arXiv subjects

Jan C. Dageförde

Publications and source records attributed to Jan C. Dageförde.

3 recordsLinked to original sources

arXiv2020

Constraint-Logic Object-Oriented Programming with Free Arrays

Constraint-logic object-oriented programming provides a useful symbiosis between object-oriented programming and constraint-logic search. The ability to use logic variables, constraints, non-deterministic search, and object-oriented programming in an integrated way facilitates the combination of search-related program parts and other business logic in object-oriented applications. With this work we conceptualize array-typed logic variables ("free arrays"), thus completing the set of types that logic variables can assume in constraint-logic object-oriented programming. Free arrays exhibit interesting properties, such as indeterminate lengths and non-deterministic accesses to array elements.

cs.PL↗

arXiv2019

Structured Traversal of Search Trees in Constraint-logic Object-oriented Programming

In this paper, we propose an explicit, non-strict representation of search trees in constraint-logic object-oriented programming. Our search tree representation includes both the non-deterministic and deterministic behaviour during execution of an application. Introducing such a representation facilitates the use of various search strategies. In order to demonstrate the applicability of our approach, we incorporate explicit search trees into the virtual machine of the constraint-logic object-oriented programming language Muli. We then exemplarily implement three search algorithms that traverse the search tree on-demand: depth-first search, breadth-first search, and iterative deepening depth-first search. In particular, the last two strategies allow for a complete search, which is novel in constraint-logic object-oriented programming and highlights our main contribution. Finally, we compare the implemented strategies using several benchmarks.

cs.PL↗

arXiv2019

Reference Type Logic Variables in Constraint-logic Object-oriented Programming

Constraint-logic object-oriented programming, for example using Muli, facilitates the integrated development of business software that occasionally involves finding solutions to constraint-logic problems. The availability of object-oriented features calls for the option to use objects as logic variables as well, as opposed to being limited to primitive type logic variables. The present work contributes a concept for reference type logic variables in constraint-logic object-oriented programming that takes arbitrary class hierarchies of programs written in object-oriented languages into account. The concept discusses interactions between constraint-logic object-oriented programs and reference type logic variables, particularly invocations on and access to logic variables, type operations, and equality. Furthermore, it proposes approaches as to how these interactions can be handled by a corresponding execution environment.

cs.PL↗