Skip to main content

Research Repository

Advanced Search

All Outputs (3)

Normalisation by evaluation for type theory, in type theory (2017)
Journal Article
Altenkirch, T., & Kaposi, A. (2017). Normalisation by evaluation for type theory, in type theory. Logical Methods in Computer Science, 13(4), https://doi.org/10.23638/LMCS-13%284%3A1%292017

© Altenkirch and Kaposi. We develop normalisation by evaluation (NBE) for dependent types based on presheaf categories. Our construction is formulated in the metalanguage of type theory using quotient inductive types. We use a typed presentation henc... Read More about Normalisation by evaluation for type theory, in type theory.

Notions of anonymous existence in Martin-Löf type theory (2017)
Journal Article
Kraus, N., Escardo, M., Coquand, T., & Altenkirch, T. (in press). Notions of anonymous existence in Martin-Löf type theory. Logical Methods in Computer Science, 13(1),

As the groupoid model of Hofmann and Streicher proves, identity proofs in intensional Martin-L\"of type theory cannot generally be shown to be unique. Inspired by a theorem by Hedberg, we give some simple characterizations of types that do have uniqu... Read More about Notions of anonymous existence in Martin-Löf type theory.

Partiality, Revisited: The Partiality Monad as a Quotient Inductive-Inductive Type (2017)
Conference Proceeding
Altenkirch, T., Danielson, N. A., & Kraus, N. (2017). Partiality, Revisited: The Partiality Monad as a Quotient Inductive-Inductive Type. In Foundations of Software Science and Computation Structures: FoSSaCS 2017 (534-549). https://doi.org/10.1007/978-3-662-54458-7_31

Capretta's delay monad can be used to model partial computations, but it has the ``wrong'' notion of built-in equality, strong bisimilarity. An alternative is to quotient the delay monad by the ``right''notion of equality, weak bisimilarity. However,... Read More about Partiality, Revisited: The Partiality Monad as a Quotient Inductive-Inductive Type.