[Haskell-cafe] analyzing modules import/export

[Don Stewart]

j.m.m.joosten:
> 
> I am currently involved with a Haskell project to create a toolset for a
> formal language. The toolset contains a parser, a typechecker and s range of
> other features. 
>
> The Haskell code currently consists of about 20 modules. I am new in
> the project, and my impression is that a lot of code does not reside
> in the proper module. I would like to be able to get a good feeling in
> how the modules are structured, and how they are consumed by other
> modules. This would enable me to clean up a little bit. 
>
> I use eclipsefp. Do you know of any way to get insight of the
> structure of modules? is any tooling available?  Any suggestions would
> help a lot! Thanx for reading. 

There's been a few projects at Galois for this kind of high level
structural analysis. We're trying to polish them up into a release. 

For now, there's one tool you can get started with: graphmod.

This tool was written by Andy Gill (the dotgen part) and Iavor Diatchki
(the graphmod part),  and you can use it like so:

    $ git clone http://code.haskell.org/graphmod.git
    $ cd graphmod

    -- build dotgen
    $ cd dotgen
    .. edit the .cabal file to add the line:
            Build-type:          Simple
       after the Exposed-modules line
    $ cabal install

    -- build graphmod
    $ cd ..
    $ cabal install
    ...
    Installing: /home/dons/.cabal/bin

Now you have 'graphmod' a tool for drawing the module structure. 
So go find a project, and analyze it:

    $ cd ~/xmonad

    -- generate module graph
    $ graphmod XMonad XMonad.hs Main.hs > /tmp/xmonad.dot

    -- generate svg of graph
    $ dot -Tsvg /tmp/xmonad.dot > xmonad.svg

Which gives this result:

    http://galois.com/~dons/images/xmonad.svg

Enjoy!

-- Don