Event-Driven FRP

  • Zhanyong Wan
  • Walid Taha
  • Paul Hudak
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2257)


Functional Reactive Programming (FRP) is a high-level declarative language for programming reactive systems. Previous work on FRP has demonstrated its utility in a wide range of application domains, including animation, graphical user interfaces, and robotics. FRP has an elegant continuous-time denotational semantics. However, it guarantees no bounds on execution time or space, thus making it unsuitable for many embedded real-time applications. To alleviate this problem, we recently developed Real-Time FRP (RT-FRP), whose operational semantics permits us to formally guarantee bounds on both execution time and space.

In this paper we present a formally verifiable compilation strategy from a new language based on RT-FRP into imperative code. The new language, called Event-Driven FRP (E-FRP), is more tuned to the paradigm of having multiple external events. While it is smaller than RT-FRP, it features a key construct that allows us to compile the language into efficient code. We have used this language and its compiler to generate code for a small robot controller that runs on a PIC16C66 micro-controller. Because the formal specification of compilation was crafted more for clarity and for technical convenience, we describe an implementation that produces more efficient code.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Zhanyong Wan
    • 1
  • Walid Taha
    • 1
  • Paul Hudak
    • 1
  1. 1.Department of Computer ScienceYale UniversityNew HavenUSA

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