Interactive Haskell Documents

Pivotal is a document-centered presentation of Haskell. It aims to provide a user-friendly environment in which Haskell documents can be interactively developed and manipulated. A Haskell document is essentially an ordinary Haskell module that may also include free-standing Haskell expressions. When a document is displayed, the values of any such expressions are evaluated and displayed in-place.

Think of a document containing code, comments, and examples, all presented in an aesthetically pleasing manner. The document is live, so you can make changes and see them immediately. This reminds me somewhat of the Lab system in J: interactive tutorials that allow the user to experiment after each new point is presented.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

The direct manipulation

The direct manipulation stuff looks cool.

Related (?)

Recent work by Conal Elliott is interesting, and seems related, in that it also concerned the presentation of interactive, functional values.

See his paper Functional Programming by Interacting with Tangible Values; and real haskell code.

I haven't tinkered with this yet, but am looking forward to doing so.