Virb is an interactive Vim mode for IRB, Rails console, and Pry.

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IRB is Ruby's interactive REPL. IRB is a very handy tool, but its text-editing capabilities are limited. Virb wraps an IRB session in a Vim session and gives you convenient ways to evaluate Ruby code from Vim.

Virb inverts the approach taken by the interactive_editor gem and similar solutions which let you pop out into Vim from IRB and come back to IRB to see the results. Virb keeps you in Vim at all times, calling IRB behind the scenes and fetching IRB's output to display inside Vim.


gem install virb

Virb requires Ruby 1.9 and Vim 7.2 or above. Virb has been tested only on OS X 10.8 and Ubuntu Linux.

Using Virb

Start up Virb with the command

virb [file]

The optional file is a text file that contains Ruby code that you would like to run interactively.

Virb opens 2 Vim buffers. The bottom buffer is the interactive buffer, where you can edit Ruby code and then send it to the underlying interactive Ruby session for evaluation. The top buffer is the output buffer, where you can see the IRB session you are controlling from the interactive buffer.

To evaluate code in the interactive buffer:

To evaluate a line of code, put the cursor on it, and press ENTER in normal mode.

To evaluate several lines of code, you can either

  1. select the lines in Vim's visual mode, and press ENTER to evaluate them;
  2. use an ed-style range command: :[range]Virb

To clear the evaluation output butter, press CTRL-l.

If IRB takes too long (more than about half a second) to evaluate your code, you may need to manually force the session buffer to update itself. You can force an update by pressing SPACE in normal mode.

After you start up Virb, you can also monitor the IRB session you are driving by tailing a file called .virb/session (relative to the working directory).

Using Virb with Pry

Make sure you have the pry gem installed. Then you can run this:

virb-pry [file]

When virb opens, you should be able to send your code for evaluation to Pry and get Pry output in the virb session buffer.

How to wrap Rails console with Virb

If you want to use Virb with the standard Rails console:

Put this in your Gemfile:

group :development do
  gem 'virb'

and start Rails console as you do normally, with rails c. You should see the Virb interface open, where you can interact with the Ralis console through a Vim buffer and see its output in the other Vim buffer.

If you want to open a worksheet in Virb + Rails console, don't specify it on the command line. Open it from within Vim using :e [file] after the Virb session has started.

If you want to use Virb with Pry and Rails console:

Put this in your Gemfile:

group :development do
  gem 'pry'
  gem 'virb'

and start Rails console like this:

VIRB=pry rails c


The normal command line options for irb and pry do not work with virb.

Also, irb extensions and .irbrc settings that introduce output coloring may garble the evaluated output in Virb. For best results, remove these extensions.


Please report issues on the GitHub issue tracker.


You may want try adding a Vim plugin called ri.vim to perform Ruby documentation lookups from the Vim workspace. Virb and ri.vim are compatible, and written by the same author.


Virb was written by Daniel Choi, an independent software developer based in Cambridge, Massachusetts.