[Haskell-cafe] Visualizing function application

[Martijn van Steenbergen]

Dear café,

I am deeply impressed with Vacuum[1][2], Ubigraph[3] and especially 
their combination[4]. I can trivially and beautifully visualize the ASTs 
that my parser produces. I can visualize zippers of the ASTs and confirm 
that sharing is optimal.

Ubigraph is also able to animate graph *mutations*, as shown by the 
various demos on Ubigraph's website. How cool would it be if we could 
tell vacuum-ubigraph: here, show this tree, and then show how the tree 
changes when we apply this function on it. We could see how [1,2,3] is 
transformed into a ring when cycle is applied on it, or we could see how 
a list is consumed node by node when a foldr is applied.

I have no idea how difficult this is or how to begin, so I thought I'd 
throw the idea out here. Perhaps it is appealing enough that someone 
picks it up and implements it. :-)

Martijn.


[1] http://hackage.haskell.org/package/vacuum
[2] http://www.youtube.com/watch?v=oujaqo9GAmA
[3] http://ubietylab.net/ubigraph/content/Demos/index.html
[4] http://hackage.haskell.org/package/vacuum-ubigraph