AQL: A Query Language for Action Domains Modelled Using Answer Set Programming

We present a new general purpose query and abduction language for reasoning about action domains that allows the processing of simultaneous actions, definition of conditions and reasoning about fluents and actions. AQL provides a simple declarative syntax for the specification of constraints on the histories (the combination of action traces and state transitions) within the modelled domain. Its semantics, provided by the translation of AQL queries into Ans-Prolog , acquires the benefits of the reasoning power provided by Answer Set Programming (ASP). The answer sets obtained from combining the query and the domain description correspond to those histories of the domain changing over time that satisfy the query. The result is a simple, high-level query and constraint language that builds on ASP. Through the synthesis of features it offers a more flexible, versatile and intuitive approach compared to existing languages. Due to the use of ASP, AQL can also be used to reason about partial histories.