The Capabilities package
The capabilities library is an effort to make effects in Haskell more explicit by breaking the monolithic IO monad into smaller composable parts called capabilities: a use case might be an action that needs logging with current time but which should not be allowed any other IO. This exists as a pleasant middle ground between pure functions, the ST monad and the kitchen-sink IO providing a more fine-grained approach to effectful computations. Another benefit to this approach is security where a computation should only have access to resources requires to complete its job (principle of least privilege).
The implementation of the idea is based on Wouter Swierstra's Functional Pearl Data types a la carte (Journal of Functional Programming, 18(4):423-436, 2008, http://dx.doi.org/10.1017/S0956796808006758) and uses the compdata package for compositional data types.
|Dependencies||base (==4.5.*), compdata (==0.6.*), directory (==1.1.*), free (==3.4.*), unix (==2.5.*) [details]|
|Author||Baldur Blöndal, Daniel Schoepe|
|Source repository||head: git clone git://github.com/IcelandJack/Capabilties.git|
|Uploaded||Thu Aug 8 09:31:24 UTC 2013 by BaldurBlondal|
|Downloads||404 total (5 in the last 30 days)|
|Status||Docs not available [build log]
All reported builds failed as of 2015-12-05 [all 4 reports]
For package maintainers and hackage trustees