Code Generation for Higher Inductive Types: A Study in Agda Metaprogramming

Abstract

Higher inductive types are inductive types that include nontrivial higher-dimensional structure, represented as identifications that are not reflexivity. While work proceeds on type theories with a computational interpretation of univalence and higher inductive types, it is convenient to encode these structures in more traditional type theories with mature implementations. However, these encodings involve a great deal of error-prone additional syntax. We present a library that uses Agda’s metaprogramming facilities to automate this process, allowing higher inductive types to be specified with minimal additional syntax.