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Iteratively Composing Statically Verified Traits

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 نشر من قبل EPTCS
 تاريخ النشر 2019
  مجال البحث الهندسة المعلوماتية
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Static verification relying on an automated theorem prover can be very slow and brittle: since static verification is undecidable, correct code may not pass a particular static verifier. In this work we use metaprogramming to generate code that is correct by construction. A theorem prover is used only to verify initial traits: units of code that can be used to compose bigger programs. In our work, meta-programming is done by trait composition, which starting from correct code, is guaranteed to produce correct code. We do this by extending conventional traits with pre- and post-conditions for the methods; we also extend the traditional trait composition (+) operator to check the compatibility of contracts. In this way, there is no need to re-verify the produced code. We show how our approach can be applied to the standard power function example, where metaprogramming generates optimised, and correc



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