Maude software language
Example of Maude specification
Maude, SRI’s high-performance declarative software language and system, is among the fastest equational rewriting systems in its class. Maude supports both equational and rewriting logic specification and programming for a wide range of applications. Important applications include metalanguage, in which the system is used to create executable environments for different logics, theorem provers, languages, and models of computation.
Maude is available to software developers at no charge.