How do you install Rails 4.0 in an RVM gemset?

Question

I am trying to install Rails into a new rvm gemset. I tried the following:

rvm gemset create rails-4.0 output: gemset created rails-4.0 

Next I did:

rvm [email protected] 

rvm gemset list:

gemsets for ruby-2.0.0-p0 (found in /Users/me/.rvm/gems/ruby-2.0.0-p0)    (default)    global => rails-4.0 

rails -v

Rails is not currently installed on this system. To get the latest version, simply type:

$ sudo gem install rails 

Do the rvm commands I listed not install rails 4.0?

Answer 1

This command:

rvm gemset create rails-4.0 

is creating basically a directory structure to hold the gems. You could have just as easily called it something other than "rails-4.0" like "foo" and it would be the same behavior.

This command:

rvm [email protected] 

Switches to Ruby 2.0.0 and tells it to use the new gemset named rails-4.0. Again, that could be "foo" or whatever you called it.

Now, to get Rails 4.0.x, you'd do:

gem install rails --version=4.0 

As Barrett pointed out earlier, to get a pre/beta/rc release, you can specify the whole version string, e.g. gem install rails --version=4.0.0.rc2.

Don't sudo, because you shouldn't sudo with rvm, even though it tells you to. With the "system ruby" (ruby not installed by rvm), it may be installed as root, so you need superuser (su) access (superuser do or "sudo") to do that. But, rvm has you install things as the current user, therefore you don't need to sudo.