Propagators propagate increases in information from cell to cell.
They are described (using Scheme) in Alexey Radul and Gerald Sussman's "The Art of the Propagator" as well as in Alexey Radul's thesis on Propagation Networks.
This package explores design options for propagators in Haskell. The primary innovation here (beyond the published work) is the use of observable sharing to let us take a more direct form of programming and transform it back and forth to the propagator style.
Contributions and bug reports are welcome!
Please feel free to contact me through github or on the #haskell IRC channel on irc.freenode.net.
-Edward Kmett