[Haskell-cafe] How to build a generic spreadsheet?

[Neil Mitchell]

Hi

> I want to write a program where a user would update a bunch of variables,
> and everything that depends on those variables (and nothing else) are
> recalculated.  Basically, a spreadsheet, but generalized for any
> computation.  Could someone recommend an elegant way to do it or some good
> reading material?

PropLang already has the framework to do this:

http://www.cs.york.ac.uk/fp/darcs/proplang/

Take a look at the samples, you can say something like:

sb!text =< (\x -> "Word count: " ++ show (length $ words x)) =$$= txt!text

The status bar's text is the word count, and its automatically updated
if the user types.

PropLang mainly operates with Gtk, but the framework is more general.

What it does lack is much documentation :)

Thanks

Neil