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Swapping: a natural bridge between named and indexed explicit substitution calculi

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 نشر من قبل EPTCS
 تاريخ النشر 2011
  مجال البحث الهندسة المعلوماتية
والبحث باللغة English
 تأليف Ariel Mendelzon




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This article is devoted to the presentation of lambda_rex, an explicit substitution calculus with de Bruijn indexes and a simple notation. By being isomorphic to lambda_ex - a recent formalism with variable names -, lambda_rex accomplishes simulation of beta-reduction (Sim), preservation of beta-strong normalization (PSN) and meta-confluence (MC), among other desirable properties. Our calculus is based on a novel presentation of lambda_dB, using a swap notion that was originally devised by de Bruijn. Besides lambda_rex, two other indexed calculi isomorphic to lambda_x and lambda_xgc are presented, demonstrating the potential of our technique when applied to the design of index



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