Joachim Breitner

arbtt: Now with Documentation

Published 2009-10-11 in sections English, Haskell.

Yesterday I did what Free Software authors supposedly don’t do. I wrote documentation. In fact, I had a relatively detailed README already, but I thought this would be a good opportunity to create a more elaborate documentation, using the ubiquitous DocBook. You can read the HTML documentation for arbtt online, where it’s automatically updated when I push to the darcs repository. You can see, I use the same CSS file that most Haskell-related DocBook documentation seems to use.

One motivation to use DocBook was that I can extract manpages from it, which should be present if I package arbtt for Debian. I was about to complain that references from the manpages to other part of the documentation can not work sensibly, but using the “profiling” feature of docbook-xsl, I can replace them by a textual reference to the user’s manual if the file is processed for manpage output. Have a look at my changes for that if you want to know how it works.

For some reason, the <refentry>-tags that make up the manpages are split to separate files when generating chunked HTML output, but they do not appear in the table of contents. You have to find a spot in the text where they are linked, as they are now in the section “Program references”, to find them. This is unfortunate, I expect that a few readers might miss this important part of the documentation. Am I doing something wrong?

For the configuration file, I put an EBNF-style grammar description in the documentation. There is a special DocBook module for that, but I’m not satisfied with it. On the right hand side of production rules, it has only special support for nonterminals, but no tags to semantically mark up choice, repetition etc. I followed the lead found at the YAML specification and put <quote>-Tags around literal parts of the grammar, but this is not valid according to the DocBook DTD. Speaking of the DTD: I guess since the EBNF-stuff is just a module, the tag <productionset> is not a valid content of <figure>. So, if I choose to use the EBNF module in a sensible way, I will not have a valid DocBook file.

All in all, I am satisified with the result. Especially that nobody can say any more “I like your program, but I can’t contribute, because I don’t know Haskell”. Just improve the docs! :-)


Have something to say? You can post a comment by sending an e-Mail to me at <>, and I will include it here.