{-# OPTIONS --cubical --guardedness #-}
module README where
-- This formalisation depends on the Cubical library, version of
-- 3 January 2026, commit a6cf6b57 and type checks with Agda 2.8.0.
-- The formalisation is structured as follows:
-- Basic lemmas/construction not available from the Cubical library
-- are included via the following file
import Prelude
-- An equivalence between fibres of pushout-products and joins of
-- fibres (Rijke 2017, Theorem 2.2) is found here
import PushoutProdFib
-- There are three directories:
-- * Categories
-- This directory contains basic constructions from (wild) category
-- theory. In particular 'proto'-wild categories are set up in:
import Categories.ProtoWildCat
-- The categories 𝑴𝑨𝑷 and 𝑭𝑨𝑴 – two takes on the arrow category over
-- the universe of types – are introduced.
import Categories.Fam
import Categories.Map
-- These are proved equivalent in the following file.
import Categories.FamMapEquiv
-- * LeibnizConstruction This directory contains the main result:
-- pushout-products are left adjoint to
-- pullback-exponentials. First, pushout-products and
-- pullback-exponentials are defined of the 𝑭𝑨𝑴 category.
import LeibnizConstruction.Fam
-- Their adjointness is then proved for this definition.
import LeibnizConstruction.Adjunction
-- Finally, the main result is proved: pushout-products and
-- pullback-exponentials are defined on 𝑴𝑨𝑷 and proved to satisfy
-- the adjunction. This is done by transporting the results over
-- from 𝑭𝑨𝑴.
import LeibnizConstruction.Map
-- The directory also contains a file where the concept of
-- orthogonal maps is defined (in terms of pushout products). Some
-- closure properties are also proved ─ in particular, closure
-- under retracts.
import LeibnizConstruction.Orthogonality
-- * STT This directory contains the application of the above results
-- in simplicial type theory. It contains one file containing, in
-- particular, the result that horn inclusions are inner anodyne.
import STT.Interval