I've uploaded a new version of the pretty-show package (1.5) to Hackage, which provides some useful tools for inspecting Haskell data-structures.  I find it quite useful while debugging.

The package provides a binary and a library:  the binary, named `ppsh` can take as an input a Haskell value in standard `Show` notation, and can:

  * Either render it to a more human readable version by adding extra white-space and newlines, thus ensuring that the result is still a valid Haskell value, or

  * It can render the value as an interactive Html page, which is new in this version.

The library provides similar functionality but in a programatically.  Also, it has some support for working with non-Showable values, by using the `PrettyVal` class, which may be derived generically.

As an example, I am attaching a picture of a part of a data-structure generated with the `language-c-quote` library, by using the standard `Show` instance.

I hope you find this useful,

-Iavor