Unifying Set-Based, Delta-Based and Edit-Based Lenses

Michael Johnson, Robert D. Rosebrugh
2016 European Joint Conferences on Theory And Practice of Software  
There are many different types of lenses, but largely they fall into the three classes of the title: set-based, delta-based and edit-based lenses. This paper develops some of the general relationships between those classes. The main results are that a category of set-based lenses is a full subcategory of a category of delta-based lenses determined by sending sets to codiscrete categories; that symmetric set-based lenses can similarly be seen as symmetric delta-based lenses; that symmetric
more » ... sed lenses are able to be represented as symmetric delta-based lenses, although not as a subcategory; and that symmetric edit-based lenses can also be seen as spans of a new notion of asymmetric edit-based lenses. The importance of the paper is that it provides a substantial unification with concrete inter-conversions developed among the three main approaches to lenses in both their symmetric and asymmetric forms.
dblp:conf/etaps/JohnsonR16 fatcat:5rg3fj45zzd5plqzy2h4uurwna