和影响通过对现实建模问题的应用来说明。