GPCE 2018
Mon 5 - Tue 6 November 2018 Boston, Massachusetts, United States
co-located with SPLASH 2018
Mon 5 Nov 2018 14:30 - 15:00 at Studio 2 - II Chair(s): Aggelos Biboudis

In spite of the fact that many sensors in use today are binary (i.e. produce only values of 0 and 1), and that useful context-aware applications are built exclusively on top of them, there is currently no development approach specifically targeted to binary sensors. Dealing with the notions central to binary sensors, namely of state and state combinators, is tedious and error-prone in current approaches. For instance, developing such applications in a general programming language requires writing code to process events, maintain state and perform state transitions on events, manage timers and/or event histories.

In another paper, we introduced a domain specific language (DSL) called Allen, specifically targeted to binary sensors. Allen natively expresses states and state combinations, and seamlessly detects contexts on line, on incoming streams of binary events. Expressing state combinations in Allen is natural and intuitive due to a key ingredient: semi-causal operators. That paper focused on the concept of the language and its main operators, but did not address its implementation challenges. Indeed, online evaluation of expressions containing semi-causal operators is difficult, because semi-causal sub-expressions may block waiting for future events, thus generating unknown values, besides 0 and 1. These unknown values may or may not propagate to the containing expressions, depending on the current value of the other arguments.

This paper presents a compiler and runtime for the Allen language, and shows how they implement its state combining operators, based on reducing complex expressions to a core subset of operators, which are implemented natively. We define several assisted living applications both in Allen and in a general scripting language, we show that the formers are much more concise in Allen, achieve more effective code reuse, and ease the checking of some domain properties. On this basis, we believe that the Allen language may considerably simplify the development of context-aware applications over binary sensors.

Mon 5 Nov

Displayed time zone: Guadalajara, Mexico City, Monterrey change

13:30 - 15:00
IIGPCE 2018 at Studio 2
Chair(s): Aggelos Biboudis EPFL, Switzerland
13:30
30m
Talk
Exploring feature interactions without specifications: a controlled experiment
GPCE 2018
Larissa Soares Universidade Federal da Bahia, Jens Meinicke Magdeburg University, Sarah Nadi University of Alberta, Christian Kästner Carnegie Mellon University, Eduardo Santana de Almeida Universidade Federal da Bahia
14:00
30m
Talk
Inferring Ownership Domains From Refinements
GPCE 2018
Ebrahim Khalaj Wayne State University, Marwan Abi-Antoun Wayne State University
14:30
30m
Talk
Implementing a semi-causal domain-specific language for context detection over binary sensors
GPCE 2018
Nic Volanschi Inria Bordeaux, Bernard Serpette Inria, Charles Consel University of Bordeaux