Nominal Verification of Algorithm W

نویسندگان

  • Christian Urban
  • Tobias Nipkow
چکیده

The Milner-Damas typing algorithm W is one of the classic algorithms in Computer Science. In this paper we describe a formalised soundness and completeness proof for this algorithm. Our formalisation is based on names for both term and type variables, and is carried out in Isabelle/HOL using the Nominal Datatype Package. It turns out that in our formalisation we have to deal with a number of issues that are often overlooked in informal presentations of W. “Alpha-conversion always bites you when you least expect it.” A remark made by Xavier Leroy when discussing with us the informal proof about W in his PhD-thesis [7].

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تاریخ انتشار 2008