Proving the Genericity Lemma by Leftmost Reduction is Simple
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چکیده
Abst rac t . The Genericity Lemma is one of the most important motivations to take in the untyped lambda calculus the notion of solvability as a formal representation of the informal notion of undefinedness. We generalise solvability towards typed lambda calculi, and we call this generalisation: usability. We then prove the Genericity Lemma for un-usable terms. The technique of the proof is based on leltmost reduction, which strongly simplifies the standard proof.
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تاریخ انتشار 1995