The YARD Roadmap to 1.0

By Loren Segal on February 22nd, 2008 at 4:45 AM

It’s been almost a year now since the last release, but today I released a new version of my Ruby documentation tool, YARD 0.2.1. This release gives the tool a surprising amount of robustness for the little code I changed and should make it easier for people to play around with, since it can currently parse the following gems without exploding: merb-core, merb-more, datamapper and obviously yard. You can actually see them here, but don’t judge them for aesthetic merit— the templates were hacked together to show off the introspective power of the documentation, not the visual results. In fact, the only docs worth looking at are the yard docs, because without the Yardoc formatting, a lot of the point is lost. I believe it works with active_record too but I haven’t tried it recently. You can install YARD with a simple:

sudo gem install yard

To run this tool against your Ruby code just type in yardoc in your root directory; a doc directory will be created with an index.html file you can run to see the results, providing it didn’t crash in the process. Note: It still is horribly buggy.

For those who don’t know (and haven’t clicked the above link to YARD’s homepage), YARD is a Ruby documentation tool meant to fix all the problems with RDoc. There are plenty, and I outlined them all on the YARD site, so read up. After you read up, close that page, because it’s horribly out of date.

Where I’ve been

This gem update was a long time coming. A long time thinking, and a long time pondering over what YARD would be and where it would go. I was very disappointed with the state of the code (read: parser) when I gave up, and I also got a little sidetracked over last summer with an internship at Apple, so I kind of abandoned it knowing I would eventually come back. Between having people actually ask me about my progress, and Merb’s docs using a format very similar to the one I created, I think it’s becoming increasingly clear that the time is either now or very soon.

And so, I had a chance to look at the yard source again recently and realized it actually works a lot better than I thought it did. I applied a few patches, and here we are.

But there is still plenty of work to be done.

I’ve actually known how I wanted to get to 1.0 for a while now. This week I bumped into a colleague of mine on the same flight as me to Seattle (well, he was going to Frisco for GDC, me to Redmond for a MS interview, more on that later) and we got to chatting about a bunch of projects we’ve been working ended up discussing how we plan our milestones for projects. I actually laid out my entire roadmap to him right there, so I figure I’ll make it more official and put it out on my blog for those interested in developments.

The Roadmap

I plan on dividing my releases in ‘0.x.0 – 0.x.9’ segments to target one specific design feature all the way up to 1.0. There will be a number of iterations for each design feature, but for the most part each feature will be able to be developed independently/concurrently. That is to say, I plan on seeing through development of 0.3.x potentially before even finishing 0.2.x. As for what each exact release will be, that will depend on how development goes. I can’t get that detailed just yet.

0.2.0 – 0.2.9: Parser fixes / complete parser rewrite

The parser is horrid and needs to be fixed. On the other hand, every parser is horrid, so I’ll live with it the horridness. What I can’t live with is the bugginess. My only wish is that I define the grammar formally using some parser generator, that way I don’t have to look at the ugly part of the code. Ragel is currently my top choice, but Adrian Thurston personally recommended I look at Island parsing. There’s a lot of reading to do, and a lot of time to do it in. This code will need to change as Ruby does (going from 1.8 to 2.0) and there is a lot of testing that has to go through to get it working right. This iteration will probably take a long time. We can potentially use the Ruby lex file to do the lexing, but I don’t know much about hacking with that. Help.

0.3.0 – 0.3.9: Fixing the developer API

YARD holds itself on being an extensible / modular piece of code that could easily support the documentation of various Ruby DSL’s through plugins. The code is not as elegant as it could be, but there is a general framework in place that can be whipped up into something much more usable. Once this is done, YARD can start talking to framework developers to write YARD plugins and use Yardoc formatting. Merb would be a great place to start since they’re already going in that direction.

0.4.0 – 0.4.9: Revamping the templates

Currently YARD was prototyped with a basic Javadoc-style template just to show off some of the inheritance features it has over RDoc doc templates. It’s not meant to be pretty right now. That needs to change eventually, but should be easy once the API is tacked down. YARD can potentially provide a number of templates for different peoples’ tastes, from Javadoc (for JRuby guys) to a more Ruby feel, and everything in between. Output will not be limited to XHTML of course, and can be done in plaintext, man files, etc.

0.5.0 – 0.5.9: Bring it to the community / design review & feature requests

As much as I have my say in software I make, other people have their own. It’s important to hear them out. This will be a good time to get the name out and start getting users using the software and evangelizing the benefits of YARD / structured documentation. I’ll be able to see what people can and can’t live with from a high level, and make some changes before it’s too late. Documentation, tutorials, howtos and basic written word can be fleshed out at this point, to give people better ways to access YARD’s internals.

0.6.0 – 0.6.9: Extend on API with optimization focus on raw data storage, consider database adapters.

One of the other goals of YARD is to provide a raw format for all the information that YARD collects about your source code. This enables developers to perform analysis on documentation through auditing tools, or simply provide a way to serialize the documentation data to another format that may not directly be for human consumption: YAML, XML, etc. This would also mean providing a way for developers to pull the contents from the raw data file to a database, which could enable developers to write interactive documentation applications for their frameworks/code (what is currently attempting to do– but manually, or even RailsLodge). This could even mean allowing YARD to store data directly to a database of choice using various SQL adapters.

0.7.0 – 0.7.9: Make YARD work with everyone’s code, up to 2.0

By this point the parser should be far superior to the current 0.2.1 state. Now it should be parsing Ruby’s source tree, Rails, Merb, etc. without issues. At this point we can pre-emptively start adding compatibility for Ruby1.9.x since this will need changes to the parser. Better now than after Ruby1.9.x is finalized.

0.8.0 – 0.8.9: Integrate YARD with Gems/Ruby

Currently when you release a gem you can have it generate RDoc. We’re going to want to change that– well, not change, just allow Yardoc generation. This will require some cross-patching, and a little convincing the gems guys that YARD is awesome. It should be at this point. Also, we want to have YARD generating Yardoc files for Ruby’s source tree when it installs at this point so that you can yri String, for instance, or link to the String class from your applications documentation.

This is where we would need to start converting Ruby’s RDoc format to Yardoc in preparation for the 1.0. This will take a while and extend all the way through the 0.9.x run as well.

0.9.0 – 0.9.9: Run a round of stability patches and general bugfixes, feature-set should be stable.

Have another iteration of community feedback, last minute minor changes to the source for small fixes, minor feature additions/removals, but nothing too grand. YARD should already be awesome and integrated at this point, right? We should also be continuing to convert Ruby docs here.


Matz pulls YARD into Ruby as a standard module replacing RDoc. I can dream, right?

Help me dammit!

This project needs developers. Rewriting a parser isn’t easy, and that’s just one of the many steps involved. If anyone finds any shred of motivation to help in any way they can, pleasepleaseplease contact me [l s e g a l (a t) s o e n . c a]. I’m not usually the type to ask for help but it would be extremely healthy for this any project not to hinge on just one person. If there’s any set of features listed above that you think you can tackle and you actually want to see this get done, get in touch. Stuff like template design, coding, writing documentation, testing, or even just blogging about the project / making a screencast (when there’s something to screencast, of course), it all helps.

Questions? Comments? Follow me on Twitter (@lsegal) or email me.