Display instances

[o1lo01ol1o]

Raised this in gutter yesterday and am adding some notes here.

My basic thought was that it would be great to be able to define Display instances for types in the same way as one defines Show instances. Depending on how the architecture of HaskellDO evolves, I saw this effectively as compiling the instance to a JavaScript function (ghcjs) and embedding the js in the frontend. Some instances would probably need to take some form of state to update the rendered html/svg so that subsequent calls don't recompile the js on refresh.

Additionally, one could also define interfaces that would paramterize types like the mat lab functionality of creating inline sliders etc.

[NickSeagull]

Now Haskell.do allows rendering HTML/JS without any special stuff just putStrLn "String that contains HTML and JS" and it's done