# Applications and libraries/Extended Haskell

### From HaskellWiki

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*This page contains a list of libraries and tools in a certain category. For a comprehensive list of such pages, see Libraries and tools.*

## Extended Haskell

The purpose of these systems is to enhance the capabilities of Haskell in some way. These are not targeted at any specific application domains.

- HaRP
- A Haskell extension that extends the normal pattern matching facility with the power of regular expressions.

- Arrows
- Ross Paterson has developed a preprocessor that provides a nice notation for Arrows, a generalization of monads. This notation has been supported directly by GHC since version 6.4, so the preprocessor is only needed for other implementations.

- Functional Reactive Programming
- Functional reactive programming integrates time flow into functional programming. This provides an elegant way to express computation in domains such as interactive animations, robotics, computer vision, user interfaces, and simulation. The Yampa system is an implementation of FRP based on arrows.