Abstract
There are several approaches to the problem of giving a categorical semantics to Martin-Löf type theory with dependent sums and products and extensional equality types. The most established one relies on the notion of a type-category (or category with attributes) with \({\it \Sigma}\) and \({\it \Pi}\) types. We extend such a semantics by introducing coinductive types both on the syntactic level and in a type-category. Soundness of the semantics is preserved.
As an example of such a category, we prove that the type-category built over a locally cartesian closed category \({\mathcal C}\) admits coinductive types whenever \({\mathcal C}\) has final coalgebras for all polynomial functors.
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De Marchi, F. (2005). On the Semantics of Coinductive Types in Martin-Löf Type Theory. In: Fiadeiro, J.L., Harman, N., Roggenbach, M., Rutten, J. (eds) Algebra and Coalgebra in Computer Science. CALCO 2005. Lecture Notes in Computer Science, vol 3629. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11548133_8
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DOI: https://doi.org/10.1007/11548133_8
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-28620-2
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