Homepage: http://yard.rubyforge.org
IRC: Join us on IRC in #yard on irc.freenode.net!
Git: http://github.com/lsegal/yard
Author: Loren Segal
Copyright: 2007-2009
License: MIT License
YARD is a documentation generation tool for the Ruby programming language. It enables the user to generate consistent, usable documentation that can be exported to a number of formats very easily, and also supports extending for custom Ruby constructs such as custom class level definitions. Below is a summary of some of YARD's notable features.
1. RDoc/SimpleMarkup Formatting Compatibility: YARD is made to be compatible with RDoc formatting. In fact, YARD does no processing on RDoc documentation strings, and leaves this up to the output generation tool to decide how to render the documentation.
2. Yardoc Meta-tag Formatting Like Python, Java, Objective-C and other languages: YARD uses a '@tag' style definition syntax for meta tags alongside regular code documentation. These tags should be able to happily sit side by side RDoc formatted documentation, but provide a much more consistent and usable way to describe important information about objects, such as what parameters they take and what types they are expected to be, what type a method should return, what exceptions it can raise, if it is deprecated, etc.. It also allows information to be better (and more consistently) organized during the output generation phase. You can find a list of tags in the {file:GETTING_STARTED.markdown#taglist GETTING_STARTED.markdown} file.
YARD also supports an optional "types" declarations for certain tags. This allows the developer to document type signatures for ruby methods and parameters in a non intrusive but helpful and consistent manner. Instead of describing this data in the body of the description, a developer may formally declare the parameter or return type(s) in a single line. Consider the following Yardoc'd method:
##
# Reverses the contents of a String or IO object.
#
# @param [String, #read] contents the contents to reverse
# @return [String] the contents reversed lexically
def reverse(contents)
contents = contents.read if respond_to? :read
contents.reverse
end
With the above @param tag, we learn that the contents parameter can either be a String or any object that responds to the 'read' method, which is more powerful than the textual description, which says it should be an IO object. This also informs the developer that they should expect to receive a String object returned by the method, and although this may be obvious for a 'reverse' method, it becomes very useful when the method name may not be as descriptive.
3. Custom Constructs and Extensibility of YARD: Take for instance the example:
class A
class << self
def define_name(name, value)
class_eval "def #{name}; #{value.inspect} end"
end
end
# Documentation string for this name
define_name :publisher, "O'Reilly"
end
This custom declaration provides dynamically generated code that is hard for a
documentation tool to properly document without help from the developer. To
ease the pains of manually documenting the procedure, YARD can be extended by
the developer to handled the define_name
construct and add the required
method to the defined methods of the class with its documentation. This makes
documenting external API's, especially dynamic ones, a lot more consistent for
consumption by the users.
4. Raw Data Output: YARD also outputs documented objects as raw data (the dumped Namespace) which can be reloaded to do generation at a later date, or even auditing on code. This means that any developer can use the raw data to perform output generation for any custom format, such as YAML, for instance. While YARD plans to support XHTML style documentation output as well as command line (text based) and possibly XML, this may still be useful for those who would like to reap the benefits of YARD's processing in other forms, such as throwing all the documentation into a database. Another useful way of exploiting this raw data format would be to write tools that can auto generate test cases, for example, or show possible unhandled exceptions in code.
There are a couple of ways to use YARD. The first is via command-line, and the
second is the Rake task. There are also the yard-graph
and yri
binaries to
look at, if you want to poke around.
1. yardoc Command-line Tool
The most obvious way to run YARD is to run the yardoc
binary file that comes
with YARD. This will, among other things, generate the HTML documentation for
your project code. You can type yardoc --help
to see the options
that YARD provides, but the easiest way to generate docs for your code is to
simply type yardoc
in your project root. This will assume your files are
located in the lib/
directory. If they are located elsewhere, you can specify
paths and globs from the commandline via:
$ yardoc 'lib/**/*.rb' 'app/**/*.rb' ...etc...
The tool will generate a .yardoc
file which will store the cached database
of your source code and documentation. If you want to re-generate your docs
with another template you can simply use the --use-cache
(or -c)
option to speed up the generation process by skipping source parsing.
YARD will by default only document code in your public visibility. You can
document your protected and private code by adding --protected
or
--private
to the option switches.
You can also add extra informative files with the --files
switch,
for example:
$ yardoc --files FAQ,LICENSE
Note that the README file is specified with its own --readme
switch.
You can also add a .yardopts
file to your project directory which lists
the switches separated by whitespace (newlines or space) to pass to yardoc
whenever it is run.
2. Rake Task
The second most obvious is to generate docs via a Rake task. You can do this by
adding the following to your Rakefile
:
YARD::Rake::YardocTask.new do |t|
t.files = ['lib/**/*.rb', OTHER_PATHS] # optional
t.options = ['--any', '--extra', '--opts'] # optional
end
both the files
and options
settings are optional. files
will default to
lib/**/*.rb
and options
will represents any options you might want
to add. Again, a full list of options is available by typing yardoc --help
in a shell. You can also override the options at the Rake command-line with the
OPTS environment variable:
$ rake yardoc OPTS='--any --extra --opts'
3. yri
RI Implementation
The yri binary will use the cached .yardoc database to give you quick ri-style access to your documentation. It's way faster than ri but currently does not work with the stdlib or core Ruby libraries, only the active project. Example:
$ yri YARD::Handlers::Base#register
$ yri File::relative_path
4. yard-graph
Graphviz Generator
You can use yard-graph
to generate dot graphs of your code. This, of course,
requires Graphviz and the dot
binary. By default
this will generate a graph of the classes and modules in the best UML2 notation
that Graphviz can support, but without any methods listed. With the --full
option, methods and attributes will be listed. There is also a --dependencies
option to show mixin inclusions. You can output to stdout or a file, or pipe directly
to dot
. The same public, protected and private visibility rules apply to yard-graph.
More options can be seen by typing yard-graph --help
, but here is an example:
$ yard-graph --protected --full --dependencies
-
July.06.09: 0.2.3.2 release
-
Fix Textile hard-break issues
-
Add description for @see tag to use as link title in HTML docs.
-
Add --title CLI option to specify a title for HTML doc files.
-
Add custom.css file that can be overridden with various custom styelsheet declarations. To use this, simply add
default/fulldoc/html/custom.css
inside your code directory and use the-t
template directory yardoc CLI option to point to that template directory (the dir holding 'default'). -
Add support in
yardoc
CLI to specify extra files (formerly --files) by appending "- extra files here" after regular source files. Example:yardoc --private lib/**/*.rb - FAQ LICENSE
-
-
Jun.13.09: 0.2.3.1 release.
- Add a RubyGems 1.3.2+ plugin to generate YARD documentation instead of
RDoc. To take advantage of this plugin, set
has_rdoc = 'yard'
in your .gemspec file.
- Add a RubyGems 1.3.2+ plugin to generate YARD documentation instead of
RDoc. To take advantage of this plugin, set
-
Jun.07.09: 0.2.3 release. See the {file:WHATSNEW.markdown} file for a list of important new features.
-
Jun.16.08: 0.2.2 release. This is the largest changset since yard's conception and involves a complete overhaul of the parser and API to make it more robust and far easier to extend and use for the developer.
-
Feb.20.08: 0.2.1 release.
-
Feb.24.07: Released 0.1a experimental version for testing. The goal here is to get people testing YARD on their code because there are too many possible
code styles to fit into a sane amount of test cases. It also demonstrates the power of YARD and what to expect from the syntax (Yardoc style meta tags).
YARD © 2007-2009 by Loren Segal. Licensed under the MIT license. Please see the {file:LICENSE} for more information.