The elerea package
Elerea (Eventless reactivity) is a tiny discrete time FRP implementation without the notion of event-based switching and sampling, with first-class signals (time-varying values). Reactivity is provided through various higher-order constructs that also allow the user to work with arbitrary time-varying structures containing live signals. Signals have precise and simple denotational semantics.
Stateful signals can be safely generated at any time through a monadic interface, while stateless combinators can be used in a purely applicative style. Elerea signals can be defined recursively, and external input is trivial to attach. The library comes in three major variants:
Simple: signals are plain discrete streams isomorphic to functions over natural numbers;
Param: adds a globally accessible input signal for convenience;
Clocked: adds the ability to freeze whole subnetworks at will.
This is a minimal library that defines only some basic primitives, and you are advised to install elerea-examples as well to get an idea how to build non-trivial systems with it. The examples are separated in order to minimise the dependencies of the core library. The dow package contains a full game built on top of the simple variant.
The basic idea of the implementation is described in the WFLP 2010 paper Efficient and Compositional Higher-Order Streams (http://sgate.emt.bme.hu/documents/patai/publications/PataiWFLP2010.pdf).
Additional contributions: Takano Akio
|Versions||0.1.0, 0.2.0, 0.3.0, 0.4.0, 0.5.0, 0.6.0, 1.0.0, 1.1.0, 1.2.0, 1.2.1, 1.2.2, 1.2.3, 2.0.0, 2.1.0, 2.2.0, 2.3.0, 2.4.0, 2.5.0, 2.6.0, 2.7.0, 22.214.171.124, 126.96.36.199|
|Dependencies||base (4.*), containers|
|Copyright||(c) 2009-2012, Patai Gergely|
|Maintainer||Patai Gergely (email@example.com)|
|Upload date||Sun Apr 1 07:54:43 UTC 2012|