Object-Oriented RI for IRB Console
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.


Object-oriented RI for IRB console


Finding documentation for Ruby gems and libraries is often time-consuming. ORI addresses this issue by bringing RI documentation right to your IRB console in a simple, consistent and truly object-oriented way.

If you're too lazy to read this README, watch this screencast instead.


Click here to skip the boring setup part and see live examples right away.

Pre-setup (test your environment)

  1. Check your Ruby version. Should be at least 1.8.7.

    $ ruby -v
    ruby 1.9.3p327 (2012-11-10 revision 37606) [i686-linux]
  2. Check your RI version. Should be at least version 2.5:

    $ ri --version
    ri 3.9.4
  3. Check if core RI documentation is available:

    $ ri Array.each

    You should see the doc article.

    If you see Nothing known about Array, you are missing the core RI documentation. To set it up, please follow the steps from README_RI_CORE.

Regular setup

Install the gem:

$ gem sources --add http://rubygems.org
$ gem install ori

Add to your ~/.irbrc:

require "rubygems"
require "ori"


$ irb
irb> Array.ri //
irb> Array.ri :each

RVM setup

Under Ruby Version Manager (RVM), install the gem into global gemset of Ruby versions you're using:

$ rvm 1.9.3
$ rvm gemset use global
$ gem install ori
$ gem install rdoc

Add to your ~/.irbrc:

require "rubygems"
require "ori"


$ irb
irb> Array.ri //
irb> Array.ri :each

Rails 3.x+Bundler setup

First, complete steps described in RVM setup.

Then, step into your Rails project directory:

$ cd myrailsproject

Add to your Gemfile:

group :development do
  gem "ori"
  gem "rdoc"


$ ri Array.each
$ bundle exec ri Array.each

You should see the doc article in both cases.

And finally:

$ rails console
>> Array.ri :each

Further important Bundler information

At the moment of this writing (2012-12-14) bundle install installs gems without RI documentation and it's not possible to change this behavior via options of any kind.

It means that you need to manually re-install the gems for which you need RI documentation. Example:

$ rails console
>> ActiveRecord::Base.ri :validate
No articles found

The above means that Rails components have been installed via bundle install and have no RI documentation. Let's fix it:

$ grep rails Gemfile
gem "rails", "3.2.8"
$ gem install rails -v 3.2.8

Rails gems are now re-installed, let's try again:

$ rails console
>> ActiveRecord::Base.ri :validate

(from gem activemodel-3.2.8)
  validate(*args, &block)


Adds a validation method or block to the class. This is useful when overriding
the validate instance method becomes too unwieldy and you're looking
for more descriptive declaration of your validations.

Seems to work now.

Local project doc setup

With a small hack it is possible to generate your own local project's RI documentation and make it instantly available in your IRB/Rails console.

To do it, add to your ~/.irbrc:

# Local doc hack.
if true
  path = "doc/ri"

  eval %{
    module Kernel

      def localdoc
        system("rdoc --ri --all -O -o #{path}")

    # Add local lookup path if it exists. Otherwise `ri` will refuse to find anything at all.
    if File.directory? "#{path}"
      ORI.conf.frontend.gsub!("%s", "-d #{path} %s")
  } # eval

  puts "Local doc hack available. Use `localdoc` to update project's RI doc"
end # if true

Now in your project's IRB or Rails console you can do a:

>> localdoc

After the doc has been rebuilt, do a:

>> MyKlass.ri
>> MyKlass.ri :some_method

, and enjoy an up-to-date doc.

My own experience shows that the habit of using localdoc has at least two good consequences:

  • Now there is an incentive to document methods now, not "when time permits".
  • We can keep an eye on RDoc issues which occur during the doc generation. RDoc's parser is far from being perfect, but in many cases we can fix or work around certain quirks. It's much easier to do it in small portions as we go, rather than all at once.

If your experience is different from mine, feel free to share it!


All commands listed below are assumed to be typed in IRB. Example:

$ irb
irb> Array.ri

Request RI on a class

It's fairly straightforward -- grab a class or class instance and call ri on it:

ar = Array.new

Request RI on a method

String.ri :upcase
"".ri :upcase
[].ri :each
Hash.ri :[]
Hash.ri "::[]"
Hash.ri "#[]"

Request interactive method list

Interactive method list lets you explore the particular class or object by listing the methods it actually has. This powerful feature is my personal favorite. Try it once and you'll like it, too.

# Regular expression argument denotes list request.
String.ri //
"".ri //

# Show method names matching a regular expression.
"".ri /case/
"".ri /^to_/
[].ri /sort/
{}.ri /each/

# Show own methods only.
Time.ri //, :own => true
Time.ri //, :own

# Show ALL methods, including those private of Kernel.
Hash.ri //, :all => true
Hash.ri //, :all

# Show class methods or instance methods only.
Module.ri //, :access => "::"
Module.ri //, :access => "#"

# Specify visibility: public, protected or private.
Module.ri //, :visibility => :private
Module.ri //, :visibility => [:public, :protected]

# Filter fully formatted name by given regexp.
Module.ri //, :fullre => /\(Object\)::/

# Combine options.
Module.ri //, :fullre => /\(Object\)::/, :access => "::", :visibility => :private

Request interactive method list for more than 1 object at once

By using the :join option it's possible to fetch methods for more than 1 object at once. Value of :join (which can be an object or an array) is joined with the original receiver, and then a combined set is queried.

# List all division-related methods from numeric classes.
Fixnum.ri /div/, :join => [Float, Rational]
5.ri /div/, :join => [5.0, 5.to_r]

# List all ActiveSupport extensions to numeric classes.
5.ri //, :join => [5.0, 5.to_r], :fullre => /ActiveSupport/

# Query entire Rails family for methods having the word "javascript".
rails_modules = ObjectSpace.each_object(Module).select {|mod| mod.to_s.match /Active|Action/}
"".ri /javascript/, :join => rails_modules


You can configure ORI via ORI.conf object. By default it's autoconfigured based on your OS and environment.

# Enable color.
ORI.conf.color = true

# RI frontend command to use. `%s` is replaced with sought topic.
ORI.conf.frontend = "ri -T -f ansi %s"

# Paging program to use.
ORI.conf.pager = "less -R"


Tested to run on:

  • Ruby 1.9.3-p0, Linux, RVM
  • Ruby 1.9.2-p290, Linux, RVM
  • Ruby 1.9.2-p0, Linux, RVM
  • Ruby 1.8.7-p352, Linux, RVM
  • Ruby 1.8.7-p302, Linux, RVM
  • Ruby 1.8.7-p72, Windows, Cygwin
  • Ruby 1.8.7-p72, Windows

Compatibility issue reports will be greatly appreciated.


Copyright © 2011-2012 Alex Fortuna.

Licensed under the MIT License.


Send bug reports, suggestions and criticisms through project's page on GitHub.