How to install Anvil on Ubuntu 8.04 Hardy Heron

I just found an interesting Ruby programming framework Anvil. It makes Ruby MVC programming more efficient. Anvil is based on wxruby and works on multiple platforms.

These are the steps to install anvil:

1. install ruby by sudo aptitude ruby-full rubygems
2. update the gem by sudo gem update --system
3. sudo gem install anvil --include-dependencies

And then you may go to Anvil website and follow it to build your first Anvil application.

How to fix /usr/bin/gem:23: uninitialized constant Gem::GemRunner (NameError)

After I ran sudo gem update --system on Ubuntu 8.04 Hardy Heron, gem returns

/usr/bin/gem:23: uninitialized constant Gem::GemRunner (NameError)

when I run it.

The fix is very easy: Just add one line require 'rubygems/gem_runner' to /usr/bin/gem.