CHR 2014 CORR PROCEEDINGS: PAPERS WITH ABSTRACTS

ABSTRACT. We present an example for application of CHR to automated test data generation and model checking in verification of mission critical software for satellite control.

ABSTRACT. Despite its rising popularity as data format especially for web services, the software ecosystem around the JavaScript Object Notation (JSON) is not as mature as that of XML, the Extensible Markup Language. For both data formats exists schema languages to specify the structure of instance documents, but there is currently no way to translate already existing XML Schema documents into equivalent JSON Schemas.

In this paper we introduce an implementation of a language translator. It takes an XML Schema Definition (XSD) and creates its equivalent JSON Schema document. Our approach is based on Prolog and Constraint Handling Rules (CHR). By unfolding the XML Schema document into CHR constraints, it is possible to specify the concrete translation rules in a declarative way.

ABSTRACT. CHR is a declarative, concurrent and committed choice rule-based constraint programming language. We extend CHR with multiset comprehension patterns, providing the programmer with the ability to write multiset rewriting rules that can match a variable number of constraints in the store. This enables writing more readable, concise and declarative code for algorithms that coordinate large amounts of data or require aggregate operations. We call this extension CHR^cp . We give a high-level abstract semantics of CHR^cp , followed by a lower-level operational semantics. We then show the soundness of this operational semantics with respect to the abstract semantics.