在使用'sudo gem update --system'更新我的ruby设置后尝试启动rails控制台时，我尝试通过发出rails c
我收到此错误：
Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/dependency.rb:247:in `to_specs': Could not find json (~> 1.4) amongst [Ascii85-1.0.1, abstract-1.0.0, actionmailer-3.1.1, actionmailer-3.1.0, actionmailer-3.0.9, actionmailer-3.0.5, actionmailer-3.0.3, actionpack-3.1.1, actionpack-3.1.0, actionpack-3.0.9, actionpack-3.0.5, actionpack-3.0.3, activemodel-3.1.1, activemodel-3.1.0, activemodel-3.0.10, activemodel-3.0.9, activemodel-3.0.5, activemodel-3.0.3, activerecord-3.1.1, activerecord-3.1.0, activerecord-3.0.9, activerecord-3.0.5, activerecord-3.0.3, activeresource-3.1.1, activeresource-3.1.0, activeresource-3.0.9, activeresource-3.0.5, activeresource-3.0.3, activesupport-3.1.1, activesupport-3.1.0, activesupport-3.0.10, activesupport-3.0.9, activesupport-3.0.5, activesupport-3.0.3, addressable-2.2.6, ansi-1.3.0, arel-2.2.1, arel-2.0.10, arel-2.0.9, arel-2.0.7, bcrypt-ruby-3.0.1, bcrypt-ruby-3.0.0, bcrypt-ruby-2.1.4, builder-3.0.0, builder-2.1.2, bundler-1.0.21, bundler-1.0.18, bundler-1.0.11, choices-0.2.4, cocaine-0.2.0, coffee-rails-3.1.1, coffee-rails-3.1.0, coffee-script-2.2.0, coffee-script-source-1.1.2, devise-1.4.8, devise-1.4.2, erubis-2.7.0, erubis-2.6.6, execjs-1.2.9, execjs-1.2.6, execjs-1.2.4, faraday-0.7.4, faraday-0.6.1, faraday_middleware-0.7.0, faraday_middleware-0.6.3, fastercsv-1.5.4, formtastic-2.0.2, formtastic-1.2.4, geocoder-1.0.4, geocoder-1.0.2, has_scope-0.5.1, hashie-1.1.0, hashie-1.0.0, heroku-2.7.0, hike-1.2.1, i18n-0.6.0, i18n-0.5.0, inherited_resources-1.3.0, inherited_resources-1.2.2, jquery-rails-1.0.16, jquery-rails-1.0.14, kaminari-0.12.4, launchy-2.0.5, libv8-3.3.10.2-x86_64-darwin-10, mail-2.3.0, mail-2.2.19, mail-2.2.15, mail-2.2.14, mechanize-2.0.1, mechanize-1.0.0, meta_search-1.1.1, meta_search-1.0.6, mime-types-1.16, multi_json-1.0.3, multi_xml-0.4.1, multi_xml-0.4.0, multi_xml-0.3.0, multi_xml-0.2.2, multipart-post-1.1.3, multipart-post-1.1.2, mysql-2.8.1, mysql2-0.3.7, mysql2-0.2.7, mysql2-0.2.6, net-http-digest_auth-1.1.1, net-http-persistent-2.1, net-http-persistent-2.0, net-http-persistent-1.9, nokogiri-1.5.0, nokogiri-1.4.4, orm_adapter-0.0.5, pdf-reader-0.10.0, pg-0.11.0, polyamorous-0.5.0, polyglot-0.3.2, polyglot-0.3.1, prawn-0.12.0, rack-1.3.4, rack-1.3.3, rack-1.3.2, rack-1.2.3, rack-1.2.2, rack-1.2.1, rack-cache-1.1, rack-cache-1.0.3, rack-mount-0.8.3, rack-mount-0.6.14, rack-mount-0.6.13, rack-ssl-1.3.2, rack-test-0.6.1, rack-test-0.5.7, rails-3.1.1, rails-3.1.0, rails-3.0.9, rails-3.0.5, rails-3.0.3, railties-3.1.1, railties-3.1.0, railties-3.0.9, railties-3.0.5, railties-3.0.3, rake-0.9.2, rake-0.8.7, rake-0.8.7, rash-0.3.1, rash-0.3.0, rdoc-3.10, rdoc-3.9.4, rdoc-3.9.2, responders-0.6.4, rest-client-1.6.7, rubygems-update-1.8.11, rubygems-update-1.8.10, rubygems-update-1.7.2, rubygems-update-1.7.1, rubygems-update-1.6.2, rubyzip-0.9.4, sass-3.1.10, sass-3.1.7, sass-rails-3.1.4, sass-rails-3.1.2, sass-rails-3.1.0, simple_oauth-0.1.5, sprockets-2.0.2, sprockets-2.0.0, sqlite3-1.3.4, term-ansicolor-1.0.6, therubyracer-0.9.4, thor-0.14.6, tilt-1.3.3, treetop-1.4.10, treetop-1.4.9, ttfunk-1.0.3, ttfunk-1.0.2, turn-0.8.2, twitter-1.7.1, twitter-1.4.1, tzinfo-0.3.30, tzinfo-0.3.29, tzinfo-0.3.26, tzinfo-0.3.24, uglifier-1.0.3, warden-1.0.6, warden-1.0.5, webrobots-0.0.12, webrobots-0.0.11] (Gem::LoadError)
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1932:in `block in traverse'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1931:in `each'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:1931:in `traverse'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:465:in `block in find_in_unresolved_tree'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:463:in `reverse_each'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/specification.rb:463:in `find_in_unresolved_tree'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:47:in `require'
from /Users/myusername/.rvm/gems/ruby-1.9.2-p136/gems/railties-3.1.1/lib/rails/script_rails_loader.rb:1:in `<top (required)>'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:55:in `require'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:55:in `require'
from /Users/myusername/.rvm/gems/ruby-1.9.2-p136/gems/railties-3.1.1/lib/rails/cli.rb:2:in `<top (required)>'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:55:in `require'
from /Users/myusername/.rvm/rubies/ruby-1.9.2-p136/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:55:in `require'
from /Users/myusername/.rvm/gems/ruby-1.9.2-p136/gems/rails-3.1.1/bin/rails:7:in `<top (required)>'
from /Users/myusername/.rvm/gems/ruby-1.9.2-p136/bin/rails:19:in `load'
from /Users/myusername/.rvm/gems/ruby-1.9.2-p136/bin/rails:19:in `<main>'
有什么想法吗？
答案 0 :(得分：7)
当你尝试列出你的宝石时你会得到什么...是json＆gt; = 1.4那里？
e.g：
> gem list json
*** LOCAL GEMS ***
json (1.6.1, 1.5.4, 1.5.3, 1.5.1, 1.4.2)
json_pure (1.6.1, 1.5.4, 1.5.3)
如果您使用RVM gemsets，您可能还想列出它们，以检查您的默认gemset是否已更改：
rvm gemset list
编辑：解决了谜题！： - ）
您意外地使用sudo安装了宝石 - 但您已为自己的用户帐户安装了RVM！
如果你为一个用户安装了RVM，那么做一个sudo gem install ...通常不是一个好主意，但你应该只为本地用户安装gems并让RVM管理它们，无论你是什么Ruby版本使用
如果您仍然使用sudo进行安装，RVM将无法找到这些宝石，因为它们存储在RVM之外的其他位置，而不是由RVM搜索...！看起来就像你经历的那样。
检查此RailsCast：http://railscasts.com/episodes/200-rails-3-beta-and-rvm
如果您使用的是Rails：
- 编辑您的Gemfile 并添加json依赖项，然后运行bundle install
如果您只是单独使用Ruby，或者是旧版本或Ruby：
- 在shell中运行gem install json
对于较新的Ruby版本，您不应手动安装gem
答案 1 :(得分：2)
在Gemfile中添加gem "json", "~> 1.4"并运行bundle install
答案 2 :(得分：2)
另外
您仅在安装过程中使用sudo命令。在多用户配置中，任何需要sudo访问的操作都必须使用rvmsudo命令来保留RVM环境并将其传递给sudo。除了更新RVM本身之外，核心安装完成后需要rvmsudo的情况非常少。永远没有理由在安装后使用sudo。一旦添加到'rvm'组的用户已经注销，然后返回以获得rvm组成员资格，只需要rvmsudo来更新RVM本身
rvmsudo rvm get head
请阅读https://rvm.beginrescueend.com/support/troubleshooting/页面安装程序页面还会为新安装详细说明。您需要删除现有安装并重做它才能正确重新配置权限。将来，从不用户 sudo 进行RVM安装时，除了安装时。 任何其他命令都不需要使用除
之外的rvmsudo rvm get head
更新您的安装。如果用户按照网站上的详细说明正确放置在rvm组中，则根本不需要使用sudo，只需要使用rvmsudo 进行更新。
此外，RVM不管理系统安装的ruby （）！我们确实提供
的使用rvm use system
为了提供一种在RVM控制的红宝石和系统之间切换的自然方式。您的软件包管理器或OS X缺少，负责管理系统安装的ruby，并且不受RVM 100％的控制。