Abstract
Although the use of expansionary η-rewrite has become increasingly common in recent years, one area where ν-contractions have until now remained the only possibility is in the more powerful type theories of the λ-cube. This paper rectifies this situation by applying η-expansions to the Calculus of Constructions — we discuss some of the difficulties posed by the presence of dependent types, prove that every term rewrites to a unique long βη-normal form and deduce the decidability of βη-equality, typeability and type inhabitation as corollaries.
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© 1997 Springer-Verlag Berlin Heidelberg
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Ghani, N. (1997). Eta-expansions in dependent type theory — The calculus of constructions. In: de Groote, P., Roger Hindley, J. (eds) Typed Lambda Calculi and Applications. TLCA 1997. Lecture Notes in Computer Science, vol 1210. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-62688-3_35
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DOI: https://doi.org/10.1007/3-540-62688-3_35
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