With the development of Internet Things, millions sensors are being deployed in cities to collect real-time data. This leads a need for checking city states against requirements at runtime. In this article, we develop novel spatial-temporal specification-based monitoring system smart cities. We first describe study over 1000 requirements, some which cannot be specified using existing logic, suc...

Logic programming requires that the programmer convert a problem into a set of constraints based on predicates. Choosing the predicates and introducing appropriate constraints can be intricate and error-prone. If the problem domain is structured enough, we can let the programmer express the problem in terms of more abstract, higherlevel constraints. A compiler can then convert the higher-level ...

Conflict-free replicated data types (CRDTs) are a promising tool for designing scalable, coordination-free distributed systems. However, constructing correct CRDTs is difficult, posing challenge even seasoned developers. As result, CRDT development still largely the domain of academics, with new designs often awaiting peer review and manual proof correctness. In this paper, we present Katara, p...

Most dependently-typed p rogramming languages either require that all expressions terminate (e.g. Coq, Agda, and Epigram), or allow infinite loops but are inconsistent when viewed as logics (e.g. Haskell, ATS, Ωmega). Here, we combine these two approaches into a single dependently-typed core language. The language is composed of two fragments t hat share a common syntax and overlapping semantic...

Logic puzzles such as Sudoku are described by a set of properties that a valid solution must have. Constraints are a useful technique to describe and solve for such properties. However, constraints are less suited to express imperative interactions in a user interface for logic puzzles, a domain that is more readily expressed in the objectoriented paradigm. Object constraint programming provide...