FRP — Release of reactive-banana version 1.0

In the Haskell ecosystem, the version numbers of many libraries start with a zero. This is usually because the maintainer feels that the library is still incomplete and does not merit that magic first version number, 1.0. This is true even for some core libraries, like the bytestring library, which is currently at version 0.10.6.0.

Every now and then, however, a library author feels that his work has reached the level of completion that he originally envisioned before embarking on the unexpectedly long and perilous journey of actually building the library. Today is such a day. I am very pleased to announce the release of version 1.0 of my reactive-banana library on hackage!

As of now, reactive-banana is a mature library for functional reactive programming (FRP) that supports first-class Events and Behaviors, continuous time, dynamic event switching, push-based performance characteristics and garbage collection.

As planned, the API has changed significantly between the versions 0.9 and 1.0. The major changes are:

Dynamic event switching has become much easier to use. On the other hand, this means that all operations that depend on the previous history, like accumE or stepper are now required to be in the Moment monad.

Event s may no longer contain occurrences that are simultaneous. This is mainly a stylistic choice, but I think it makes the API simpler and makes simultaneity more explicit.

If you have been using the sodium FRP library, note that Stephen Blackheath has deprecated the Haskell variant of sodium so that he can focus on his upcoming FRP book and on the sodium ports for other languages. The APIs for sodium and reactive-banana 1.0 are very similar, porting should be straightforward.

Thanks to Markus Barenhoff and Luite Stegeman, reactive-banana 1.0 now also works with GHCJS. If it doesn’t, in particular due to premature garbage collection, please report any offending programs.

Of course, the library will continue to evolve in the future, but I think that it now has a proper foundation.

Now, go forth and program functional reactively!