How to Install the Ruby Ri Documentation

How do I install the Ruby ri documentation?

Seems you have installer Ruby 1.9.1 distributed by the RubyInstaller project.

You can use the Windows Help Files (CHM) that came with the installer instead of the ri documentation.

The problem of the RI documentation is that some versions of RDoc have problems generating it and also generated more than 10 thousands files which slowed down the installers considerably.

How do I install ri documentation in JRuby?

I found out: it seems that the JRuby version of io/console does not work well with the Windows Command prompt: https://github.com/jruby/jruby/blob/master/lib/ruby/stdlib/io/console/jruby.rb.

A solution is, for example, to issue the rdoc --all --ri command within a Windows Git Bash rather than a Command prompt.

Ruby gem failure on installing ri documentation

Not a fix, really, but a workaround: Put this line:

gem: --no-rdoc --no-ri

into a file named ~/.gemrc to skip installation of rdoc and ri documentation (which you may not want on your system anyway - it will speed up the install process quite a bit).

Terminal stuck on installing ri documentation for rails

This has happened to me a few times. I believe it is a known issue which has never been resolved properly.

Simply install the gem without the documentation, if you don't mind, like the other answer suggests.

gem install rails --no-ri --no-rdoc

UPDATE (2020-04-29)

The new way of generating no documentation is adding the --no-document (in short -N) option, like so:

gem install rails --no-document # or -N in short

How to get the Ruby documentation from the command line

If you're using RVM to manage your Ruby installations you can do this:

rvm docs generate

If not, try doing this:

gem install rdoc-data
rdoc-data --install

then try the ri command again.

How do I generate ri documentation for custom objects and methods?

If you run rdoc from the directory containing your code, it can generate both ri and rdoc documents.

See the output of rdoc --help, or read through the RDoc site to learn more about the options, but in general you want the --ri-site flag.