From Semantics to Syntax: A Type Theory for Comprehension Categories

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Najmaei, Niyousha, van der Weide, Niels, Ahrens, Benedikt, North, Paige Randall
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908658223284224
author Najmaei, Niyousha
van der Weide, Niels
Ahrens, Benedikt
North, Paige Randall
author_facet Najmaei, Niyousha
van der Weide, Niels
Ahrens, Benedikt
North, Paige Randall
contents Recent models of intensional type theory have been constructed in algebraic weak factorization systems (AWFSs). AWFSs give rise to comprehension categories that feature non-trivial morphisms between types; these morphisms are not used in the standard interpretation of Martin-Löf type theory in comprehension categories. We develop a type theory that internalizes morphisms between types, reflecting this semantic feature back into syntax. Our type theory comes with $Π$-, $Σ$-, and identity types. We discuss how it can be viewed as an extension of Martin-Löf type theory with coercive subtyping, as sketched by Coraglia and Emmenegger. We furthermore define semantic structure that interprets our type theory and prove a soundness result. Finally, we exhibit many examples of the semantic structure, yielding a plethora of interpretations.
format Preprint
id arxiv_https___arxiv_org_abs_2503_10868
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle From Semantics to Syntax: A Type Theory for Comprehension Categories
Najmaei, Niyousha
van der Weide, Niels
Ahrens, Benedikt
North, Paige Randall
Programming Languages
Logic in Computer Science
Category Theory
Recent models of intensional type theory have been constructed in algebraic weak factorization systems (AWFSs). AWFSs give rise to comprehension categories that feature non-trivial morphisms between types; these morphisms are not used in the standard interpretation of Martin-Löf type theory in comprehension categories. We develop a type theory that internalizes morphisms between types, reflecting this semantic feature back into syntax. Our type theory comes with $Π$-, $Σ$-, and identity types. We discuss how it can be viewed as an extension of Martin-Löf type theory with coercive subtyping, as sketched by Coraglia and Emmenegger. We furthermore define semantic structure that interprets our type theory and prove a soundness result. Finally, we exhibit many examples of the semantic structure, yielding a plethora of interpretations.
title From Semantics to Syntax: A Type Theory for Comprehension Categories
topic Programming Languages
Logic in Computer Science
Category Theory
url https://arxiv.org/abs/2503.10868