We show how to systematically derive an efficient regular expression (regex) matcher using a variety of program transformation techniques, but very little specialized formal language and automata theory. Starting from the standard specification of the set-theoretic semantics of regular expressions, we proceed via a continuation-based backtracking matcher, to a classical, table-driven state machine. All steps of the development are supported by self-contained (and machine-verified) equational correctness proofs.

中文翻译：

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证明导向的程序转换：有效正则表达式匹配的功能说明

我们展示了如何使用各种程序转换技术系统地推导出一个有效的正则表达式 (regex) 匹配器，但很少有专门的形式语言和自动机理论。从正则表达式的集合论语义的标准规范开始，我们通过一个基于延续的回溯匹配器，进入一个经典的、表驱动的状态机。开发的所有步骤都由自包含（和机器验证）的等式正确性证明支持。