How can I remove Ruby, Rails & mysql to start the installation process again?

I've been trying to get setup with Ruby on Rails today, but I think I've followed some bad instructions along the way, and nothing seems to work. I've now borrowed the book "Agile Web Development with Rails, Third Edition" from a friend, and want to follow the setup instructions in that. Firstly, do I need to remove what I've setup previously? If yes, how开发者_高级运维 do I do it? I can't seem to find instructions anywhere. I'm running OSX 10.6.1, so I know that it came with some stuff already setup, but I've been installing customized stuff over the top which I think I'll have to remove. Thanks for reading!

To uninstall gem you can use command line :

gem uninstall rails

You can list all of your gem with gem list and delete it all.

With MacOS, I recommend using rvm (http://rvm.beginrescue.com). It's a really great tool. To isolate yours rubies and yours gems. If you install rvm and want delete all your stuff, just rm -rf ~/.rvm is needed.

In your Home directory by default all gem are in directory ~/.gem/