If you want more demonstration, I wrote a blog post[1] a while back that builds up the code to draw a maze using fgl. It only uses the basic features of the library, but I think it's a good overview of the ideas involved.

The code is up on GitHub[2] and should still work, although it might be annoying to build because the drawing code uses Cairo and Gtk.

[1]: http://jelv.is/blog/Generating-Mazes-with-Inductive-Graphs/
[2]: https://github.com/TikhonJelvis/inductive-mazes

On Wed, Jul 22, 2015 at 3:29 PM, Ivan Lazar Miljenovic <ivan.miljenovic@gmail.com> wrote:
On 23 July 2015 at 05:21, Jeffrey Brown <jeffbrown.the@gmail.com> wrote:
> Thanks, Ivan! It looks exciting. Is there a demo file floating around
> somewhere? Martin Erwig's old site [1] for FGL includes some demonstration
> code, which builds on a file called "test.hs" [2]; I know the site is
> obsolete but are those aspects of it still useful?
>
> [1] https://web.engr.oregonstate.edu/~erwig/fgl/haskell/
> [2] https://web.engr.oregonstate.edu/~erwig/fgl/haskell/test.hs

Most of those should still be valid, yes.

There's also the Examples module in fgl.

>
> On Wed, Jul 22, 2015 at 6:07 AM, Ivan Lazar Miljenovic
> <ivan.miljenovic@gmail.com> wrote:
>>
>> I'm pleased to announce that I've (finally!) just released version
>> 5.5.2.0 of [fgl].  Major changes in this release include a test suite,
>> refactorings, code clean-ups and the following potentially breaking
>> changes (in that they were previously unspecified or incorrect):
>>
>>
>>     - `nodeRange` and `nodeRangeM` for the various graph data
>>       structures erroneously returned `(0,0)` for empty graphs (making
>>       them indistinguishable from graphs containing the single node
>>       `0`).  They now match the default implementation of throwing an
>>       error.
>>
>>     - The behaviour of `delLEdge` when dealing with multiple edges was
>>       unspecified; it now deletes only a single edge and the new
>>       function `delAllLEdge` deletes all edges matching the one
>>       provided.
>>
>> All changes can be found in the changelog.
>>
>> [fgl]: https://hackage.haskell.org/package/fgl
>>
>> Along with this I'm releasing version 0.2.0.0 of [fgl-arbitrary] (i.e.
>> the "I finally build against the version on Hackage" release).
>>
>> [fgl-arbitrary]: https://hackage.haskell.org/package/fgl-arbitrary
>>
>> --
>> Ivan Lazar Miljenovic
>> Ivan.Miljenovic@gmail.com
>> http://IvanMiljenovic.wordpress.com
>> _______________________________________________
>> Haskell-Cafe mailing list
>> Haskell-Cafe@haskell.org
>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
>
>



--
Ivan Lazar Miljenovic
Ivan.Miljenovic@gmail.com
http://IvanMiljenovic.wordpress.com
_______________________________________________
Libraries mailing list
Libraries@haskell.org
http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries