创建新的Rails项目并运行rails -v时出错

Question

I'm new to rails and I seem to get this error whenever I try to create a new project. Does anybody have any insight into what I need to do with this error message? I get the same error when running 'rails -v'

/Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/dependency.rb:298:in `to_specs': Could not find 'json' (~> 1.4) among 137 total gem(s) (Gem::LoadError)
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1271:in `block in activate_dependencies'
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1260:in `each'
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1260:in `activate_dependencies'
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1242:in `activate'
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1274:in `block in activate_dependencies'
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1260:in `each'
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1260:in `activate_dependencies'
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1242:in `activate'
from /Users/buckleyjosh/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/core_ext/kernel_gem.rb:48:in `gem'
from /Users/buckleyjosh/.rvm/gems/ruby-1.9.3-p194/bin/rails:18:in `<main>'
from /Users/buckleyjosh/.rvm/gems/ruby-1.9.3-p194/bin/ruby_noexec_wrapper:14:in `eval'
from /Users/buckleyjosh/.rvm/gems/ruby-1.9.3-p194/bin/ruby_noexec_wrapper:14:in `<main>'

Answer 1

The error is exactly what it's complaining about:

Could not find 'json' (~> 1.4) among 137 total gem(s)

Install that gem before you fire any rails commands : gem install json

If you're using rvm, make sure you've the right version of ruby loaded before installing the gem.
Read this more information on what this gem does.