arXiv subjects

Angel Herranz

Publications and source records attributed to Angel Herranz.

2 recordsLinked to original sources

arXiv2026

Logic Programming with Extensible Types

Logic programming languages present clear advantages in terms of declarativeness and conciseness. However, the ideas of logic programming have been met with resistance in other programming communities, and have not generally been adopted by other paradigms and languages. This paper proposes a novel way to incorporate logic programming in an existing codebase in a typed functional programming language. Our approach integrates with the host language without sacrificing static typing, and leverages strengths of typed functional programming such as polymorphism and higher-order. We do so by combining three ideas. First, we use the extensible types technique to allow values of the host language to contain logic variables. Second, we implement a unification algorithm that works for any data structure that supports certain operations.Third, we introduce a domain-specific language to define and query predicates. We demonstrate our proposal via a series of examples, and provide aids to make the notation convenient for users, showing that the proposed approach is not just technically possible but also practical. Our ideas have been implemented in the language Haskell with very good results.

cs.PL↗

arXiv2006

Demand Analysis with Partial Predicates

In order to alleviate the inefficiencies caused by the interaction of the logic and functional sides, integrated languages may take advantage of \emph{demand} information -- i.e. knowing in advance which computations are needed and, to which extent, in a particular context. This work studies \emph{demand analysis} -- which is closely related to \emph{backwards strictness analysis} -- in a semantic framework of \emph{partial predicates}, which in turn are constructive realizations of ideals in a domain. This will allow us to give a concise, unified presentation of demand analysis, to relate it to other analyses based on abstract interpretation or strictness logics, some hints for the implementation, and, more important, to prove the soundness of our analysis based on \emph{demand equations}. There are also some innovative results. One of them is that a set constraint-based analysis has been derived in a stepwise manner using ideas taken from the area of program transformation. The other one is the possibility of using program transformation itself to perform the analysis, specially in those domains of properties where algorithms based on constraint solving are too weak.

cs.PL↗